Simultaneous feeding of dihydrocholesterol and cholesterol to rats significantly reduced the amount of cholesterol absorbed into the thoracic lymph. Hypercholesteremia and hyperphospholipemia developed in rats simultaneously fed cholesterol and cholic acid for 8 weeks. The addition of dihydrocholesterol to this diet also decreased the rate of development and magnitude of the hypercholesteremia, but had no apparent effect upon the rise of plasma phospholipids.