Biochemical aspects of a study of 100 obese white subjects.

The effect of a 7 100 kilojoule diet (50% of the energy derived from carbohydrate, mainly unrefined, 30% from fat, mainly unsaturated, and 20% from protein) on 100 overweight subjects was investigated. It was found that 45% of subjects did not complete the study, 9% continued with the study but did not lose weight, 25% lost weight moderately well and 21% responded very well and lost a mean of 15,9 kg over a 6-9 month period. Very little indication of water retention was found. The following biochemical changes occurred during the study period: 1. There was a marked improvement in the glucose tolerance of the groups that lost weight effectively. 2. This improvement in glucose tolerance was associated with a very marked decrease in the secretion of immuno-reactive insulin. 3. The tendency for serum cholesterol and triglyceride levels to decrease during the study was also evidenced in the changes which occurred in the lipoprotein electrophoresis patterns. Stepwise discriminant analysis performed on biochemical, clinical and psychological data failed to provide a practical means of discriminating in advance between the likely response of subjects to this dietary therapy with acceptable accuracy.