Published Science

The muscle glycogen content of the quadriceps femoris muscle was determined in 9 healthy subjects with the aid of the needle biopsy technique. The glycogen content could be varied in the individual subjects by instituting different diets after exhaustion on the glycogen store by hard exercise. Thus, the glycogen content after a fat + protein (P) and a carbohydrate-rich (C) diet varied maximally from 0.6 g/100g muscle to 4.7 g. In all subjects, the glycogen content after the C diet was higher than the normal range for muscle glycogen, determined after the mixed (M) diet. After each diet period, the subjects worked on a bicylce ergometer at a work load corresponding to 75 per cent of their maximal O2 uptake, to complete exhaustion. The average work time ws 59, 126 and 189 min after diets P, M and C, and good correlation was noted between work time and the initial muscle glycogen content. The total carbohydrate utilization during the work periods (54-798 g) was well correlated to the decrease on glycogen content. It is therefor concluded that the glycogen content of the working muscle is a determinant for the capacity to perform long-term heavy exercise. Moreover, it has been shown that the glycogen content and, consequently, the long-term work capacity can be appreciably varied by instituting different diets after glycogen depletion

THERE is considerable evidence relating nutrition, presumably through its influence on the levels of circulating lipids, to the relentless progression of atherosclerotic vascular disease and to the well known clinical sequelae that plague contemporary, highly developed societies. Unfortunately, it is difficult to unravel the precise and unique role of diet or of blood lipids in a disease in which a great many other factors are known to be involved — a severe limitation to descriptive clinical and epidemiologic studies. On the other hand, since dietary alterations can significantly influence blood lipids, nutrition may be of some importance in the treatment . . .

Viable counts were made of the bacteria and yeasts in different parts of the stomach and small intestine, and in the caecum, colon, and faeces of 3 or more animals of each of 15 homothermic and 5 poikilothermic spp. fed on conventional diets ad libitum. Yeasts were present in comparatively large numbers in the monkey, pig, rat, mouse, hamster, and guineapig, and in small numbers or not at all in...

THOUGH many animals can become accustomed to the presence of fire, man alone has learned to produce, to maintain and to control it. However, this achievement is not peculiar to Homo sapiens. Fire was known also to Homo neanderthalensis and Pithecanthropus pekinensis1. From the study of fire-myths and the cultures of primitive races, it is usually presumed that fire was first obtained from such natural sources as volcanoes, bush fires, lightning, sparks struck from stones, or dry branches rubbing together in the wind2–5. Myths, however, are not necessarily reliable as guides to the distant past, while the reaction of animals, even of modern man, to volcanoes and forest fires is one of terror. Even when fear has been mastered, the practical difficulties of obtaining fire from these sources are still immense. Natural production of fire by friction or percussion is too rare to be readily observed by members of a small and scattered population.

Insulin and saline were injected into the right and left femoral arteries respectively of 19 alloxan-diabetes-mellitus dogs for 1 to 28 weeks. A significant increase of artery tissue cholesterol and total fatty acids was found on comparing the insulin-administered right leg with the saline-administered left leg. Similarly, a significant increase of total fatty acids in muscle was found on comparing the right with the left leg of the alloxan-diabetes mellitus dogs. No significant differences were observed in the normal animals when the insulin-injected side was compared with the noninjected.

This article is a survey of the history of nutrition education, including nutrition classes and school programs, in the United States.