9 July 1998

Soy Beans And Exercise Explain Low Cholesterol Levels In Japan

If you're overweight, have a poor diet and don't get much exercise then you probably have high cholesterol, and your long-term health barometer is not looking good.

This Sherlock Holmesian decuction is the result of an Australian study of the differences in high-density lipoprotein (the "good cholesterol") levels in American, Australian and Japanese children. Conducted by Terry Dwyer of the Menzies Centre for Population Health Research at the University of Tasmania, the study involved more than 20 000 children. Death from coronary artery disease in men is five times higher in Australia and the US than it is in Japan, even though the percentage of Japanese men who smoke is much higher. Couple this with the fact that the Japanese diet has undergone rapid westernisation over the last thirty years and you have an interesting scientific question - why do the Japanese have more good HDL cholesterol and less of the bad stuff than their Australian and American counterparts?

Part of the answer lies in what they eat, particularly soybean products like tofu - a favourite among children and adults alike. Tofu contains phytoestrogens, which if consumed in significant amounts might be responsible for higher HDL. The behaviour of phytoestrogens in the body resembles that of human hormones.

The study also shows that Japanese children consume almost 20 percent less fat than their Australian and American counterparts. They were also more likely to be physically active, with organized sporting activities forming an essential part of most school timetables.