Monday, April 28, 2014

Holistic philosophy of personal wellness

Wellness is a choice of lifestyle marked by a balance of mind, body and spirit. It is a complex interaction that leads to quality of life. The term ‘quality of life’ (QoL) refers to the satisfaction of people with their lives, their physical, mental, social and emotional health and the nature of the environment in which they are living. Wellness is multidimensional and a holistic approach to personal health. Wellness is lifelong process of balancing physical, mental and social wellbeing and their interaction with the environment. Health literacy is important for a person to manage his health and prevent disease. Health literacy is defined as the degree to which individuals have the capacity to obtain, process and understand basic health information and services needed to make appropriate health decisions (U.S Department of Health and Human Services, USDHHS 2010). The World Health Organization (WHO 1947, 2009) introduced a holistic definition of health as “a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity.” Our health and well –being are the outcomes of the constant interaction between the several natural dimensions of life and wellness. Wellness is a holistic approach by which one can achieve and maintain optimal health. Wellness is a full integration of physical, mental and spiritual well-being. The term fitness is sometimes used interchangeably with health or wellness. The scope of fitness includes health-related, skill-related and physiological components (USDHHS, 2000).


According to the National Wellness Institute (2007), “wellness is an active process through which people become aware of, and make choices toward, more successful existence.”
According to Dunn (1959), “wellness is a state of health which comprises an overall sense of wellbeing and sees a person as consisting body, mind and spirit.”
Renger and co-authors (2000) defined wellness as consisting of physical, emotional, social, intellectual, and spiritual dimensions, and added environmental wellness to recognize the important impact of one’s surroundings.
Myers and Sweeney (2005) defined wellness as a way of life aimed at optimal health and well-being in which an individual integrates body, mind and spirit so as to live more fully within the human and natural context. Ideally, it is an optimal state of health and well-being that each individual is capable of achieving in all domains of his or her life (Myers, Sweeney and Witmer, 2001).
Adams (2003) has defined four main principles of wellness: 1) wellness is multi-dimensional; 2) wellness research and practice should be oriented toward identifying causes of wellness rather than causes of illness; 3) wellness is about balance; and 4) wellness is relative, subjective, and perceptual.

Wellness dimensions

Wellness is commonly viewed as having 7 dimensions or essential life areas such as physical, emotional, intellectual, social, spiritual, environmental and occupational.

Physical wellness –refers to wellness of the physical body. It is considered as an integral part of everyday wellness. Physical wellness encourages regular physical activities, proper nutrition and health care such as exercise or sports and personal hygiene. This type of physical activity discourages dependence on tobacco, alcohol and other drugs. Good nutrition is important for a health body and mind. Science has clearly determined that a lack of physical activity is detrimental to health. Physical wellness encompasses maintenance of cardiovascular fitness, flexibility and strength. A regular weekly programme of walking, jogging, cycling, aerobics, swimming, strength training and stretching exercises helps improve or maintain physical fitness.

Emotional wellness – reflects our ability to appropriately control and express our emotions. Emotional wellness helps us to cope and comfortable with our emotions. Emotional wellness implies the ability to express emotions appropriately, adjust to change, cope with stress in a healthy way, and enjoy life despite its occasional disappointments and frustrations. Emotional wellness involves attending to our own thoughts and feelings, monitoring our reactions and identifying obstacles to emotional stability. Emotional awareness and acceptance help diminish the emotional intensity of the situation and increase one’s ability to handle a situation productively.

Intellectual wellness – is the utilization of human resources and learning resources to expand knowledge and improve skills. It refers to one’s ability to analyse, synthesize and act on new information. Intellectual wellness refers to active participation in scholastic, cultural and community activities. Intellectual wellness represents a commitment to lifelong learning, an effort to share knowledge with others and development of skills and abilities to achieve a more satisfying life.

Social/ interpersonal wellness – involves interacting with people and the environment and having satisfying relationships. The social environment is created by the interaction of people and their relationships with one another.  It involves developing friendships, healthy sexual behaviours, the ability to interact comfortably with others generally works for harmony in personal and community environments. Social wellness means you have friends with whom you discuss your problems and with whom you spend time. Social wellness involves not only a concern for the individual, but an interest in humanity as a whole.

Environmental/aesthetic wellness – Environment is an essential dimension of wellness. Research shows that our health and well-being are influenced by everything around us, whether in the built or natural world. Safe air, land and water are fundamental to a healthy community environment. The environment can have a significant impact on levels of physical activity, and on physical and emotional health and well-being.

Spiritual wellness – is to possess a set of guiding beliefs, principles or values that give meaning and purpose to one’s life.  Spiritual wellness means working to achieve spiritual potential and find harmony in living. The spiritually well person focuses on the positive aspects of life and finding solutions to negative feelings from the organized religions. Many people find meaning and purpose in their lives on their own through nature, art, meditation or community service.

Occupational/ vocational wellness –involves creating a healthy and supportive work environment which recognizes personal satisfaction and enrichment in one’s life through work. It's better to develop functional, transferable skills through structured involvement opportunities than to remain inactive and uninvolved.  It's better to choose a career which is consistent with our personal values interests and beliefs than to select one that is unrewarding to us.

Life style diseases and global wellness

Chronic diseases are the leading causes of death throughout the world.  Globally, of the 58 million deaths in 2005, approximately 35 million was as a result of chronic diseases. Deaths from chronic diseases are expected to increase by 17% over the next 10 years from 35 million to 41 million. Only 20% of chronic disease deaths occur in high income countries- while 80% occur in low and middle income countries, where most of the world population lives (WHO 2005).  Chronic diseases are responsible for seven out of every 10 deaths in the United States, killing more than 1.7 million Americans every year. Reports from the United States estimate that the population – attributable risk of physical inactivity is responsible for 12 % of type 2 diabetes and 22% of coronary heart disease as well as significant shares of other poor health conditions.   The estimate on Indian population in 2005 reported that chronic diseases accounted for almost 53% of all deaths and 44% of disability – adjusted life years (DALYs).In economically developed countries such as Japan, the United States, Australia and most of Europe, nearly 50% of the chronic disease burden is associated with 5 risk factors: tobacco use, high blood pressure, alcohol use, high cholesterol and overweight. But in the developing countries, deaths from chronic disease result from different risk factors: underweight, unsafe sex (causing HIV/AIDS), unsafe water and sanitation and indoor smoke from pollution.  Many chronic diseases could be prevented, frequently manageable through simple lifestyle changes.  The chronic disease threat can be easily overcome by using the existing scientific knowledge.

Effective wellness strategy

Stress management - Prolonged stress has an undeniable adverse effect on health. It can — and does — lead to illness. The ability to reduce and/or counter stress is critical in dealing with behavioural health problems, as well in promoting health and wellness. Yoga, meditation and deep breathing help reduce stress levels. It is advised to avoid over use of alcohol, caffeine, energy drinks, high sugar foods and stimulant drugs.  It is said by an unknown author that “The best cure for the body is to quiet the mind.”

Physical activity- Exercise and other forms of physical activity not only help maintain a healthy weight, but also help improve overall health and behavioural health — and reduce stress. John F.Kennedy said, “Physical fitness is not only one of the most important keys to a healthy body, it is the basis of dynamic and creative intellectual activity.”

Healthy nutrition- The quality and the balance of food in our diet has enormous impact on our health. Developing personal eating habits that promote better health is important for everyone, especially people who have health problems like diabetes, heart disease, and high blood pressure. During some chronic illnesses, eating healthy becomes vital to prevention and recovery.John Lubbock said, “Health is much more dependent on our habits and nutrition than on medicine.”

Restful sleep- The human body needs at least 8 hours of sleep each day to function at optimal levels, to repair and recharge. Long-term sleep deprivation is associated with many illnesses, including high blood pressure, heart attack, stroke, obesity, and behavioural health problems. Thomas Dekker said, “Sleep is that golden chain that ties health and our bodies together.”

Community network and service - “Service to others” and “support network” are two sides of the same coin. We all need connectedness to survive. Service to others and support networks play a major role in initiating and sustaining personal wellness. Pearl S. Buck said, “To serve is beautiful, but only if it is done with joy and a whole heart and a free mind.”

