ELEVATED PLASMA LOW-DENSITY-LIPOPROTEIN AND HIGH-DENSITY-LIPOPROTEIN CHOLESTEROL LEVELS IN AMENORRHEIC ATHLETES - EFFECTS OF ENDOGENOUS HORMONE STATUS AND NUTRIENT INTAKE

To determine the interactive effects of hormones, exercise, and diet o n plasma lipids and lipoproteins, serum estrogen and progesterone leve ls, nutrient intake, and plasma lipid, lipoprotein, and apolipoprotein concentrations were measured in 24 hypoestrogenic amenorrheic and 44 eumenorrheic female athletes. When compared to eumenorrheic athletes, amenorrheic athletes had higher levels of plasma cholesterol (5.47 +/- 0.17 vs. 4.84 +/- 0.12 mmol/L, P = 0.003), triglyceride (0.75 +/- 0.0 6 vs. 0.61 +/- 0.03 mmol/L, P = 0.046), low-density lipoprotein (LDL; 3.16 +/- 0.15 vs. 2.81 +/- 0.09 mmol/L, P = 0.037), high-density lipop rotein (HDL; 1.95 +/- 0.07 vs. 1.73 +/- 0.05 mmol/L, P = 0.007), and H DL(2) (0.84 +/- 0.06 vs. 0.68 +/- 0.04 mmol/L, P = 0.02) cholesterol. Plasma LDL/HDL cholesterol ratios, very low-density lipoprotein and HD L(3) cholesterol, and apolipoprotein A-I and A-II levels were similar in the two groups. Amenorrheic athletes consumed less fat than eumenor rheic subjects (52 +/- 5 vs. 75 +/- 3 g/day, P = 0.02), but similar am ounts of calories, cholesterol, protein, carbohydrate, and ethanol. HD L cholesterol levels in amenorrheic subjects correlated positively wit h the percent of dietary calories from fat (r = 0.42, n = 23, P = 0.04 5) but negatively with the percent from protein (r = -0.49, n = 23, P = 0.017). Thus, exercise-induced amenorrhea may adversely affect cardi ovascular risk by increasing plasma LDL and total cholesterol. However , cardioprotective elevations in plasma HDL and HDL(2) cholesterol may neutralize the risk of cardiovascular disease in amenorrheic athletes .