WELL BALANCED DIET

Taranaki Daily News, 10 August 1934, Page 3

WELL BALANCED DIET

VALUES OF VARIOUS FOODS CORRECT GOVERNING PRINCIPLES. 2 ADDRESS BY DR. J. S. CHURCH. RED CROSS SOCIETY. The importance of knowing the principles governing correct diet drew a good audience to the Red Cross Society’s rooms last night, when Dr. J. S. Church delivered an interesting address upon the subject. All food was divided into three main classes, protein, fats and carbohydrates, known as the proximate principles of diet.

Dr. Church considered the separate functions of the three classes of food. About half of protein provided energy and half was needed for purposes of repair. In general its presence speeded up the burning of all food. Fat was .a concentrated food containing certain vitamins but it could be done without because the body could manufacture its own fat from carbohydrates. This latter was the fuel par excellence of the body, furnishing more than 50 per cent, of energy. It was also essential to aid in the burning of fats which, if not complete, caused the formation of poisonous substances. A normal diet for a man might be said to be constituted of 100 grams protein, 100 grams fat, and 500 grams carbohydrate, furnishing in all about 3390 calories. These ■ figures, however, varied to a considerable degree. Accessory food factors and vitamins were dealt with by the speaker. In spite of the work that had been done it was impossible yet to say why they produced their effects. However, he enumerated several and gave their properties. Though these potent substances were so widely spread among natural foodstuffs that complete absence of any one of them was rarely found, there was often a relative lack,, especially where. civilisation had laid its refining touch on the production of food. “In many ways,” he said, “the body may be looked on as an engine and the food as the fuel to keep, it going. It. is a very simple matter to work out the amount of . heat given off when any substance is burned. This has been done for all classes of food stuffs and their heat producing value has been determined. In all engines there is always a tremendous waste of fuel and the human body is relatively efficient in that 25 per cent, of the energy produced is available for work.

“It is obvious that an idling engine requires less fuel than one doing hard work, so it is equally obvious that a person at rest in bed requires less food than one doing hard work. The question, however, is complicated by. the fact that food is not only fuel but also contains substances required for the replacement of the wear and tear on the machine, which is going on all the time. In the growing body there is also the question of providing the material required for growth so that children require relatively more food and more sleep than adults. A PERSON’S REQUIREMENTS. “Generally the energy requirements of an adult person at rest are about 2100 calories daily, while for a manual worker 3100 calories are needed. It is possible to live for a time on less. During the war the people of the central powers were reduced to 2500 ' calories daily but it was found that after a period of apparently favourable.'results, marked deterioration in the health and endurance of the population soon evident. It is often pointed out that we could live on much less. food than we eat. That is so but the minimum is not the optimum any. more than the maximum is.. The middle way is better than either extreme.” ' Proteins, and carbohydrates had a calorific value of 4.5 while fat had a value of 9. Theoretically, considering the body as an engine and food as fuel, the necessary caloric value could'be made up entirely’of one class of food. Actually this was impossible, for several reasons, and it was found that definite proportions of each class of food, were required by the body to retain perfect health. The Japanese averaged only 30 grams of fat daily, and in general the. amount eaten increased with the income. The Eskimo on the other hand lived largely on fat so it was obvious, that great extremes were possible. “From America, the land of cults and quackery,” said the doctor, “come weird ideas on diet. Vegetarianism is a well known fad which does little harm except, to fill its devotees with wind and selfrighteousness, but the strictest , vegetarian allows himself milk, and eggs and butter, which are animal products, and contain animal fats and. proteins. WATER A MAIN ESSENTIAL. “Although the bulk of our diet is composed of the proximate principles certain other things are essential. The most obvious of these is water. Every thing we digest has to be dissolved in water. In addition we lose a lot of water via the skin and lungs during the day and this loss has to be made up. About three Nnts of fluid; daily should be taken in addition to what is contained in the food. “The next most obvious requirement is for the replenishment of the mineral constituents of the body. Mineral salts are necessary. We usually take ample common salt but our diets are often lacking in other salts. Calcium salts are needed for bone making. Phosphorous' is required, iron and iodine are necessary. Milk is a food which supplies calcium, wholemeal phosphorus, meat and vegetables, iron, fish and vegetables iodine.

“Symptoms of vitamin deprivation are. not common in this, country except, for rickets which are . certainly common in a mild form. But there is no doubt that many poor people and rich women intent on slimming do suffer from minor degrees of vitamin deficiency. . “There is no need for. anyone to worry about the amount of vitamins present in the food. If an ordinary common' sense . diet is used there will be plenty of vitamins and calories, and the proportion of the various principles will be reasonably accurate. It is when we start to interfere with what nature has taught. us through the generations that we find ourselves making grave errors, . DANGER OF LOP-SIDED DIET. “Milk, butter, cream,. potatoes, green vegetables, beans and peas together with meat and fish and eggs will supply us with all the vitamins required. Jt is only the faddist who will not eat.meat, milk or eggs, or whatever it may be, and who therefore lives on a lop-sided diet, who is liable to suffer from deficiency disease. Of course there are some people so lazy and foolish that they live on tinned food—probably because they can get more credit from the grocer than from anyone else. I have actually been in a sharemilker’s house in Taranaki, where condensed milk only, was used! People who live on tinned fruit, tinned milk, tinned meat, tinned jam and white bread are living on an obviously artificial diet; and as a rule they have poor health. I The children are rickety and suffer from | colds and bronchitis. “This brings me to the vexed question

of white or brown bread. There are many people who do not like brown bread or wholemeal bread and provided they are eating a well balanced diet, there is no need whatever for them to stuff themselves with a food they dislike for the sake of a few vitamins. In fact it is practically only the antipellagra vitamin which is found in wholemeal bread and not in white bread and pellagra is practically unknown. On the other hand there is much more waste with wholemeal bread than with white bread.”