Positive mental attitude- Personal hope that one’s life can be better encourages happiness and a sense of wellbeing. In fact, research has found that heart patients with optimistic recovery expectations are 30% less likely to die over the next 15 years than less optimistic patients, regardless of disease severity. Peter Sampson said, “What really makes you healthy in life is your mental attitude. If it affects you in a positive way, it’s worth it.”

A sense of meaning and purpose- Many people develop a sense of meaning and purpose through spirituality, ultimately converging a person’s beliefs and values. Patricia Ryan Madson said, “A life of meaning and value is achieved through purposeful action.”


Wellness is an active, lifelong process of becoming aware of choices and making decisions toward a more balanced and fulfilling life. Wellness places responsibility on the individual; it becomes a matter of self-evaluation and self – assessment. Wellness involves continually learning and making changes to enhance one’s state of wellness. Wellness is understood as a total person’s approach towards improving the quality of one’s health.  It is acknowledged that wellness is characterised by optimal physical health as well as psychological and social well-being and not by the mere absence of illness.

Sunday, April 27, 2014

Maximizing the learning abilities

Learning is a process of storage of knowledge (knowledge construction process) in our memory.  “Learning is a process as well as an outcome” (Zuber-Skerritt1992). Learning is the process whereby knowledge is created through the transformation of experience ( Kolb 1984).Learning is the major process of human adaptation. Learning is ‘sense making’. All learners are meaning makers. Learning is the process that underlies and gives birth to change. Change is the child of learning (Friedlander,1983).  Learning is a cognitive process of acquiring new skills, knowledge and attitude. Learning is repeated experience, modulated by attention and weighted by emotional relevance. Different people learn information in different ways. There are 4 requirements of learning: motivation, time, preparation and method. All human beings are born with an astounding capacity to learn, both in amount that can be learned in one domain and in the variety and range of what can be learned. Learning is a multi-step process such as acquisition, retention and retrieval. Learning is an ongoing and never ending process. It begins at the moment of birth and continues through an entire lifespan. Learning is the act of interpreting experience and the interpretation is based on the individual’s process of sense making.
There are 3 stages in learning such as registering the item, filing the item and retrieving the item. The learning involves techniques, motives, attitudes and definitions.
 Learning depends upon priority, intensity and duration.
There are four elements that constitute successful learning.  
  1. Wanting – motivation
  2. Doing – practice, trial and error
  3. Feed back – seeing the results; other people’s reactions
  4. Digesting – making sense of it; gaining ownership.
According to holistic learning theory, an individual personality consists of many elements such as the intellect, emotions, the desire, intuition and imagination. All require activation, if learning is to be more effective.

Basic views about learning

Learning is a natural process. The natural tendency of the brain is to learn, however not everyone learns in the same way. Learning is a social process. Students learn best in collaboration with peers, teachers, parents and others. Learning is an active process. Learning is an activity in which learners participate and are directly involved. Learners must be actively engaged in learning process. Learning can be either linear or non-linear process. Learning is a reorganization of knowledge structures. Mind is a wonderful parallel or serial processor. Learning is integrative and context –based. Learners themselves see relations and make connections. Teachers can help learners to make connections and to integrate knowledge. Learning is based on a strength model of student abilities, interest and culture.  Learning causes a relatively permanent change in the behaviour –attitude, interest or value.  The change may be an improvement of a skill or process. It may be a modification where old knowledge, skills and abilities or attitudes are adjusted to cope with new circumstances.

Characteristics of learning

Pedler (1997) identified 4 different aspects of learning. Students can learn about things. Students acquire and understand the knowledge. Students can learn to do things. Students acquire new skills, abilities and competencies. Students can learn to achieve full potential in their lives. Students want personal development involving intellectual growth and skill acquisition. Students can learn to achieve things together which Pedler calls collaborative enquiry – to do things together.

Learning- based changes in the brain

Learning takes place in the brain in three major stages:
 Some of the brain's 100 billion nerve cells (neurons) sprout branching fibres (axons and dendrites). All learning enters through our senses/emotions. This is the first stage of learning. As these neural fibres grow, they construct electrically and chemically activated connections (synapses) with other neurons and communicate, neuron to neuron, at these synapses. The  brain patterns and constructs mental maps of information. The brain actively binds ideas together through neural networking. This second stage of learning is more productive. As this neural growth continues, ever-more neural pathways and synaptic connections are constructed until there is a complex network of connections between many neurons for that particular object of learning. This is complex, high-level and in-depth learning. According to Jeannett Vosss and Gordon Dryden in their book ‘the learning revolution’ stated that learning to store information in patterns and with strong associations is probably the first step in developing our brain’s untapped ability.

Kinds of learners

Researchers and educators categorised learners into three types like lookers, listeners and movers. The lookers are visual learners who rely on the sense of sight, when absorbing information. Text, diagrams, photograph, charts, graphs and maps are all tools that aid visual learning. The listeners are auditory learners with a preference for sounds and words over information taken in by either sight or touch. The movers are tactile (kinaesthetic) learners preferring hands-on learning through both touch and movement. It emphasizes the need to touch objects and move one’s body.

Principles of learning (Svinicki, 1991)

If information is to be learned, it must first be recognized as important. During learning, learners act on information in ways that make it more meaningful by using examples, images, elaborations and connections. Learner store information in long – term memory in an organized fashion related to their existing understanding of the world. Learners continually check understanding, which results in refinement and revision of what is retained. Transfer of learning to new contexts is not automatic but results from experience to multiple applications. Learning is facilitated, when learners are aware of their learning strategies and monitor their use.

Categories of learning

Formal learning – takes place in educational institutions.
Non – formal learning – takes place outside and through the activities of civil society, groups and organizations.
Informal learning – is a natural accompaniment to everyday life.
Lifelong learning – is learning throughout life either continuously or periodically.
Life wide learning – can take place across the full span of our lives at any one stage in our lives.
Social learning – can take place in a social setting or context. Social interaction allows learners to relate or mirror their ideas, insights, experiences and feelings to those of others.

Kinds of learning systems

Natural learning system- the brain has natural learning systems such as emotive, cognitive, physical, social, and reflective.
Cognitive learning system – cognition interprets, stores and retrieves information via pattern and pictures. It establishes integrated circuits of knowledge and skills.
Physical learning system – it gathers information through all senses. It distributes information throughout the brain and the body. It converts inputs into action.
Social learning system – it governs interactions and communications with others. Team work and team accomplishment are integral to integrated system.  People works together in pairs or small groups to solve problems.
Emotional learning system – involves personal meaning and its relevance. It accelerates learning.
It empowers or energises or depresses or stifles all other learning systems. It manages a learner’s motivation, demeanour and creativity.
Reflective learning system – it weighs past, present, and future projections. It interprets verbal and non-verbal cues.  It is a monitoring mechanism and it metacognates information.

Learning tools

Knowledge dissemination tools – are systematic attempts to identify and distribute knowledge and ideas.
Instructional tools – teaching methods used to share knowledge and ideas.
Research and development tools – are designed to generate new discoveries through organized inquiry.
Diagnostic tools are designed to evaluate the learning that takes place in a learner.
Learning how to learn (individual learning) – may be defined as the capacity to build knowledge on their own. Learning is an individual process. It takes place inside an individual’s brain.

Kolb’s Learning cycle

Kolb's four-stage model is a simple description of the learning cycle which shows how experience is translated through reflection into concepts, which in turn are used as guides for active experimentation and the choice of new experiences. Kolb refers to these four stages as: concrete experience (CE), reflective observation (RO), abstract conceptualization (AC) and active experimentation (AE).
1. Concrete experience (CE)–having a new experience of situation or reinterpretation of existing experience.
2. Reflective observation (RO) – reviewing/ reflecting on the experience.
3. Abstract conceptualization(AC) –formation of abstract concepts (analysis)by reflection and generalization (conclusion)
4. Active experimentation (AE) – planning and trying out what one have learned.

