Variable effects of weight loss on serum lipids and lipoproteins in obese patients.

After a 500 calorie diet and 6 months of low fat, maintenance diet, weight, serum lipid, and lipoprotein levels were compared to baseline in 46 obese patients. Mean weight decreased by 25.9 percent (29.2 kg). Mean total (TC) and low density lipoprotein cholesterol (LDL-C), and triglycerides (TG) decreased by 5.5 percent (12.1 mg/dl), 11 percent (15.5 mg/dl) and 23.6 percent (34.5 mg/dl); mean high density lipoprotein cholesterol (HDL-C) increased by 20.6 percent (10.3 mg/dl) and TC/HDL-C decreased by 25 percent (1.2), P less than 0.01. Females and males had equal increases in HDL-C. The decrease in TG and TC in patients who continued to lose 4.2 kg during the 6 month maintenance period was significantly greater than in those who regained 7.8 kg (P less than 0.015). Greater changes in HDL-C and TC/HDL-C occurred in younger individuals (r = -0.35 and r = -0.37); in those with more abnormal initial values (r = -0.60, r = 0.64); and for HDL-C, a larger increase occurred in those with greater weight loss (r = 0.32; P less than 0.04).