The effects of weight loss by exercise or by dieting on plasma high-density lipoprotein (HDL) levels in men with low, intermediate, and normal-to-high HDL at baseline

To assess whether baseline plasma high-density lipoprotein (HDL) cholesterol levels affected the HDL response to weight loss, we examined lipoprotein changes in overweight men aged 30 to 59 years who were randomized to lose weight by exercise training (primarily running, n = 46) or by caloric restriction (ie, dieting, n = 42) or to remain sedentary, nondieting controls (n = 42) in a 1-year study. In exercisers, absolute increases in HDL (mg/dL) were greatest in men with normal-to-high baseline HDL and least in men with low baseline HDL. Specifically, when divided into groups of low (≤ 37 mg/dL), intermediate (38 to 47 mg/dL), and normal-to-high HDL cholesterol (≥ 48 mg/dL) at baseline, the exercisers increased HDL cholesterol by 2.3 ± 1.9, 4.9 ± 1.1, and 7.0 ± 1.3 mg/dL, respectively; HDL 2 cholesterol by 0.8 ± 1.6, 2.3 ± 1.2, and 5.1 ± 1.3 mg/dL; and HDL 2 mass by 2.8 ± 5.1, 9.5 ± 8.9, and 31.7 ± 11.0 mg/dL. Relative increases in HDL cholesterol were more similar in the low (7.1% ± 6.1%), intermediate (12.4% ± 3.9%), and normal-to-high men (13.2% ± 4.0%). Regression analyses were performed to assess whether baseline HDL cholesterol was related to the amount of absolute HDL change per unit of weight loss. In exercisers, the increase in HDL 3 cholesterol concentrations was significantly greater in men with low HDL than in those with normal-to-high HDL at entry (2.0 ± 0.8 v 0.2 ± 0.8 mg/dL per kg/m 2 lost). In contrast, the increase in HDL 2 cholesterol was nearly four times greater in men with normal-to-high HDL than in those with low HDL at entry (3.7 ± 0.7 v 1.0 ± 0.7 mg/dL per kg/m 2 lost). In dieters, weight loss significantly increased HDL cholesterol, HDL 2 cholesterol, and HDL 2 mass after 1 year, but the absolute increases were unrelated to baseline HDL cholesterol level. Thus, exercise-induced weight loss but not diet-induced weight loss affects HDL cholesterol concentrations in men differently depending on their entry level.