It is a well-known fact that nutrition plays a vital role in the maintenance of health and formation of disease. There are certain diseases where nutrition plays a direct role in altering the course of the disease e.g. peripheral neuropathy. There are other diseases e.g. cerebrovascular accidents where nutrition affects the risk factors significantly so as to change the entire prognosis of the disease. And there are still other diseases (like Parkinson's disease, motor neurone disease and multiple sclerosis) where good nutrition plays a vital role in supporting the patient through the chronic progressive course. Nutrition is also important in unconscious patients, who have either had a head injury or a cerebrovascular accident or have been operated for a brain tumour. Furthermore it is now commonly seen that even mentation i.e. our thinking processes, are governed by the kind of food we eat.

The issue before us is—What kind of nutrition is good for the neurological patient—vegetarian or non-vegetarian? A difficult question to answer, indeed. There is scant research data implicating either vegetarian or non-vegetarian diets directly in any disease process concerned with the nervous system.

Starting with the thinking process—mentation and intellectual activity—there is a long list of intellectuals in history who made an indelible mark in their times and who were vegetarians. They were Isaac Newton, George Bernard Shaw, Shelley, Milton, Voltaire and more closer to home, Mahatma Gandhi, Rajendra Prasad, Rajagopalachari, Lal Bahadur Shastri and many more. It is widely believed and it is probably true, that vegetarianism does promote intellectual activity of a very high order. Mahavira, Gautam Buddha and Saints of Hinduism all advocated vegetarianism.

Like intellectual activity, even physical functions seem to be better preserved in vegetarians as compared to non-vegetarians.

For the sake of convenience the relationship of a vegetarian diet to specific neurological disease can be discussed individually.

Migraine

Headache is one of the commonest complaints in outdoor neurological practice. Migraine ranks second only to tension headaches. Migraine has a very close relationship to the kind of food we eat. The substance implicated in causing exacerbations is tyramine. Tyramine is formed by the decarboxylation of the amino-acid tyrosine by bacteria and enzymes. Hence it is best to avoid foods that contain tyrosine. These are aged meats and meat products, fish, cheese, brinjals, pods of beans, alcoholic beverages (wines, ale and beer). The entire range of nonvegetarian foods seems to be implicated thus suggesting that a vegetarian diet may be a more suitable diet for a migraine subject.

Cerebrovascular Accidents (C.V.As.)

It would not be wrong to say that this group of diseases comprises 40% of all hospital-based neurology practice. This is a significant disease as it is responsible for maximum morbidity and mortality. Its medical, social and economic implications are tremendous. C.V.A s . are situations that lead to paralysis of limbs and disturbed mental function. Though nutrition does not affect C.V.As. directly it affects each and every risk factor and hence plays a large role in preventing C.V.As.

The main risk factors for C.V.A. are:

1. Hypertension
2. Diabetes mellitus
3. Hypercholesterolaemia
4. Alcoholism and cigarette smoking
5. Obesity
6. Pre-existing heart disease

There is ample evidence in the nutritional literature that a vegetarian diet is beneficial in the treatment and the prevention of hypertension, diabetes mellitus, hypercholesterolaemia, obesity and that vegetarians are less inclined to tobacco and alcohol abuse. Hence the corollary is that vegetarian diet is beneficial for the prevention of cerebrovascular accidents.

Multiple Sclerosis, Motor Neurone Disease, Parkinson's Disease and Other Chronic Progressive Diseases of the brain and spinal cord have been found by some to have a nutritional basis. For instance, some workers have suggested that multiple sclerosis can be benefitted by a diet high in essential amino acids. The sources of essential amino acids e.g. safflower, sunflower, soyabean, corn oil, walnuts, peanuts, almonds are all vegetarian. Though no double blind trials can be quoted it is our observation that patients suffering from the above mentioned chronic neurological problems are more comfortable on vegetarian diets than on non-vegetarian diets.

The significant relief in constipation, which is a serious problem in all these patients, is probably due to the high fibre content of the vegetarian diet. Those patients who consume more fruits and vegetables are also less prone to the chronic infections to which this group of patients are highly susceptible. This may be attributable to the rich supply of vitamins, minerals and trace elements obtained from fruits and vegetables, which are essential for the integrity of the immune system.

Peripheral Neuropathies are said to improve with the help of foods containing high amounts of vitamins, minerals and essential fatty acids. These elements are in abundance in uncooked vegetarian food e.g. fresh fruits, raw vegetables (for vitamins and minerals) and nuts like almonds, walnuts, peanuts (for essential fatty acids). Though there is no significant proof of their efficiency by themselves, fresh fruits, raw vegetables and other similar foods improve the general well-being of the patient and thereby enhance overall recovery.

These and many more instances in daily practice, and in the scientific literature, definitely suggest that a vegetarian life style is superior to a non-vegetarian life style from the angle of prevention of disease. Vegetarian diet also plays a good supportive role in the treatment of many chronic, progressive neurological diseases. Hence, taking into consideration the available data, it would not be incorrect to conclude that vegetarianism is beneficial not only for the prevention of many neurological diseases but also in the treatment and support of some of the diseases.

REFERENCES

1. Alter A, Yamoor M & Marshe M:-Multiple Sclerosis & Nutrition, Arch, Neurol, 1974, 31:267.
2. Hanington E, Prelirninary report on tyrannine headache, Br. Med J. 1967, 2:550.
3. Kohlenberg R. J., Tyramine sensitivity in dietary migraine: a critical review. Headache, 19S2, 22:30.
4. Krause M.V. & Mahan L. K., Food, Migraine, Nutrition and Diet Therapy, 7th Edition, 1984
5. Mertin J. & Meade C. J., Reference of Fatty Acids in Multiple Sclerosis: Br. Med. Bull. 1987, 33:67.
6. Olson W. H., Diet & Multiple Sclerosis Postgrad Med. 1976, 59:219.