The Norwegian diet during the last hundred years in relation to coronary heart disease.

OBJECTIVE

The influence of dietary changes on serum cholesterol and CHD during the last century in Norway has been evaluated.

DESIGN

Data on food consumption are based on national food supply and household consumption surveys. To be able to calculate comparable series of the dietary content of energy, fat, saturated, monounsaturated and polyunsaturated fatty acids and dietary cholesterol, we compiled food composition data covering this century. The dietary effect on serum cholesterol was estimated by Keys equation.

RESULTS

Changes in dietary lipids precede the increase and the decrease in mortality of CHD. The estimated serum cholesterol level in the population increased by approximately 1 mmol/l during 1900-1960, and decreased by approximately 0.6 mmol/l during 1960-1992. These changes correspond to a 60% increase and a 30% decrease in risk for CHD. However, the observed change in mortality of CHD was greater. During 1951-1955 and 1971-1975 it increased by 120% in men and 80% in women aged 50-59 years and during 1971-1975 and 1991-1993 it decreased by 43% and 29%, respectively.

CONCLUSIONS

Change in dietary lipids have the potential to explain a great deal of the changes in mortality of CHD in Norway during this century. A reduced consumption of boiled coffee and an increase in the consumption of antioxidants may also have contributed to the reduced mortality of CHD the last 20 years.