Diet plans come in many shapes and forms these days - heart friendly, low-fat, low-calorie, low-sodium, obesity-fighting. Here's a lesser known one - brain-boosting. More and more doctors, nutritionists, dieticians and neurologists are underscoring the impact of certain foods on brain functioning. These foods, they say, improve mental dexterity, decelerate age-linked memory loss, alleviate depression and even help prevent ailments like Parkinson's and Alzheimer's.

"The human brain," explains neurologist Dr S K Motiani, Senior Consultant, Kailash Hospital, NOIDA, "requires a large amount of oxygen to function well. And pretty much like the rest of the body's organs, it undergoes regular tissue wear-and-tear. So, to rejuvenate brain tissues - and keep the brain well-replenished - one needs the correct diet and supplements."

In fact, a study conducted by the Department of Medicine at the All-India Institute of Medical Sciences, New Delhi, in 2004 - and later published in the US medical journal 'Clinical Endocrinology' - underscores this crucial brain-diet connect. It says that what humans consume directly affects their brains. Hence, while an oxidants-rich diet (items that accelerate oxygen supply to the brain) is good for the grey cells, the study warns against food that could lead to an escalation in blood fats (triglycerides) and, hence, reduced blood flow to the brain.

"All the nerves in the body," elaborates Motiani, "are covered by a fatty layer. These are essential fatty acids, which need to be kept lubricated by the right kind of diet. Also, since brain cells are constantly regenerating themselves, any kind of diet deficiency can lead to permanent nerve damage in the brain. In addition, the food you eat directly affects the neurotransmitters or chemical messengers in your brain, thereby influencing your mood too."

So what is the 'right' kind of brain diet? "Red meat, processed or refined foods and junk food are a strict no-no, as they are damaging to both brain and body," says Dr Anika Chawla, a Mumbai-based clinical nutritionist. "A high-fat diet leads to a surge in triglycerides, which apart from causing lethargy can also impact memory and recall."

Hence, Chawla advocates foods like nuts, broccoli, carrots, green leafy vegetables and citrus fruits, which provide antioxidants to the body and help slow down cell damage. Ditto fruits like strawberries, grapes, plums, red cabbage and cherries, which are teeming with anthocyanins that inhibit formation of blood clots. Dry fruits like almonds, walnuts and peanuts too are fibre-rich, while healthy oils (cold pressed oils like olive, for example) also help boost brain power.
As a rule of thumb, doctors advise that a diet rich in Vitamin B-complex, B1, B2, B6, B12 and folic acid - such as cereals, pulses, milk, brown bread, bran and wholewheat - can enhance brain function.

But what foods do we need to avoid? Most doctors warn against junk food rich in saturated fats, which lead to an increase in triglycerides in the body, thus leading to a rise in LDL (low density lipoprotein) or bad cholesterol. And burgers and fizzy drinks are not the only villains. Indian foods like pooris, paranthas, salted savouries, bhajias and the like are just as bad. "When we talk of junk food, it is misconstrued as just what fast food outlets dispense. Indians, though, are used to eating so many harmful and empty calories through our own cuisine that we need to be educated about that too," explains Chawla.

Also high on all nutritionists' advice list are apples. This advice is backed by recent research at the University of Massachusetts, which reinforces that consuming apples (particularly the juice) protects against cell damage (and thus against age-related memory loss). "Even in test animals that were highly vulnerable to Alzheimer's disease and other dementias, the study found that consuming apples in conjunction with a balanced, fibre-rich diet, could shield the brain from the ill-effects of oxidative stress," notes Thomas B Shea, Director, UOM Centre for Cellular Neurobiology Research. The study, which was recently published in The Journal of Alzheimer's Disease, reports that stronger mental acuity (triggered off by the apples' antioxidants) resulted when aged mice consumed the human equivalent of two to three cups of apple juice per day!

Since the brain consumes more oxygen than any other body tissue, an iron-rich diet can also pay rich dividends. Iron is found abundantly in green leafy vegetables, like spinach, cabbage, amla (gooseberry), fenugreek and lettuce leaves. "However," exhorts Dr Ravinder K Tuli, Senior Consultant, Department of Holistic Medicine, Indraprastha Apollo Hospital, New Delhi, "eating iron-rich food items per se will not help. To aid iron absorption in the body, vitamin C is critical. So one must consume citrus fruits, lemons, green chillies or its supplements to enhance the blood's capacity to carry oxygen to the brain." According to Tuli, vitamin C combats stress, augments cell development and synthesises amino acids to enhance nerve function.

Besides these, beta-carotene (converted to Vitamin A in the body, and present in vegetables such as carrots, sweet potatoes, spinach and fruits such as apricots), folic acid (abundant in green vegetables), whole grains, bananas, seafood, pulses, cereals and wheatgerm are all brain food. The potassium-packed banana is particularly good for students as it helps transport oxygen to the brain, thereby enhancing one's studying power. Moreover, the body converts its protein - tryptophan - into serotonin, the hormone that fobs off depression. Also important for mental agility - advise nutritionists - are the Omega-3 fatty acids found in fish. These fatty acids not only improve recall but are known to possess remarkable curative powers in treating brain-related illnesses, depression and heart disorders too.

"Also," advises Chawla, "apart from what you eat, how you eat is also of critical importance if you want your brain to keep ticking well. One should take smaller, more frequent meals throughout the day rather than three bulky ones. And follow the reverse culinary pyramid - with breakfast being the heaviest meal of the day and dinner the lightest."

In other words, eat right to think smart!