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Vitamins

Basic Nutrition



Vitamins are accessory nutrients, chemical compounds necessary for the body and its metabolism, that the body cannot make for itself but must obtain from foods. In spite of the fact that a good diet will supply all you need, a vast business has been built up on the fears and wishful thinking of a nutritionally gullible public. Fortunately, excesses of vitamins seem to be harmless except for those in the fat-soluble group, and even these become toxic only at huge dosage levels. A big serving of polar-bear liver can be quite poisonous, a fact long known to the Eskimoes and only lately understood by the biochemists. The toxic action results from the enormous concentration of vitamin A in it. Otherwise, even the vitamin crank who buys out the pill counter seldom runs any risk unless his enthusiasm centres on the fat-soluble group. Great excess of vitamin D can be harmful too.



Most of the vitamins are water-soluble, and this results in serious losses of them when foods are cooked for a long time in large quantities of water. But this is only part of the reason for using minimal water and short cooking times for vegetables; the result tastes better. Another pernicious custom in vegetable cookery is the addition of baking soda, which tends to destroy some vitamins without any compensating virtue we know of. The cook who boils the peas for forty minutes in a quart of water with soda added should be indicted for assault and battery on the taste as well as for negligent nutricide.

We defy anyone but a metabolic freak to suffer from vitamin deficiency while following the admonitions and menus in this book. As far as possible we have emphasized foods that are good sources of vitamins and have provided cooking methods that conserve them. The menus offer a great variety of foodstuffs, and a diet of such varied food alone is a guarantee that you will get not only all you need of the known vitamins but also those still to be discovered and not yet stocked in the chemist's shop. Finally, the reduction in the "empty calories" of fats and oils that is at the heart of this book means replacing those calories with foods that offer more than calories and greasiness.

In other words, you do not need to know much about vitamins to get an abundance of them. But the notes below on the several vitamins may clarify a few points.

Fat-Soluble Vitamins

The fat-soluble vitamins, A, D, and E, are stored in the body for a long time, so it is unnecessary to insist that these be supplied liberally every day or even every week. For adults the most important of these is vitamin A. But a diet devoid of A (which is not easy to devise) produces no sign of harm for many months if you have been well nourished previously. Once upon a time many people were frightened into buying vitamin A concentrates because they did not see very well in the dark or had frequent colds. Research has de-emphasized these ideas. Vitamin A deficiency to the point of night blindness is certainly very rare in this country. As for warding off colds and other infections with vitamin A, we wish the Food Standards Committee would do more to stop excesses of advertising on this claim.

Vitamin A as such is supplied in liver and shellfish, and we advise you to eat such fish as herrings not less than once a week and liver at least several times a month. But your diet will also provide, in the bright-coloured fresh vegetables we recommend so highly, large quantities of carotene which is converted into vitamin A in the body. Severe vitamin A deficiency can cause dry skin, but if this is your trouble rub a little lanolin cream into your skin. The next step is a visit to your doctor, not to the chemist. As for night vision, try avoiding bright lights before you go out in the dark.

Vitamin D prevents rickets, and rickets is an affliction of childhood when the bones are developing. Whether adults need any vitamin D is not known, but if it is really needed there are two good sources at hand. Fish and particularly herrings are the most abundant natural source. But probably the most truly natural source of vitamin D is that made in your own body when your skin gets a little sunshine. Small amounts of D are provided in meats, also.

Vitamin E has been the subject of more nonsensical claims than most vitamins - which is saying a lot. With great labour you can devise, for animals, a diet devoid of vitamin E, and if you maintain rabbits on this long enough they have muscular disorders and become sterile. The latter point was seized on hopefully by some would-be exploiters but, alas ! dosing with vitamin E and wheat-germ oil seems to be only one more futile gesture in the age-old search for fertility and virility.

Vitamin E has not been shown to be necessary for man, probably because all human diets contain more than enough for minimal needs. One small but vocal clinic in a nearby country has made a lot of noise about the use of vitamin E in a variety of ailments including coronary heart disease. They have dispensed enormous amounts of E but so far have convincingly demonstrated only their own monomania to medical scientists. If you are concerned about vitamin E, note that the cooking and salad oils we recommend, such as corn oil and cottonseed oil, are loaded with it. Eat as we suggest and you will get several times more vitamin E than your neighbours.

Vitamin K Vitamin K, the anti-haemorrhagic factor, is apparently a vitamin only in the sense that it needs to be supplied from outside the body in certain uncommon disease states. Vitamin K is present in many foods, notably in spinach, cabbage and pork, but equally important may be the fact that this vitamin is synthesized by bacteria naturally in the digestive tract. Doctors sometimes prescribe vitamin K for pregnant women just before time for delivery as a precautionary measure. Another use for vitamin K is to counter overdosage of anti-coagulant drugs, but here again vitamin K is for your doctor, not you, to worry about.

Additional topics

Staying well and eating well