Kolb’s learning style

Diverging (feeling and watching - CE/RO) -The people with diverging abilities are able to look at things from different perspectives. They prefer to watch rather than do, tending to gather information and use imagination to solve problems. They have broad cultural interests and like to gather information. They are interested in people, tend to be imaginative and emotional, and tend to be strong in the arts. They prefer to work in groups, to listen with an open mind and to receive personal feedback.
Assimilating (watching and thinking - AC/RO)
People with an assimilating learning style are less focused on people and more interested in ideas and abstract concepts.  They are more attracted to logically sound theories rather than approaches based on practical value. These people are important for effectiveness in information and science careers. In formal learning situations, people with this style prefer readings, lectures, exploring analytical models, and having time to think things through.
Converging (doing and thinking - AC/AE)
People with a converging learning style can solve problems and they prefer technical tasks. They  are less concerned with people and interpersonal aspects. People with this learning style are best at finding practical uses for ideas and theories. They can solve problems and make decisions by finding solutions to questions and problems. People with a converging style like to experiment with new ideas, to simulate, and to work with practical applications.
Accommodating (doing and feeling - CE/AE)
The Accommodating learning style is 'hands-on', and relies on intuition rather than logic. These people use other people's analysis, and prefer to take a practical, experiential approach. They are attracted to new challenges and experiences, and to carrying out plans. This learning style is prevalent within the general population.

Effective learning tips from theories of learning

  1. Learning involves both focused attention and peripheral perception. People learn best when solving realistic problems. Learning involves search for meaning and patterning. Learning is influenced by emotions, feelings and attitudes (Brain-based learning).
  2. Learning is based on neuro-sensation (smell, sight, taste, hearing and touch) and occurs in stages, steps or levels and is most effectively stored, recalled and utilized. Learning is strengthened by rich sensory, emotive and kinaesthetic association (Neuro-biological learning theory).
  3. Learning new knowledge is dependent on what is already known. New knowledge gains meaning when it can be largely related to a framework of existing knowledge (Meaningful learning theory).
  4. Verbal learning is most effective when accompanied by visual learning (Dual coding theory).
  5. Learning can be achieved more as a direct participation and reflection of every day experience (Experiential learning).
  6. Learning is centred around the need to find a solution to real problem (Action learning)
  7. Learning occurs more when actively searching for information (Discovery learning).
  8. Optimum learning occurs when the load on the working memory is kept to a minimum to facilitate the changes in long term memory (Cognitive load theory).
  9. A learner is able to use prior knowledge and experience to interpret the content. New information is compared to existing cognitive structures called schema (Schema theory of learning). Learning is much easier if connections are made between ideas and facts.
  10. Learning can be maximised by learning of rule –based or information – based categories or exemplars or prototypes. (Category learning).
  11. Learners actively construct and reconstruct knowledge out of their experience in the world. Reflection and metacognition are essential aspects of constructing knowledge and meaning (Constructivist learning theory).
  12. If learning is to be effective, it should involve all aspects of an individual’s personality such as the intellect, emotions, the desire, intuition and imagination (Holistic learning theory).
"Our brain is best at learning what it needs to learn
  to survive, socially, economically, emotionally and physically."

"The capacity to learn is a gift;
  the ability to learn is a skill;
  the willingness to learn is a choice." -Brian Herbert.

Wednesday, April 23, 2014

Scientific modeling

A modeling is the most basic learning task of acquiring the ability to organize information about the world into a useful structure. A model is a systematic description of an object or phenomenon (event or process) that shares important characteristics with its real-world counterpart and supports its detailed investigation. A modeler may be a researcher, a inventor, a designer, a teacher or an artist. Models are commonly represented as a system of postulates, data, and inferences presented visually, in material form, in mathematical terms, or as a computer simulation. Scientific models invariably involve some degree of idealization, abstraction, or fictionalization of their target system e.g., the Bohr model of the atom, the Lorenz model of the atmosphere, and the Lotka-Volterra model of predator-prey interaction.  Models can perform two fundamentally different representational functions. A model can be a representation of a selected part of the world (the ‘target system’). Depending on the nature of the target, such models are either models of phenomena or models of data. On the other hand, a model can represent a theory in the sense that it interprets the laws and axioms of that theory.  Simply a scientific model is a representation of a system (e.g., the solar system) or a phenomenon (e.g., the oxidation of metal, or thermoregulation in humans). These representations can take the form of pictorials-drawings, diagrams, flow charts, equations, graphs, computer simulations, or even physical objects.

A model is a formal, abstract, hypothetical  description of a complex entity, system or process. Scientific models can be material, visual, mathematical or computational and are often used in the construction of scientific theories.  Models are representational system for observable and unobservable features of an entity or process. The term model is derived from Latin, modus/modulus meaning ‘little measure.’

Types of scientific models

There are two major types of models: Qualitative models often use verbal descriptions of general behavior. Quantitative models express units of analyses, their interrelations and dynamics using properties susceptible of measurement. Generally, 3 types of models used in science are physical models, mathematical models and conceptual models.
Physical or material model is a smaller or larger physical copy of an object e.g., Watson and Crick’s model of DNA, architectural model of a building, wooden models of bridges, planes or ships.
Mathematical model is a description of a system using mathematical concepts and languages. They are usually composed of relationships and variables. In other words, a mathematical model is one constructed using mathematical concepts such as constants, variables, functions, equations etc.
Conceptual or symbolic model is a descriptive model of a system that is based on qualitative assumptions about its elements, their relationships and system boundaries. It may be a set of concepts with propositions that describe them, express the relationships between them or set forth the basic assumptions of the model e.g., process flow models, data flow models, logical data model.

Other categories of models

Deductive models vs. inductive models
 Deductive models take a “top-down” approach by working from the more general to the more specific. Deduction can be seen as the identification of an unknown particular based on the resemblance of the particular to a set of known facts. Inductive models takes a "bottom up" approach that starts with specific observations and measures, continues with the identification of patterns and regularities, then formulates some tentative hypotheses that can be explored, and results in general conclusions or theories.
Deterministic models vs. stochastic models
Deterministic models describe the behavior of an object or phenomenon whose behavior is entirely determined by its initial state and inputs. e.g., Newton's laws can be used to describe and predict planetary motion. Stochastic or probabilistic models make it possible to predict the behavior of an object or phenomenon if the influence of several unknown factors is sizable—the subsequent state is determined both by predictable actions and by a random element.
Descriptive models vs. process models
Descriptive models aim to describe the major features of typically static data sets. Results are communicated via tables, charts, or maps. Process models aim to capture the mechanisms and temporal dynamics by which real-world networks are created. Computational models describe the structure of dynamics of science using different computational approaches such as agent based modeling, population models, cellular automata, or statistical mechanics.
Universal models vs. domain specific models
Universal models aim to simulate processes that hold true across different domains and data sets. Domain specific models aim to replicate a concrete data set in a given domain.
Iconic models (true models) – are large or small scale representation of states, objects or events. An iconic model is a truthful mirror image of the target except a transformation in scale e.g., road maps, pilot plant, aerial photograph.
Idealized model- is a deliberate simplification of something complicated with the objective of making it more tractable e.g., Philips curve in economics which specifies a relationship between inflation and unemployment.
Analogical models - is based on shared properties or relevant similarities between two things e.g., the hydraulic model of an economic system, the billiard ball model of a gas.
Phenomenological models - models that only represent observable properties of their targets and refrain from postulating hidden mechanisms and the like.

Steps in developing scientific models

Modeling is a process of selection and transformation. Selection firstly of what to represent that is to say defining the prototype and then of a set of characteristics of the prototype to be incorporated after appropriate transformation in the model.  It involves 4 steps:
Planning – this requires a clear definition of the problem.  The problem definition will establish a definite objective for analysis. This objective is invaluable in outlining a path from the problem to the solution. Are we interested in the process? What is our main concern? What is the appropriate response or dependent variable? What are the relevant explanatory or independent variables?
Data collection – this requires the Identification of response and explanatory variables. This is followed by predictions, extrapolations and interpolations of the problem.
Model fitting – different models which relate the response variable to the explanatory variables is tested to see how well they fit the experimental data.
Model validation – the model is evaluated using the experimental data not used in building the model.

Basic needs for modeling

One chooses to use a model under three situations.    

1. It is too complicated, expensive, dangerous or inconvenient to work with the prototype.
2. Complex situations are often difficult to grasp, difficult to describe and difficult to discuss.
3. There are situations in which a model may serve to generate variety.

Characteristics of good models

Keeping ideas simple – a good model use simple notations and represent the system with few rules and symbols.
Reliability – one can apply a model on a number of different occasions and the chosen model has to reliably reflect the behaviour of the system.
Validity – a model should reflect/ measure the dynamics of a system which it is supposed to reflect or measure.

