July 8, 1964
Mann describes how dairy fat and meat were eaten by Masai leading to a paradox.
Cardiovascular Disease in the Masai
George V. Mann
"These studies, like those of SHAPER among the Samburu and of GSELL AND MAYER among the mountain Swiss show no support for the contention that a large intake of dairy fat and meat necessarily causes either hypercholesterolemia or coronary heart disease. Indeed, if such dietary habits are causes of hypercholesterolemia, atherosclerosis and clinical cardiovascular disease, one must invoke overriding protective mechanisms among the Masai. It cannot be a failure to reach the susceptible age. We should have found coronary heart disease among the 233 Masai men examined who were 30 years or over if the prevalence rate is near that of American men."
A field survey of 400 Masai men and additional women and children in Tanganyika indicates little or no clinical or chemical evidence for atherosclerosis. Despite a long continued diet of exclusively meat and milk the men have low levels of serum cholesterol and no evidence for arteriosclerotic heart disease. The reasons for this disagreement with the popular hypothesis relating animal fat intake to coronary disease are examined. The authors concede that some overriding protective mechanism such as freedom from emotional stress or abundance of physical exercise may be present. They favor the conclusion that diet fat is not responsible for coronary disease.