The authors used special tests (Doppler echocardiography spectral velocity tracings) to estimate coronary flow reserve. Five men had this test before and after a high-fat liquid meal and before and after a low-fat liquid meal. Ten additional men had the test only before and after the high-fat liquid meal. The high-fat meal contained 1200 calories, 100 grams of fat, 50 grams of saturated fat, and 300 milligrams of cholesterol. The low-fat meal contained 1200 calories, 10 grams of fat, 2 grams of saturated fat, and 6 milligrams of cholesterol. All 15 men had blood drawn after the high-fat meal to measure levels of fatty substances (triglycerides).