Uses of models

Models are fundamental elements in learning about the world. Models give rise to a new style of reasoning, so-called ‘model based reasoning.’ Learning with models happens in three stages: denotation (representation of relation between the model and the target), demonstration (exhibiting certain theoretical claims about its internal constitution or mechanism), and interpretation/explanation (claims about the target system).
Models are used as partial substitutes for their prototypes to assist in designing, understanding, predicting the behavior, controlling or experiencing emotions associated the prototype.
A skilfully designed and constructed model can be a powerful means of communication.
Model is a tool to be used by the design team both to test the appropriateness of their plans and to assist in translating the final design into actuality. Often in the process of design, a series of models will be constructed each of which is intended to provide information on a particular aspect of the behavior of the prototype. Modelling is often the most appropriate research procedure.

Tuesday, April 22, 2014

Health benefits of plant alkaloids

Alkaloids are low molecular weight natural organic substances derived from plant sources. Alkaloids are defined as pharmacologically active nitrogen containing basic compounds of plant origin. The word alkaloid means alkali – like or vegetable alkali.  .  The term ‘alkaloid’ was coined by the German pharmacist Carl Friedrich Wilhelm Meissner in 1819 to refer to plant natural products.
 According to R.F. Raffauf (Plant Alkaloids: A Guide To Their Discovery and Distribution, 1996), more than 10,000 different alkaloids have been discovered in species from over 300 plant families.To date over 21,000 alkaloids have been identified.  About 20-30% plant species have been found to contain them. Many of the alkaloids are useful as drugs. The drugs may be either purified natural alkaloids or chemically modified alkaloids.  About 25% of the drugs used today are of plant origin. The plant alkaloids usually have a marked physiological action on man or other animals. The plants use alkaloids as defence chemical agents against herbivores and pathogens. Wink (1993) listed 183 alkaloids with antibacterial properties. The families Solanaceae and Apocynaceae are known for their alkaloid production, 60-70% of their members producing alkaloids. Alkaloid bearing species have been found in nearly all classes of organisms: frogs, ants, butterflies, bacteria, sponges, fungi, spiders, beetles and mammals. Some animals, such as frogs produce toxic alkaloids in the skin or secretary glands.

Ancient  phytotherapy

Alkaloids have been used throughout history in folk medicine in different regions of the world. The alkaloids from plant extracts have been used as ingredients in potions (liquid medicine) and poisons. Ancient people used plant extracts containing alkaloids for treating a large number of ailments including: snakebite, fever and insanity.  Humans have used alkaloids as poisons in weapons. From the times of Hippocrates (460 – 377 BCE), medicinal plants were used in Europe as herbal remedies for improving health. In ancient India and China, herbs were known and used even since 770 BCE. India has a very long, safe and continuous usage of many herbal drugs in the officially recognized alternative systems of medicine viz. Ayurveda, Yoga, Unani, Siddha, Homeopathy and Naturopathy. In India more than 70% of the population use herbal drugs for their health.Millions of Indians use herbal drugs regularly, as spices, home-remedies, health foods, as self-medication or also as drugs prescribed in the non-allopathic systems. The Indian medicinal plants are rich sources of beneficial compounds including antioxidants and components that can be used in functional foods.

Characteristics of alkaloids

The alkaloids are alkaline or basic in chemical reaction. They usually taste bitter. They have complex ring structures (usually with heterocyclic ring) and contain one or more nitrogen atoms. The dietary intake of small doses have  therapeutic effect as muscle relaxants, tranquillizers, pain killers, antimicrobials in human beings. Intake of large doses results in toxaemia or fatal. Many of the alkaloids are synthesized from amino acids such as tyrosine, tryptophan, ornithine, arginine and lysine.   

Physico-chemical properties

Alkaloids (as bases) are not soluble or sparingly soluble in water and soluble in apolar or only slightly polar organic solvents. They are soluble in concentrated hydro-alcoholic solutions. The alkaloids exist in plants in free states or as salts or as N-oxides. Elementally alkaloids consist of carbon, hydrogen and nitrogen. Most alkaloids also contain oxygen.  A few such as coniine from hemlock and nicotine from tobacco are oxygen-free. Most alkaloids have well defined crystalline structures which combine with acids to form salts. Most of the alkaloids have complex molecular structures with significant pharmacologic properties. An alkaloid never occurs alone; alkaloids are usually present as a mixture of a few major and several minor alkaloids of a particular biosynthetic unit, which differ in functional groups (Wink 2005).

Functions of alkaloids in plants

As poisonous agents, alkaloids protect the plants against insects and herbivores.  Alkaloids form as end products of detoxification reactions e.g., secondary metabolites. They serve as regulatory growth factors in plants. They also serve as reserve substances capable of supplying nitrogen or other elements necessary to the plant’s economy.

Biosynthetic origin of alkaloids

Alkaloids are mainly derived from amino acids. The amino acids that most often serve as alkaloidal precursors include phenylalanine, tyrosine, tryptophan, histidine, anthranilic acid, lysine and ornithine. Alkaloids also derived from other precursors like terepenes or steroids.

Naming of alkaloids

The name of all alkaloids ends with the suffix ‘–ine’. In addition the names of the alkaloids are based on various ways.
1.       From the generic name of the plant yielding them e.g., atropine from Atropa bellodona.
2.       From the specific name of the plant yielding them e.g., cocaine.
3.       From the common name of the drug yielding them e.g., ergotamine.
4.       From their physiologic activity e.g., emetine.
5.       From name of the discoverer e.g., pelletierine.

Classification of alkaloids

Typical or true alkaloids have heterocyclic ring with nitrogen derived from amino acids. They can be categorised into 14 groups according to their ring structures e.g., quinine, morphine, codeine etc.,
Atypical or protoalkaloids do not have heterocyclic ring with nitrogen derived from amino acids e.g., colchicines.
Pesudoalkaloids have heterocyclic ring with nitrogen not derived from amino acids. They can be derived from terpenoids or purines.
Chemical classification
Alkaloids are usually classified by their common molecular precursors based on the biological pathway used to construct the molecule.
1. Pyridine group – e.g., piperine, coniine, pilocarpine, nicotine.
2. Tropane group – e.g., atropine, cocaine.
3. Quinoline group – e.g., quinine, strychnine.
4. Isoquinoline group – e.g., opium alkaloids –morphine, codeine.
5. Phenylethylamine group – e.g., ephedrine, mescaline.
6. Indole group – e.g., reserpine, lysergic acid, emetine.
7. Purine group – e.g., caffeine.
8. Terpenoid group – e.g., aconitine.
9. Betaines – e.g., muscarine.

Health benefits

Alkaloids act on the central nervous system either as depressants (morphine) or stimulants (caffeine). They also act on the autonomic nervous system as sympathomimetics ( e.g., ephedrine), sympatholytics (e.g., yohimbine), parasympathomimetics (e.g., pilocarpine), anticholinergics (e.g., atropine) and ganglioplegics (e.g., nicotine). Alkaloids act as local anaesthetics (e.g., cocaine), agents to treat fibrillation (e.g., quinidine), anti-tumour agents (e.g., vinblastine), anti-malarials (e.g., quinine), antibacterials (e.g., berberine), amoebicides (e.g., emetine) and pain killer (e.g., codeine, morphine).

Monday, April 21, 2014

Nutritive value of vitamins

Vitamins are low molecular weight organic (carbon containing) compounds that are required in very small amounts for human growth, metabolism and health. Vitamins are essential nutrients. Vitamins cannot be bio-synthesized by the body but they must be ingested regularly through diet. The term “vitamine” was coined by Casimir Funk in 1912, meaning a basic essential for life. Generally vitamins and minerals are referred as vital body regulators because they are needed to make thousands of enzymes, hormones and other chemical messengers. Human beings need 13 vitamins and at least 10 minerals to stay healthy. Vitamins can be categorized into fat-soluble and water – soluble vitamins based on their solubility and polarity. Vitamins A, D, E and K (ADEK) are fat soluble and can be stored in fatty tissues and liver. The excess dietary intake could build up in the body and cause toxic effects. On the other hand vitamins B complex and C are soluble in water and harmless since there is little storage in the body.
Vital + Amines = Vitamin

Definition of vitamin

Vitamins are defined as “organic substances, needed in very small amounts that perform a specific metabolic function and must be provided in the diet of the animal.” They work as catalysts and substrates in metabolic reactions and some vitamins assist as co-factors for enzyme action.

