In several experiments it was shown that a deficiency of vitamin B(1) in the diet increased the resistance of mice to the Lansing strain of poliomyelitis. The source of the virus was a suspension of infected mouse brain in saline, which was injected intracerebrally. Both the mortality rate and the incidence of paralysis were lower in the deficient animals than in the normally fed controls. The protection was more pronounced with respect to paralysis than with respect to the number of deaths.
Experiments were done to determine whether undernutrition with consequent loss of weight or failure to gain weight inhibited the development or promoted the regression of the aortic lesions of experimental cholesterol atherosclerosis in the rabbit. The experiments were conducted in such a way as to determine whether undernourished and adequately nourished rabbits fed the same daily doses of cholesterol would manifest different degrees of atherosclerosis at the end of an experiment.
Lipogenesis and the metabolism of sn-glycerol-3-phosphate were studied in 23 fat biopsies from eight grossly obese patients. The first biopsy was obtained after a minimum of 12 days on a 3500 cal diet, the second biopsy after 2 wk on a 900 cal diet, and the third biopsy after an additional 2 wk on 900 cal supplemented with thiiodothyronine, 250 mug/day.Oxygen consumption and respiratory quotient declined during caloric restriction.
The body weight of rats was reduced by exercise or by restriction of food intake over a period of 18 wk. Body composition was studied to determine if exercise protects against the loss of lean tissue that can occur as a result of a negative caloric balance. Rats weighing 706 +/-14 g were divided into four groups matched for weight. A baseline group was killed at the beginning of the study. An exercising group, fed ad lib., was subjected to a program of swimming. A sedentary, free-eating group was provided with food ad lib.
Canadian Family Physician Médecin De Famille Canadien
A weight gain of approximately 25 lb during pregnancy is compatible with an optimal outcome. The average gravida requires 2,200 kcal per day to meet the needs of mother and fetus. There is no good evidence that caloric restriction has any effect on the incidence, development or treatment of toxemia. Routine dietary salt restriction or use of diuretics does not alter the incidence of toxemia and plays a minor role in treatment. During the second and third trimesters, pregnant women should have a supplement of 30 to 60 mg of elemental iron per day.
Six patients with hyperphagia (ingestion of 5-11 000 Kcals/day) associated with severe malabsorption and steatorrhoea are described. The cause of the malabsorption was coeliac disease in three patients, Crohn's disease with ileal resection in two, and carcinoma of the pancreas in one patient. There was no evidence of neurological or endocrine disease (apart from mild diabetes mellitus in the patient with carcinoma of the pancreas) but three patients suffered from severe depression.
The effects of obesity and caloric intake on biliary lipid metabolism were investigated in a series of related studies. The degree of saturation of gallbladder bile with cholesterol was found to be significantly higher in a group of 23 obese healthy subjects than in a group of 23 nonobese controls matched for age, sex, and race. Bile was also significantly more saturated in 11 obese subjects before than after weight reduction.
The effect of a 4-week diet regulation on non-obese, adul-onset diabetics was studied. The diet, which was prescribed for them, was composed of 60% carbohydrate, 15-20% protein and 20-25% fat. The total caloric intake was restricted to 30, 35 and 40 Cal/kg ideal body weight depending on their physical activity. In the group whose calculated diet showed over 10% reduction in total caloric intake and carbohydrate intake, fasting glucose was decreased and glucose tolerance was improved significantly after the 4-week dietary therapy.
Current awareness of the importance of environmental factors such as diet in the etiology of human cancer has stimulated renewed interest in animal models for studying effects of diet on tumorigenesis. Diet can influence cancer in animals by affecting the initiation or subsequent preneoplastic stage of tumorigenesis, but it has less effect on tumor growth. Caloric restriction has a general inhibitory influence on tumorigenesis. Dietary fat, on the other hand, tends to promote tumorigenesis, but only certain types of tumors, such as mammary tumors, are affected.
Increased physical activity consisting of jog-walking 2.5 miles and 1 hr of calisthenics/week was the primary focus of a 17-week weight reduction program in 22 obese (X = 40% body fat) women ages 30 to 52, many of whom had failed at previous attempts to lose weight by dieting alone. Regular exercise was also increased substantially on an individual basis. Caloric restriction was self-determined and was generally moderate, accounting for about 60% of the total mean energy deficit.