Monday, July 28, 2014

Foods for better brain health

The brain is the most delicate and complex organ of the human body. Human brain is unique, electrochemical supercomputer which is far greater in complexity, speed and sophistication.   Isaac Asimov quoted, “The human brain then is the most complicated organization of matter that we know”. According to a saying, the brain is wider than the sky and deeper than the sea. The brain is the command and control centre of human body.  The brain is the seat of intelligence, emotion and memory.  The brain is the organ of one’s personality, character and intelligence. The brain receives, registers and processes information.   The brain initiates movements and behaviours. Neurons are the basic building blocks of the brain. The human brain contains more than one hundred billion neurons (nerve cells).  Each of the neuron has about 60,000 to 100,000 synaptic connections and has a total number of synaptic connections of about 1027 . The human brain is connected to 30,000 miles (50,000 kms) of nerves.  The neurons are arranged end to end and the neurotransmitters transfer signals across the gaps (synapses) of 0.02 to 0.05 microns. The brain is a dense web of interconnecting synapses. Neurons communicate using electrical impulses. The neurons actually make up less than a tenth of the cells in the brain. The other 90-98% by number is glial cells, which are involved in development and maintenance. The human being has the highest ratio of weight of the brain to the total body weight.  The human brain weighs about 1.5 kgs, about 2 percent of body weight. The brain requires 15 percent of the blood, 40- 50 percent of the oxygen supply and 25 percent of the calories we consume. A 15 sec blockage of blood to the brain will result in unconsciousness. The brain cells are sensitive to oxygen availability. The brain needs a well-balanced, low-cholesterol and low- saturated (animal – fat) diet.

Brain chemicals

Neurotransmitters are the chemicals in our brains that regulate our feelings and emotions. Different neurotransmitters perform different functions in the body. There are 183 currently known transmitters.The neurotransmitters are primarily synthesized in nerve terminals. The master neurotransmitters are serotonin and the catecholamine group which consists of dopamine, norepinephrine and epinephrine. Neurotransmitters are made from amino acids. For example epinephrine and dopamine are made from phenyl alanine. Serotonin is made from tryptophan. Amino acids are generally abundant in high protein foods such as dairy products, eggs, legumes, fish, meats, nut, poultry and soybeans. Amino acid therapy is the use of supplemental amino acids to help balance body’s normal supply of amino acids and should be undertaken under the supervision of a doctor.
Acetyl choline is a neurotransmitter that is believed to play a crucial role in memory. Gamma amino butyric acid (GABA) (natural tranquilizers) inhibits message transmission and helps to control brain overload. Serotonin is a neurohormone that acts on the overall operations of the brain. It is our natural anti-depressant and sleep promoter. It helps to control the general states of alertness. Catecholamines are our natural energisers and mental focusers.  Dopamine is a neurohormone that helps to control physical movement.  Endorphins are neurohormones (feel – good chemicals) that serve as a source of pleasure and reward as well as a means of reducing one’s awareness of pain and irritation.

Brain cell death

A process called oxidation destroys brain cells and creates free radicals as a by-product. Free radicals are killer molecules that kill cells including neurons and destroy neurotransmitters – which are the chemicals that transmit electrical messages from one brain cell to another.

Brain glucose

 The human brain is metabolically most active organ of the body.  It uses about 20-30% of a person’s energy intake at rest. Glucose is the brain’s sole source of energy.   The tight regulation of glucose metabolism is critical for brain physiology. The brain functions such as thinking, learning and memory are closely dependent on glucose levels and how effectively the brain utilizes glucose. If glucose becomes inadequate, neurotransmitters are not synthesized and communication between neurons breaks down.

Brain water

Human brain is very soft and composed of 80% water, which means that the most important requirement of good brain health is hydration. Dehydration causes shrinkage of brain tissue and expansion of fluid filled cavities in the middle brain. Dehydration can impair short term memory, visuomotor functioning and psychomotor functioning.  Extreme dehydration can results in delirium which causes confusion, inability to speak or think coherently, disorientation and hallucination. Dehydration is a major contributor to increased production of free radicals and premature aging.