Conditions of vitamin nutrition

Avitaminosis is a chronic or long-term vitamin deficiency e.g., night blindness(vitamin A),beri beri (vitamin B1), scurvy (vitamin C), rickets (vitamin D) and pellagra (vitamin B3).
Hypovitaminosis is caused by inadequate intake of one or more vitamins.
Hypervitaminosis results from excess intake of vitamins.
Antivitamins – a substance that destroys or inhibits the metabolic action of a vitamin e.g., avidin, sulphonamides.
Provitamins – a substance which the human body can convert into a vitamin e.g., beta carotene is a provitamin of vitamin A.  Dehydrocholesterol and ergosterol are provitamins of vitamin D.
Previtamins –a substance intermediate in the production of vitamins. A term synonym to provitamin.

Fat – soluble vitamins

Vitamin A
Vitamin A occurs in plants in the form of  provitamin carotene. The provitamin includes α -, β- and λ- carotenes and cryptoxanthin. The carotenes are the precursors of retinol. The modified forms of retinol are retinol (vitamin A aldehyde) and retinoic acid (vitamin A acid). Vitamin A is a 20-carbon compound with a β-ionone ring. The side chain is a highly unsaturated hydrocarbon unit. As many as 300 carotenoids have been identified in nature. The plant sources of β – carotenes include green leafy vegetables, carrot, red palm oil, and mango. The animal sources include fish liver oils (halibut, cod, and shark), milk, milk products and egg yolk. Avitaminosis results in the loss of night vision (nyctolopia). A failure of rod vision results in night blindness. The real sign of deficiency is xerophthalmia, dry keratinisation of cornea and conjunctiva. Vitamin A acts as an antioxidant (prevent cancer) as well as a hormone. It is essential for growth and differentiation of epithelial structure and bone. It promotes gluconeogenesis and synthesis of glycoproteins. The suggested daily dosage is about 700μg for adults and 300µg for children.
Vitamin D
Two forms of vitamin D are known. Cholecalciferol (D3) of animal origin is produced in the skin from a steroid previtamin7-dehydrocholesterol by sunlight (sunshine vitamin).  Calciferol (D2) is prepared synthetically by exposure of another provitamin ergosterol from yeast or plant sources. The two vitamins have the same activity in human beings. Ergosterol is obtained from plant sources like ergot and yeast. Dehydrocholesterol is obtained from animal sources like egg yolk, milk and fish liver oils. Vitamin D directly promotes the intestinal absorption of calcium and phosphorus. It facilitates calcification and development of bones. Vitamin D deficiency causes rickets in children and osteomalacia (a bone thinning disorder) and osteoporosis (reduced bone mineral density) in adults. The daily requirement of Vitamin D for children is estimated to be about 10μg (400 IU) and for adults is 5 µg (200 IU). The toxic symptoms of vitamin D Hypervitaminosis is loss of appetite, nausea, vomiting intense thirst and hypercalciuria (renal stone formation).
Vitamin E
Four forms of vitamin E are known such as α-, β-,λ- and ∆ - Tocopherol.  Chemically the compound is a 6- hydroxyl chroman with a phytyl side chain.  Vitamin E prevented sterility in human beings hence the name antisterility vitamin. The deficiency of vitamin E is shown to produce sterility, muscular dystrophy, haemolysis and megaloblastic anaemia. In infants vitamin E deficiency causes hemolytic anaemia.  Vitamin E is destroyed to great extent by cooking and food processing. The therapeutic daily dose is 500-1000 mg for the treatment of anaemia.  Dietary sources of vitamin E include leafy green and yellow vegetables, oils, grains, milk, meat and yeast. It plays an important role in maintaining stability and integrity of cell membranes. It has antioxidant properties and prevents free radical oxidation. It is relatively non-toxic.
Vitamin K
Vitamin E is a phytyl naphthoquinone occurring in the green leaves of most plants. There are two natural forms of this vitamin such as vitamin K1 (phylloquinone) and K2 (menaquinone). Vitamin K1 found in plants has a phytyl side chain and vitamin K2 produced by intestinal bacteria (microbial vitamin) has polyisoprenoid side chain. The dietary sources of vitamin K include green leafy vegetables, tomatoes, cauliflower, spinach, soybean oil, egg yolk and animal liver. Vitamin K is essential for normal blood clotting in wounds. Prothrombinogen and other blood clotting factors are formed in the liver with the help of vitamin K. The recommended daily allowance is 2 mg. The malabsorption of vitamin K results in the prolongation of clotting time and haemorrhages following an injury (hypoprothrombinemia).  Hypervitaminosis results in hyperbilirubinemia.

Water soluble vitamins

The B complex group of vitamins serve as coenzymes or coenzyme precursors. B vitamins are a group of eight water soluble vitamins. The B complex vitamins include thiamine (B1), riboflavin(B2), pantothenic acid(B3), niacin(B5), pyridoxine(B6), biotin (B7), folic acid(B9), cyanocobalamin(B12), inositol, choline, lipoic acid and para-aminobenzoic acid. B vitamins generally occur in protein –rich foods and dark green leafy vegetables. The B complex vitamins coexist in the same foods. The dietary requirement is between 10 – 400 mg of each daily. They help form red blood cells. Thiamine deficiency results in beriberi and riboflavin deficiency causes pellagra. The deficiency of pyridoxine causes anaemia and folic acid results in macrocytic anaemia. The B vitamins and vitamin C are often referred to as the “stress vitamins” because they are depleted by stress. B complex with Vitamin C plays a critical role in the body systems responsible for energy production, which helps to combat stress. The B vitamins are important for helping to reduce anxiety, depression, irritability, and nervousness. Most of the B vitamins, along with many other nutrients, are also removed when foods are highly refined or during the processing and cooking of foods.
Vitamin C
Vitamin C is also known as ascorbic acid or ascorbate and it exists in nature both as reduced or oxidised form called dehydroascorbic acid.  It can be destroyed by oxygen, alkalies and high temperature.  Recommended dietary allowance (RDA) for vitamin C is 90 mg/day for adult males and 75 mg/day for adult females. Vitamin C helps in the synthesis of collagen that holds muscles, bones, and other tissues together. Vitamin C also aids in wound healing, bone and tooth formation, strengthening blood vessel walls, improving immune system function, increasing absorption and utilization of iron, and acting as an antioxidant. It absorbs UV light and protects retina. The deficiency of vitamin C leads to scurvy, anemia, pains at the joints, hemorrhage from the mucous membranes of the mouth and GI tract.

Water-soluble vitamins are essential nutrients needed daily by the body in very small quantities. The B-complex vitamins can be found in a variety of foods like cereal grains and breads, as well as other foods such as meat, poultry, eggs, fish milk, legumes, and fresh vegetables. Vitamin C can be found in a many fruits and vegetables.

Vitamin therapy

Vitamins are essential organic substances usually supplied by foods. They are required by man in amounts ranging from micro-grams to milligrams per day. All the vitamins are essential for the normal growth, development and maintenance of the human body. They play an important role in the immune defense system. Vitamin therapy is a new and promising strategy for the treatment of certain chronic diseases. The therapeutically   new synthetic vitamin analogs with more potent, less toxic and long lasting effects are used in the treatment of cancers. However vitamins, vitamin analogs and vitamin mixture have been used and misused in the treatment of several diseases.

Saturday, April 19, 2014

Health benefits of dietary minerals

Dietary minerals are vital inorganic nutrients required by living organisms to remain healthy. There are two types of nutritional elements required in our diets:  macro/ major minerals and micro/trace minerals. Macro minerals   are those that are required in our diets in amounts greater than 100 milligrams per day.   Macro minerals make up about 0.01 % of human body weight. The seven macro minerals are calcium, phosphorus, magnesium, sodium, potassium, chloride and sulphur. Trace minerals are those that are required in amounts less than 100 milligrams daily. The nine trace minerals include iron, copper, zinc, iodine, fluoride, selenium, cobalt, chromium and molybdenum.

