University of Minnesota

Ragnar Nicolaysen, MD

1902 — 1986

Ragnar Nicolaysen was one of the early proponents of the diet-cholesterol-atherosclerosis hypothesis in Scandinavia where he was Director of the Institute for Nutrition Research at the University of Oslo from 1940 to1973. His early research covered mineral and vitamin metabolism, particularly calcium and vitamin D, but in the 1950s he focused on the relationship of dietary fats and plasma lipids to atherosclerosis as published in Scandinavian medical journals (1,2). He also conducted experiments on the effects of unsaturated fatty acid consumption on plasma lipids (3) and developed a rapid and sensitive method for the determination of serum total cholesterol (4).

In 1958 he launched the first prospective epidemiological study on coronary heart disease and its risk factors in Norway, comprising an occupational cohort of men aged 40 – 49 in which serum cholesterol, blood pressure, and weight/height index (but not smoking status) were measured(5). Together with Knut Westlund, another Norwegian pioneer in this field, he conducted a 10-year follow-up study of 3,751 men from the original cohort, during which 213 men had their first myocardial infarction. Both serum cholesterol and blood pressure showed a strong relationship with the risk of myocardial infarction. The impact of cholesterol on the risk was similar to that observed in the 12-year follow-up of the Framingham Study, but that of blood pressure was stronger in Oslo.

From his initiative, the role of diet in cardiovascular disease got an early and strong emphasis in Scandinavian public recommendations about diet and health. (KP)


1) Nicolaysen, R. Arteriosclerosis and cholesterol. 1951. Nordisk Medisin 45:738

2) Nicolaysen, R. Diet and arteriosclerosis. 1952. Nordisk Medisin 48:1678.

3) Hauge, J.G. and Nicolaysen, R. 1959. The serum cholesterol depressive effect of linoleic , linolenic acids and cod-liver oil in experimental hypercholesterolaemic rats. Acta Physiologica Scandinavica 45:26-30.

4) Hauge, J.G. and Nicolaysen, R. 1959. A rapid and sensitive method for the determination of serum cholesterol. Acta Physiologica Scandinavica 43:359-364.

5) Berge, A. and Nicolaysen, R. 1963. Serum cholesterol in middle-aged men working in Oslo. Scandinavian Journal of Clinical and Laboratory Investigation 15;284-290.

6) Westlund, K. and Nicolaysen, R. 1972. Ten-year mortality and morbidity related to serum cholesterol. A follow-up of 3,751 men aged 40-49. Scandinavian Journal of Clinical and Laboratory Investigation 127:1 -24.