The Serum Lipids in Men Receiving High Cholesterol and Cholesterol-Free Diets*

In a previous study we found that dietary cho- lesterol provided in the form of egg yolk had a great effect upon the serum cholesterol and phos- pholipid levels in healthy human subjects (2). This effect was obtained with the use of high cholesterol and cholesterol-free diets which were bal- anced closely in the amounts of fat and in fatty acid composition. The range of cholesterol intake so tested was from 1,700 to 4,800 mg per day, amounts clearly above the usual daily American consumption of 500 to 1,000 mg. The present investigation was designed to examine the serum lipid responses of six men given dietary cholesterol as egg yolk in amounts compatible with usual dietary intakes. The effects of egg yolk cho- lesterol and crystalline cholesterol were also compared.