Occurrence and importance

There are over 90 naturally occurring elements. Of these only 26 are known to be necessary in humans. The four common elements, oxygen, carbon, hydrogen and nitrogen – make up 96% of the total weight of a mammal. The remaining 4% is the most abundant seven macro minerals. They constitute 60-80% of all the inorganic material in the body. Dietary minerals are essential for life and an insufficient supply may cause disease. They help form bones and teeth, aid in normal muscle and nerve activity, act as catalysts in many enzyme systems, help control water levels in the body and are components of enzymes and hormones and compounds like haemoglobin. Minerals like sodium, chloride and potassium are referred to as electrolytes because in water they can conduct electrical currents. They are essential for maintaining tissue fluid balance and the movement of nutrients and waste products in the cells.

Macro minerals

Calcium is a major constituent of bones and teeth and is the body’s most abundant mineral.  About 99% of the body calcium is present in the bones as calcium phosphate (calcium to phosphorus ratio is 2:1). Adequate intake of calcium for adults is 1000 milligrams per day whereas pregnant and nursing mothers require more calcium. Most calcium comes from dairy foods like milk, cheese and yogurt. Other food sources rich in calcium include bok choy, broccoli, kale and spinach.  A deficiency of calcium can lead to osteomalacia, osteoporosis, rickets, and tachycardia. Calcium ions are needed for membrane permeability, nerve conduction, muscle contraction and blood clotting.
Phosphorus is the body’s second most abundant mineral found in every cell and as part of DNA and RNA. The main sources of phosphorus include milk, cheese and meat. Adults need 700 milligrams of phosphorus daily.
Potassium is the third most abundant mineral in the body. Dietary sources of potassium include chicken, beef, pork, banana, orange, straw berries, pine apples, carrots and broccoli. It is the principal intracellular cation. It regulates acid-base balance and osmotic pressure of intracellular fluid. Adults require 4700 milligrams each day.
Sulphur is the fourth most abundant body mineral.  Sulphur is the constituent of proteins, amino acids, vitamins, insulin, heparin, and chondroitin sulphate. Eating protein rich foods like meat, fish, poultry, eggs, and milk provide enough sulphur and legumes give the required amounts of suphates for the body.
Sodium and chloride are the fifth most abundant minerals in the body and are both electrolytes that help to maintain fluid and electrolyte balance. Sodium is the major extracellular cation and chloride is the inorganic anion. Significant sources of sodium and chloride include table salt, soy sauce and processed foods. Adequate intake of sodium is 1500 milligrams for people from ages 19 to 50 and recommended upper limit for adults is 2300 milligrams per day. Adequate intake of chloride is set at 2300 milligrams with an upper limit of 3600 milligrams a day.
Magnesium is the sixth most abundant mineral in the body and last of the major minerals. More than 300 enzymes are known to be activated by magnesium ions. Magnesium works with calcium to assist in muscle contraction, blood clotting and the regulation of blood pressure and lung function. Dietary sources of magnesium include halibut, cashews and artichokes. Adequate intake for magnesium is 410 milligrams for males and 360 milligrams for females.

Trace minerals

There are 15 elements that make up less than 0.01% of the body of a mammal. The trace minerals are required in small amounts, hence the name ‘trace minerals’. At present, only 9 trace minerals have defined essential functions in humans.  Iron, zinc and copper are considered essential trace elements. A number other minerals have been suggested to be essential nutrients including arsenic, boron, bromine, cadmium, fluorine, lead, lithium, nickel, silicon, tin and vanadium. Trace minerals have four known roles in living organisms. They work in close association with enzymes, coenzymes and proteins. Some trace minerals donate or accept electrons in redox reactions of metabolic pathways. Some trace mineral especially iron, bind, transport and release oxygen in the body. Some trace minerals provides stability and structure to biomolecules.  Under the deficiency of trace minerals, the organism survives but with suboptimal health and wellbeing.  If the dietary intake is reached, the optimal health and wellbeing are regained.
Iron is one of the most essential trace elements. Iron is a constituent of haemoglobin and several intracellular enzyme systems like cytochrome oxidase, catalase, and xanthine oxidase. The body content of iron is 4-6g. The dietary requirement of iron is very small because the iron from break down of haemoglobin is stored in the liver and used again for haemoglobin synthesis. The dietary source of iron includes liver, kidneys, heart, spleen, egg yolk, fish and oyster.
Zinc is the second most abundant trace mineral. It is a constituent of zinc dependent enzymes e.g., DNA polymerase, alkaline phosphatase, carboxypeptidase etc. The body content is 2.5 grams and the daily requirement is 3 – 14 milligrams. Diet rich in zinc include red meat, fish and sea foods. Zinc deficiency in children results in growth retardation and skeletal abnormalities. Zinc deficiency also leads to complications of pregnancy and childbirth, low birth weight and poor growth in childhood, reduced immunocompetence, and increased infectious disease morbidity.
Copper is the third most abundant trace mineral in the human body. Body content of copper is 80-120mg. Copper is involved in the process of erythropoiesis, erythrocyte function and regulates erythrocyte survival. The daily dietary requirement is between 2 – 6 milligrams, which  is mainly obtained from  red meat, cocoa, shell-fish, water pumped through copper pipes and chocolates.
Selenium (ultra trace mineral) is the least abundant however the most toxic of all the essential elements. Dietary source is meat, fish and grains. The recommended intake for adults 50 - 200 µg/day as in USA however intake may vary in other countries where soil Selenium levels are low. Selenium deficiency occurs due to hemolytic anaemia and malnutrition.
Manganese (ultra trace mineral) is an important role in regulating metabolic processes which mainly include lipid and carbohydrate metabolism, bone and tissue formation, skeletal growth and reproduction. Over 50 Manganese dependent enzymes have been identified e.g., catalase, peroxidase, super oxide dimutase, 5’ nucleotidase, R Nase and glucosyl- and glactosyl-transferase.  Average daily body requirement is 2-5μg/day.
Cobalt (ultra trace mineral)-Biological function is limited. Vitamin B12 is the only cobalt containing compound. Beef, sea food and dairy products are major source of vitamin B12.
Iodine is necessary for the synthesis of the thyroid hormone. Enlargement of the thyroid gland occurs when iodine intake is less than 15 µg/day. Maternal iodine deficiency during pregnancy gives rise to cretinism in infants. Iodine deficiency during the foetal and early neonatal period adversely affects the growing brain.

The human body needs a number of minerals in trace (milligram) quantities. Other minerals are required in ultra trace (microgram) amounts. The dependence of many vital metabolic processes on trace elements confers upon them a physiologic importance analogous to that of vitamins. 

Friday, April 18, 2014

Nutritive value of dietary lipids

Lipid is a collective name for fats, fatty acids, oils and steroids. A lipid is an organic substance made up of carbon, hydrogen and oxygen that is not soluble in water.  The basic unit of lipids is a triglyceride synthesized from glycerol and fatty acids. Lipid is an essential dietary constituent in human nutrition because of its high calorific value (9 calories/gram). Lipids provide energy and help the body use vitamins. Lipids are essential for cell integrity and survival. Lipids are found in all cells of the body.
  WHO (2003) recommended the total fat intake for adults from the minimum (ideal) of 15 – 20% to a maximum of 30 – 35% for most individuals. The French, Greeks, Spanish, Inuit, Masai of Africa, Swiss and other cultures have thrived on diets with over 40 percent of calories from fat, much of it animal fat. Lipids are widely distributed in plants and animals.  Plants often store lipids in fruits and seeds. The form of lipids stored in animal tissues is varying widely in both quantity and type. The predominant substances in fats and oils are triglycerides.  Generally lipids are stored in adipose tissue, mesenteric tissue, and yellow bone marrow and around organs like kidney. The nervous system is rich in lipids like cholesterol, phospholipids and glycolipids. Dietary lipids supply essential fatty acids (EFA) to the body. They resemble vitamins and they cannot be synthesized by the body. Dietary lipids provide the medium for the absorption of fat soluble vitamins (vitamins A, D, E and K); a primary contributor to the palatability of food and are crucial to the early embryonic development.  Lipids serve as the concentrated fuel reserve ( e.g., triacyl glycerols) of the body and  the important  constituent of cell membranes and sex hormones.

