The Rest of The Journey

New Zealand Listener, Volume 9, Issue 229, 12 November 1943, Page 18

The Rest of The Journey

(Written for "The Listener’ by DR.

MURIEL

BELL

Nutritionist ‘to the

Health Department)

\X JE have followed in the two previous articles what happens to our food: so far, it has been chewed, swallowed, and dealt with by the stomach. When it has been reduced to a fine state, it leaves this organ, a little bit at a time. Next it meets with three powerful pancreatic ferments which digest it still further, and which are aided by the bile that has been accumulating in the gallbladder. The finishing touches to this process of digestion are put on it by the secretions from the small intestine. As the final chemical units are formed, they are absorbed by the activity of the small intestine-it is not a mere transference through the wall of the intestine, but an active process de‘pending on the proper functioning of the cells. Sometimes, in certain individ‘uals, these cells are not in good form‘they fail to deal with the absorption of ‘the foodstuffs in the proper manner. Thus it comes about that certain persons require a better diet than the average person; if the intestinal wall is offered a richer supply of food nutrients, there is a better chance of getting some of them passed through into the bloodstream, Thus also is explained the circumstance that a small minority suffer from such deficiency diseases as pernicious anaemia, pellagra, or sprue, even when their dietary is as good as yours. It is this variability among human beings which makes it difficult to formulate rules for a whole population, and which makes it desirable to err on the safe side by including in your diet such foods as liver, from time to time; and vegétables, wholemeal bread, and milk in considerable proportions and as a regular precaution, When most of the food value and 90% of the fluid has been extracted and absorbed, the remainder is passed on into the large bowel. Here there is a further absorption of water, and there is a certain amount of friendly bacterial action. The quantity of residue left depends on many factors, chief of which are the quantities of vegetable, of fruit, and of whole-grain cereal in the diet. Lest anyone has any doubt about this, experiments have recently been done on human beings which show that when bread forms a considerable proportion of the dietary (as it does among the majority of those who do muscular work) a change from white to wholemeal bread actually doubles the quantity of this residue, As to the bacteria, they play a very important part in the health of herbivorous animals. But there is some recent evidence, too, that we of the omnivorous group are indebted to bacteria. For when a certain member of the new sulpha drugs which kills bacteria in the intestine is given over prolonged periods, the health of omnivorous animals suffers because the friendly bacteria have been destroyed. This association of two forms of life for their mutual benefitwhat the biologists call "symbiosis"is known to occur with plants of the legume family; but there is a close interaction between soil bacteria in general and the plants that grow in the soil, And this principle of mutual aid extends to human beings.