Nutrition and ageing at the population level.

There are important differences in the expectation of life between countries where infectious diseases were for the greater part eradicated and other countries. Whereas in Japan one man in the age class of 55 to 64 years dies, about three men of the same age die in Hungary and 3,7 men in the Russian Federation. The death rate is significantly lower in all countries for women than for men. A highly significant linear relation exists between the log mortality owing to all causes and age. The slope of this equation is considered as the expression of the ageing of a population, to which it is inversely proportional. This is explained by the fact that the human race possesses a maximal age that differs very little from one country to another. This can be proved mathematically. Significant relations exist as well between the slope as between the intercept of the equation of log mortality from all causes and of age, due to the consumption of saturated fat (the latter increases the mortality) or the proportions in the consumption of polyunsaturated and of saturated fat by different populations (P/S and U/S ratio's). There is also a very significant correlation between log total mortality for cancer and log age. After adjusting the intake of saturated fat, the differences of cancer-mortality between the countries are no longer significant in men and the significance decreases strongly in women. Our conclusion is that food is the most important determinant of life expectancy between and within the populations.