 Dietary fat disorders

Nutrient deficiency in fat intake may cause the deficiency of essential fatty acids (EFAs).  EFAs are very important nutritional requirements for keeping good health. The deficiency of EFAs may increase the risk of getting affected by cancer, atherosclerosis, coronary heart disease, behavioural problems and chronic inflammation.
Nutrient imbalance   of fatty acids may result from the consumption of diets rich in omega – 6 and diets deficient in omega – 3 fatty acids. Excessive amounts of omega – 6 poly unsaturated fatty acids (PUFA) and a very high omega-6/omega-3 ratio, as is found in today’s Western diets, promote pathogenesis of many diseases including cardiovascular disease, cancer, and inflammatory and autoimmune diseases.
Nutrient excess diseases – eating excess calories causes fat to build up in the liver. It is a common liver complaint in Western countries. It affects about one in every 10 people.  The fatty liver disease leads to inflammation and liver damage. This condition is called non-alcoholic steatohepatitis, NASH or non-alcoholic fatty liver disease, NAFLD. The people with NAFLD have an increased risk of cardiovascular problems such as heart attacks and strokes.
Obesity means having too much of body fat. Obesity has been increasing rapidly throughout the world and incidence of obesity nearly doubled from 1991 to 1994.  Over two-thirds of adult in the United States are over-weight or obese and one in three Americans is obese. Being obese increases one’s risk of diabetes, heart disease, stroke, arthritis and some cancers.
Toxic fat syndrome (TFS) – is an epidemic primarily caused by a combination of 3 conditions: increased dietary bad fat consumption ( trans and high omega 6-fats), increased high glycaemic carbohydrate consumption(simple and starchy) and decreased dietary omega 3 fat consumption. TFS is the growing levels of toxic (soluble e.g., arachidonic acid,AA) fat in the blood stream. This toxic fat increases silent (deadly) inflammation, which is the cause of most diseases and chronic illness.

Dietary fats

 There are 3 different kinds of fats in foods such as saturated, unsaturated and transformed (trans) fats.  The saturated and transformed fats are called unhealthy or bad fats because the dietary intake of these fats contributes to increase cholesterol in the blood.  The dietary intake of unsaturated fats helps reduce cholesterol levels in the blood and so they are called healthy or good fats. The foods rich in saturated fats include butter, cream, bacon, palm oil and red meat. Saturated fats are solid at room temperature and come from both animal and plant sources. Animal sources are butter, lard (pork fat), suet (beef fat) or tallow, meat and poultry (especially the skin) and high-fat dairy products. Plant sources include palm, palm kernel and coconut oils, often found in commercial baked goods. Too much saturated fat can cause blood cholesterol levels to rise. Most foods contain a combination of saturated and unsaturated fats with one type of fat usually found in higher amounts.
 Fatty acids are long chain organic acids having usually from 4 to 30 carbon atoms. They have a single carboxyl group and a long non-polar hydrocarbon tail. Fatty acids represent 30–35% of total energy intake in many developed countries and the most important dietary sources are vegetable oils, dairy products, meat products, grain and fatty fish or fish oils.  Saturated and unsaturated fats have different chemical structures but contain the same number of calories per gram. The unsaturated fats are of two types: monounsaturated and polyunsaturated fats. Monounsaturated fat is found mainly in avocado, nuts and vegetable oils (canola, olive and peanut oils). This fat may help lower bad ‘LDL cholesterol’ and lower the risk of heart disease. Polyunsaturated fat is mainly found in vegetable oils (safflower, sunflower, sesame, soybean and corn oil)  and sea foods. Polyunsaturated fats are further divided into omega-6 polyunsaturated or omega-3 polyunsaturated fats and this terminology refers to the position of the double-bonds in the molecule. Omega -3 fatty acids are found in plants –soybean oil, canola oil, walnuts and flaxseeds. They are also found in fatty fish and shellfish as EPA and DHA. Salmon, anchovies, herring, sardines, trout, Atlantic mackerel, Pacific mackerel and Pacific oyster are high in EPA and DHA. Omega-6 fatty acids are found mostly in liquid vegetable oils like soybean oil, corn oil, and safflower oil.
Trans fats (transformed fatty acids) are formed during the process of hydrogenation of vegetable oils. This process is done to extend the shelf life of the food and stop the oil from spoiling. Shortenings and some margarines are produced by the hydrogenation process.Many commercially produced foods can have trans fats. This includes prepared cookies, crackers, cake, pizza dough, doughnuts, biscuits, refrigerated doughs, fried foods, and french fries. Small amounts of trans fats occur naturally in meat from ruminant animals well as in dairy products. Foods such as cakes, cookies, crackers and other snack foods often contain trans fats in the form of hydrogenated vegetable oil. Research claims that trans fats may increase LDL or bad blood cholesterol levels.

Management of  body fats

Fats have traditionally been recommended for minimal consumption. Saturated fat should be NO more than 7% of total calories. Trans fats from deep fried fast foods, cookies and snack foods should be reduced to the absolute minimum. Dietary intake of omega-3 fats is associated with a 40-65% reduced risk of death from cardiac events.Omega-3 fats may reduce the risk of heart rhythm problems and at high doses, reduce triglyceride levels. Studies have suggested that omega - 3 fats reduce the risk for heart attack and death from heart disease for those who already have heart disease (National Cholesterol Education Programme, 2001).  

Nutrition and food pyramids

Food pyramids are tools one can use to guide or assess dietary intake. Pyramids allow a person with limited nutritional knowledge to make sound decisions about what foods to eat.  The larger base of the pyramid represents the types of foods one should consume more often while the smaller top of the pyramid represents foods one should consume less frequently.

Wednesday, April 16, 2014

Therapeutic food proteins

Proteins are most abundant nitrogen containing organic substances of living organisms. They form enzymes, hormones, antibodies, transport and informational biological molecules. They are the principal structural (“brick and mortar” roles) and metabolically active compounds (“working horse” roles) found in the human body. They are the “beginners and builders of biochemical reactions.”  If carbohydrates and lipids are considered as the fuels of metabolic furnace, proteins can be regarded as forming not only the structural framework but also the gears and levers of the operating machinery.  Proteins constitute 50% of the cellular dry weight and some 17% by weight of the total lean body tissue.  The Food and Nutrition Board allows up to 35% of total calorie intake to be supplied by dietary proteins.The protein requirement of an individual is based on age, size and activity level.   Each gram of protein and carbohydrate provides 4 calories.Proteins not only provide energy but also build muscles and repair body tissues. The body stores leftover proteins as body fat.
 Five of the elements, carbon, hydrogen, oxygen, nitrogen and sulphur are found in all naturally occurring proteins. Other elements such as phosphorus, iron, iodine and magnesium are essential constituents of certain special proteins. Proteins are biopolymers made up of 20 different amino acids, and these 20 amino acids are the building blocks of different protein molecules. Nine of the amino acids are called essential because human bodies cannot synthesize them. The essential amino acids must be obtained only through diet. Amino acids are considered as the “currency” of protein nutrition and metabolism (Young, 2001). Often 300 or more amino acids found per protein molecule.

 Human protein nutrition

Proteins in human diet are derived from two main sources, namely animal proteins (e.g., egg, milk, meat and fish) and plant proteins (e.g., pulses, cereals, nuts, beans and soy products. Foods that provide all the essential amino acids are biologically complete proteins or high quality proteins. The high quality proteins can be obtained from meat, fish, poultry, eggs and dairy products. Foods that do not provide a good balance of all the essential amino acids are called biologically incomplete proteins or lower quality proteins. Plant foods contain incomplete proteins with regards to their amino acid composition. Most fruits and vegetables are poor sources of proteins. Some plant foods like beans, peas, and lentils, peanuts and other nuts, seeds and grains like wheat are better protein sources. A diet with incomplete proteins can be converted in to a complete protein diet, if two incomplete proteins (e.g., grains or legumes and nuts mixed together) are added together to produce what is called “complementarity of proteins.”

