Changes of some lipid and lipid peroxidation characteristics in obese people as a result of a low energy diet.

In blood samples of 54 obese persons (13 men, 41 women) some lipid components, malondialdehyde (MDA), and the activities of free radical protecting enzymes superoxide-dismutase (SOD) and glutathione-peroxidase (GSHpx), were determined before and after a seven-day slimming diet of 2.1 MJ/day. Body weight, triglycerides, HDL-cholesterol, and HDL-3-cholesterol all decreased, total cholesterol increased after the seven days hospitalization. After continuing the slimming diet (5.0-6.3 MJ/day) at home, HDL-2-cholesterol increased and total cholesterol returned to the initial value after three months. MDA decreased in the groups of hyperlipoproteinemia II/a and II/b and also in the group with high cholesterol and triglyceride levels (above 5.7 and 2.7 mmol/l). Correlation coefficients refer to the dominant role of high TG in the intensity of lipid peroxidation. The activity of SOD fell after the slimming, independent of lipid parameters. GSHpx activity remained unchanged except a drop in the male participants having high cholesterol levels. The behavior of the free radical protecting enzymes needs further examination.