From The October 2001 Issue of Nutrition Science News

Dietary Cholesterol Intake May Not Matter

Dietary cholesterol does not significantly affect serum cholesterol levels in postmenopausal women, concludes a study conducted by G.M. Reaven, M.D., of the Department of Medicine at Stanford University in Palo Alto, Calif. The study included 65 postmenopausal women followed for 12 weeks at either Stanford University or the University of Alabama at Birmingham.

The women were supplied with all their food. Its cholesterol content was manipulated using egg and egg substitute combinations. All diets contained 30 percent of calories in fat. The women began with four weeks on the baseline diet of 113 mg cholesterol. After a four-week washout period, they spent four weeks consuming either 319 mg, 523 mg, or 941 mg cholesterol per day.

Total serum cholesterol in the group consuming 941 mg dietary cholesterol daily averaged 184 mg/dl compared with 176 mg/dl for those consuming only 319 mg cholesterol per day. Serum LDL levels were 113 mg/dl compared with 107 mg/dl in the same two groups. The differences between the groups were not significant.

The researchers expected an increase in dietary cholesterol to raise plasma cholesterol more in insulin-resistant women, so they divided the women into insulin-resistant and non-insulin-resistant groups. Despite the threefold difference in insulin effectiveness between the two groups, the insulin-resistant women did not have a significantly higher rise in serum cholesterol levels.

Researchers conclude that dietary cholesterol restriction is unnecessary for people with normal cholesterol levels—although cholesterol-rich foods are usually also high in saturated fat and total fat.

—Metabolism 2001 May;50(5):594-7.