Protein - energy malnutrition (PEM)

The term Protein – energy malnutrition (PEM) is referred to as protein – calorie malnutrition and a fatal body – depletion disorder.  It develops in children and adults whose consumption of protein and energy is insufficient to satisfy the body’s nutritional needs. PEM applies to a group of related disorders that include marasmus (sickness of withering or wasting), kwashiorkor (protein malnutrition) and intermediate states of marasmus-kwashiorkor (protein deficiency). The effects of PEM leads to tissue damage, growth arrest and brain damage. Protein – energy malnutrition (PEM) is common on a worldwide basis in both children and adults (Stephenson et al 2000) causing the death of 6 million children a year (FAO 2000). In 2000, the WHO estimated that malnourished children numbered 181.9 million (32%) in developing countries. In India 70-80 million children under 5 years suffer from PEM and 4 million from severe forms of PEM. Protein deficiency affects all organs including the developing brain (Pollitt 2000), as well as the immune system (Bistrian1990) and gut mucosal function (Reynolds et al 1996). A serious depletion in the body mass protein can be life threatening with muscle loss, including loss of heart muscle (Hansen et al 2000).

Plant food proteins

Grain legume proteins
The seeds of legumes are rich in high quality protein and highly nutritious food resource.  Proteins in legume seeds represent from about 20% (dry weight) in peas and beans up to 38 – 40% in soybean and lupin.  Lupins are non-starch leguminous seeds with similar protein content to soybean at about 40% and high fibre content. The most abundant class of storage proteins in grain legumes are the globulins. The major staple foods such as beans, soybean, lentils, peas and chickpeas are all legumes. Legume seeds contain a number of antinutritional compounds (ANCs) which can be proteinous. The frequent intake of legumes can help control the lipid homeostasis and reduce the risk of cardiovascular disease (CVD). High fibre content, low glycaemic index and the presence of minor components such as Phytosterols, saponins, and oligosaccharides are claimed to control type II diabetes and digestive tract diseases.
Soybean proteins –Dry soybean contains approximately 35% protein, most of which is globulin, a storage protein. The major components of soy-globulin are glycinin and β glycinin both of which constitute about 80% of the storage protein. The nutritional value of soybean protein is one of the highest of vegetable proteins. The β glycinin has shown to lower serum triglyceride levels in human beings. Soybean also contains the biologically active protein components hemagglutinin, trypsin inhibitors, α amylase and lipoxygenase. A number of  studies indicate  the antidiabetic and antiobesity activities of soybean proteins. Soybean lectins have anticarcinogenic activity.
Cereal proteins
Wheat is the single most important food crop in the world. Wheat contains 8 – 15% protein depending on grain variety. The main storage proteins in wheat grains are the gluten proteins.  The protein content of maize is between 9 – 12%. Barley is the fourth most important cereal crop in the world after wheat, rice and corn. Barley constitutes 10 – 17% protein, slightly higher than other cereal grains such as wheat and rice. Rice is the second largest cereal crop in the world. Rice has the lowest protein content of all major cereals at 7 – 9% by weight. Sorghum is the fifth most widely grown cereal crop in the total world production (FAO 2009). Sorghum contains about 9 – 17% protein and is an underutilized food resource for human consumption.
Proteins from tuber and nuts
Potato is a versatile carbohydrate – rich food with a low overall protein content of 1 – 1.5% of tuber fresh weight. The potatoes provide complex carbohydrates, fibres, proteins, vitamins A, C and B complex and minerals such as copper, iron, magnesium and potassium. The juice of potatoes is excellent to cure gastritis and stomach ulcers.
Nuts are rich in energy and nutrients. They contain proteins, omega 3- fatty acids and dietary fibres. They also contain monounsaturated fatty acids (MUFA) such as oleic and palmitoleic acids which help to lower LDL or ‘bad cholesterol’ and increase HDL or ‘good cholesterol’. Nuts are the important sources of polyphenolic flavonoids antioxidants such as carotenes, resveratrol, lutein, cryptoxanthin etc. These compounds have been found to offer protection against cancers, heart diseases, degenerative nerve diseases and viral/ fungal diseases.

Animal  food proteins

Milk proteins
Milk is made of two proteins, casein and whey. Casein protein constitutes 80% and whey protein 20% of milk protein. Human breast milk is 80% whey protein. Milk for human consumption can generally be obtained from a number of domesticated animals such as sheep, goat, buffalo and cow. Fresh cow milk contains approximately 3.5 % protein, 80% casein, 15% whey protein as well as vitamins and lipids, all of which provide necessary ingredients of growth. Casein protein is recognized for its excellent amino acid content, slow digestion and anti-catabolic effect.
Bovine Whey   proteins
 Whey protein can be separated from the casein in milk or formed as a by-product of cheese making. There are 3 primary types of whey proteins: whey protein concentrate (WPC), whey protein isolate (WPI) and whey protein hydrolysate (WPH). Whey protein is considered as a nutritionally perfect protein with high biological value (BV), high protein efficiency ratio (PER) and high net protein utilization (NPV).Whey protein includes a mixture of globular proteins (lactoferrin, beta-lactoglobulin, alpha lactalbumin, bovine serum albumin and immunoglobulins), all essential amino acids and low lactose content. Whey protein has the ability to act as an antioxidant, antihypertensive, antitumor, hypolepidemic, antimicrobial and chelating agent. A number of clinical trials successfully revealed the therapeutic effects in cancer, HIV, hepatitis B, cardiovascular disease and osteoporosis. The higher glutathione levels in whey proteins have important immune, antioxidant and detoxification benefits (Report of International Whey Conference, Oct 1997).
Bovine colostrum
Colostrum is nature’s most nutrient dense zoonutrient. A mother animal produces true colostrum for only the 24 hours after giving birth. It is a non-milk immune supporting fluid. It is rich in highly bioavailable vitamins and minerals. Colostrum yield as high 40% immunoglobulins and immuno-modulatory  proline – rich polypeptides (PRPs).  It can help preventing anaemia, arthritis, multiple sclerosis and Alzheimer’s disease.Colostrum has growth factors that promote healing and anti-aging reponses.
Egg proteins
Eggs generally weigh about 57 grams.  The yolk proteins of an egg makes up about 34% of the liquid weight and the albumen accounts for about 66% of the egg’s liquid weight. A large  egg provides a total of 6.29 grams of high quality complete protein. The yolk portion provides 55 calories and the egg white contributes 17 calories. About 9% of the egg content is fat and is found in yolk.  Egg yolk carries the cholesterol, the fat and the saturated fat. The egg white contains bulk of proteins, folic acid, choline and minerals. The egg protein is a rich source of the essential amino acid leucine, which is important in modulating the use of glucose by the skeletal muscles. The egg is an excellent source of iodine for thyroid hormone synthesis, phosphorus for bone health, zinc for growth and wound healing and selenium for anti-cancer activity. The egg cholesterol is useful for the production of sex hormones, cortisol, vitamin D and bile salts.
Fish proteins
Fish is low in total fat, high in protein and rich in vitamins and minerals.  The protein content of most fish averages 15 to 20%. In addition to proteins and essential amino acids, fish contains significant amounts of lipids, vitamins and minerals.   Fish meat is a valuable source of calcium and phosphorus as well as iron, copper and selenium. Salt water fish have a high content of iodine. Both  fresh water fish of cold waters and  salt water fish contain significant levels of two  omega-3 fatty acids (N-3 fatty acids) such as EPA (eicosapentaenic acid) and DHA (docosahexaenoic acid). Some good choices of fish include salmon, trout, sardines, herring, mackerel, tuna and oysters. Fish oil is the best source of N-3 fatty acids which help reduce platelet activity (blood clotting) and plaque formation (atheroscelerosis) leads to heart attacks. The fish nutrients keep our heart and brain healthy. The USDA’s My Plate says that eating seafood (fish and shellfish) twice a week is good for our heart, brain and entire body.
Meat proteins

Foods in the meat, poultry and fish group are diverse, but all of them are rich in proteins. The amount and quality of protein in the foods varies. Animal meats like beef, pork and ham contain high quality proteins with all the amino acids. Besides proteins, these animal foods contain varying amounts of minerals such as iron, zinc and magnesium and vitamins E and B (thiamine, niacin, vitamins B6 and B12). The bad aspect of these foods is having substantial amounts of fat, saturated fat and cholesterol. Eating lean cuts of protein rich meats can help reduce the risk of cardiovascular disease and diabetes. Vitamins B6 and B12 help improve memory. Both niacin and zinc help protect against vision problems.

Food for thought

The American Health Association (AHA) strongly advised the people to follow a diet that contain a variety of foods from all the food categories and emphasized the consumption of fruits and vegetables, fat – free and low fat dairy products, cereal and grain products, legumes and nuts, fish, poultry and lean meats. Choose healthier sources of dietary proteins.