Low concentrations of total and LDL cholesterol are associated with minimal risk of atherosclerosis. Aerobic exercise has been similarly associated with a low risk of heart disease. The literature is inconclusive as to whether there is an association between total and LDL cholesterol and exercise. Further, previous work has, almost exclusively, examined male runners. Therefore, we examined 176 male and female cross-country skiers, participating in the National Master's Championships, for body composition, dietary habits, exercise habits, and serum lipid levels. Our results show markedly low concentrations of serum LDL cholesterol and total cholesterol, as well as the expected high concentrations of HDL cholesterol and low concentrations of triglycerides, in these lean skiers. Their diets contained 30% fat, and they exercised 9 h weekly. Although it is difficult to separate the effects of diet, leanness, and exercise on the lipid profile, it is apparent that the lifestyle led by these people is associated with a lipid profile that confers an extremely low risk of atherosclerotic disease.