Brain fats

The brain is composed of about 60% fat and brain cells is about 70% fat. The fats we eat directly affect the structure and substance of the brain cell membranes. About 20 % of the fat in our brain is made from essential fatty acids omega-3 and omega-6 fatty acids.  The balance between omega-3 and omega – 6 fatty acids seems to be critical for the brain’s structure and function. Human brain has special requirement for fatty acids. DHA (docosahexaenoic acid) accounts for up to 20% of total fatty acids in the grey matter and is the most abundant PUFA in the brain. DHA insufficiency affects membrane fluidity, serotonin transport, gene transcription, and inflammation and energy metabolism in the brain.  DHA exerts a neuroprotective action by preventing oxidative damage and inflammation.
Many nerve fibres are surrounded by myelin sheath, which speeds up the transmission of nerve impulses. Myelin is made up of various fats, fatty acids, phospholipids, cholesterol and protein. In fact 75% of myelin comes from fat. Choline enhances memory and promotes clear thinking.

Brain vitamins and minerals

The brain needs vitamins and minerals. B-vitamins help to maintain and build healthy brain cells. Vitamins B1, B6 and B12   play a valuable role for good brain health. Vitamin B1 (thiamine) helps in the conduction of electrical impulses within the brain.B6 (pyridoxine) is needed for the production of the neurotransmitter serotonin, which improves mood and B 12 (cobalamin) which is a constituent of the myelin sheath. Mineral ions such as sodium, potassium, calcium and magnesium must maintain in critical balance.

Brain healthy foods

Physical exercise is most important food for the brain. Foods that have over 90% water content like grape fruit and water melon contain essential nutrients and electrolytes required to maintain proper hydration and optimal brain function.  Drinking beverages like coconut water and fruit juices effectively maintains optimal hydration and electrolyte balance.
Since glucose is the fuel for the brain, the blood glucose level has to be properly maintained. Complex carbohydrates are the best brain foods. Complex carbohydrates like whole grains, vegetables, beans or lentils – take longer to digest and slowly release potential energy.  Refined starch (white breads, white rice and pasta) impairs mental function.
Human brain needs oils and fats to function. Two essential fats especially critical to the brain are the omega – 3 and omega – 6 fatty acids. Foods high in omega- 3 fatty acids are important to maintaining brain health. Certain fish including salmon, mackerel, herring, sardines, tuna, anchovies, white fish and sable fish are good sources of omega – 3 fatty acids. Bad fats (saturated fats) inflame the brain. Trans fat is labelled as potentially the risk for Alzheimer’s disease by almost 50%.
Vitamins B 1 can be obtained from whole grains, nuts, meat and eggs. Vitamin B6 can be obtained from eating fish, poultry, eggs, whole grains and nuts. Vitamin B 12 can be obtained from meat, fish, dairy products, eggs and yeast extract.
Foods rich in vitamin C, Vitamin E and beta- carotene appear to reduce cell damage including brain cells. Vitamin C is found in citrus fruits, broccoli, Brussels sprouts and straw berries. Vitamin E is found in vegetable oils (corn, canola, sun flower, soybean and olive oils), nuts and leafy greens. Beta – carotene is found in sweet potatoes, carrots, kale and spinach. Folic acid is an essential ‘brain food’, which is critical for normal nerve function. Folate works with approximately 20 different enzymes to build DNA. Folic acid is found in leafy green vegetables, bananas, orange, and straw berries.
Iron – rich foods improve mental alertness and energy levels. Lean sources of red meat, poultry, spinach, beans, dried fruits and whole grains are excellent sources of iron. Selenium is linked to balance of moods, which is available in whole grains, rice, meat and sea weeds.

Essentials of brain health

1. Be physically active
2. Eat a healthy and balanced diet
3. Avoid saturated fats and caffeine
4. Listen to your body
5. Keep your mind active
6. Maintain good heart health and healthy body weight
7. Protect your head from injuries.
8. Calorie restriction can enhance learning and memory.

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