Increases in Dietary Cholesterol Are Associated With Modest Increases in Both LDL and HDL Cholesterol in Healthy Young Women

Abstract

We studied the effects of dietary cholesterol intake on lipid and lipoprotein levels in healthy young women (n = 13) who were otherwise eating an American Heart Association (AHA) diet. The study used a randomized, three-way crossover design to determine the effects of 0, 1, or 3 eggs added per day (dietary cholesterol range, 108 to 667 mg/d). Each of the three diets was eaten for 8 weeks, with a washout period between diets. Three fasting blood samples were obtained during the last 3 weeks of each diet period to observe changes in fasting plasma lipid levels associated with the menstrual cycle. We also obtained blood just before and 4 and 8 hours after the subjects ingested a standard high-fat formula. During the menstrual cycle, total cholesterol and LDL cholesterol levels fell by 0.051 mmol/L (1.99 mg/dL) and 0.064 mmol/L (2.48 mg/dL) per week, respectively. HDL cholesterol concentrations increased by 0.060 mmol/L (2.3 mg/dL) per week during the first half of the cycle and then fell by 0.050 mmol/L (1.94 mg/dL) per week during the second half. Therefore, all statistical analyses were performed on values adjusted to midcycle. Total fasting cholesterol concentrations increased by 0.073 mmol/L (2.81 mg/dL) per 100 mg dietary cholesterol added to the diet per day (P=.001). LDL cholesterol increased by 0.054 mmol/ L (2.08 mg/dL) per 100 mg/d dietary cholesterol (P=.003); this accounted for about 75% of the rise in total cholesterol. HDL cholesterol concentrations increased by 0.015 mmol/L (0.57 mg/dL) per 100 mg/d dietary cholesterol (P<.04). There was a wide range of responses among the women. Plasma apoB levels increased significantly, 0.93 mg/dL per 100 mg/d dietary cholesterol (P=. 025), whereas apoA-I levels tended to rise (1.35 mg/dL per 100 mg/d, P=.056). Increases in dietary cholesterol did not produce any observable effects on fasting plasma cholesteryl ester transfer protein levels and had no effect on the response to a standard high-fat formula. Although menstrual-cycle changes in plasma total, LDL, and HDL cholesterol levels were observed, the effects of the diets were similar in the follicular and luteal phases of the menstrual cycle. Additionally, despite changes associated with the menstrual cycle, within-subject variation in plasma total cholesterol was actually smaller in this study than in our study of young men. Keywords plasma lipids; dietary fatty acids; menstrual cycle; lipoproteinsIn a recent study in healthy young men of the effects of increases in dietary cholesterol on plasma lipids and lipoproteins, we demonstrated that plasma total cholesterol levels © 1995 American Heart Association, Inc. Women were not included in our study or in the studies of several others. 2-4 Zanni et al 6 studied the effects of dietary cholesterol in only women, but in that investigation diets were fed for only 15 days. 6 Both men and women have been included in several more recent studies that focused on the effects of dietary cholesterol, 7-9 but only in one 9 were the data analyzed by the sex of the su...

Sex differences in lipoprotein metabolism and dietary response: Basis in hormonal differences and implications for cardiovascular disease

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Predictors of postprandial triacylglycerol response in children: the Columbia University Biomarkers Study

“…In adults, delayed postprandial clearance is associated with higher fasting triacylglycerol concentrations (6). Fasting triacylglycerol concentrations are generally lower in children than in adults (28,30). In view of the evidence for a role of delayed postprandial clearance as a risk factor for IHD, the question arises whether delayed postprandial clearance is also present at an early age in children, and if so, which metabolic characteristics predict abnormal clearance in children.…”

“…LDL-cholesterol concentrations were determined by using the Friedewald equation (27). Plasma retinyl palmitate concentrations were determined by reversed-phase HPLC essentially as described previously (10,28). Apo E genotyping was performed by using genomic DNA as described by Hixson and Vernier (29).…”

Thematic review series: Patient-Oriented Research. Dietary fat, carbohydrate, and protein: effects on plasma lipoprotein patterns

“…Estimating the absolute effect of dietary cholesterol on plasma lipoprotein concentrations has been difficult because of the high degree of variability in response among individuals (89). Nonetheless, in carefully controlled studies performed in healthy young males and females, it was demonstrated that for every additional 100 mg of dietary cholesterol, fasting plasma total cholesterol concentrations increased by 1.47 and 0.73 mg/dl, respectively, with parallel increases in LDL cholesterol and apoprotein B concentrations (90,91). Increased levels of the cholesteryl ester transfer protein were observed at the highest levels of dietary cholesterol in males but not females.…”