Wednesday, August 13, 2008

Soya bean cuts breast cancer risk

Soya bean cuts breast cancer risk

Aug 13 2008
Lee Hui Chieh
The Straits Times

Study by NUS and two US universities showed that women who ate more soya were 18% less likely to contract it.

Soya bean, a perennial Asian staple, is not simply versatile, nutritious and tasty. Eating a serving of soya bean curd or drinking a glass of the milk every day also reduces the risk of breast cancer for Chinese women in Singapore, a study has found.

The study by the National University of Singapore (NUS), the University of Southern California and the University of Minnesota, tracked more than 34,000 Chinese women aged 45 to 74 for a decade. They were split into two groups based on the amount of soya proteins in their diet, usually from dishes like fried soya bean curd (“taukwa” and “taupok”), bean curd sheets and a dish of bean curd, vegetables and fish cakes called “yong tau foo”.

A survey of their diet showed that half of them had less than a standard 115g serving of soya bean curd, or a 240ml glass of soya bean milk, every day; the other half had more than that. The epidemiological study sought to find out how such dietary habits affected their health.

Over a decade, up to December 2005, 629 women developed breast cancer: 339 from the group which ate less soya, and 290 from the other one. Women who ate more soya were 18 per cent less likely than those from the other group to develop breast cancer. Said a researcher, Associate Professor Koh Woon Puay of NUS’ department of community, occupational and family medicine: “Our study shows that the amount of soya needed is not high, and is easily achievable in a typical Asian diet.”

Just one glass of soya milk a day was enough to achieve a protective effect after 10 years, the study suggested. Post-menopausal women, those with a higher body mass index and those who had consumed soya for longer experienced the greatest reductions in risk, it found.

The study results are similar to those of at least eight others conducted on Asians, including in Japan, which showed an average 12 per cent reduction in breast cancer risk for soya-eaters. Studies on Caucasian women have been inconclusive, possibly because of the low levels of soya involved. But Prof Koh also cautioned against eating too much soya, which could lead to conditions such as gout.

The study was published in the British Journal of Cancer last month, and presented at an NUS breast cancer symposium yesterday. It was done as part of the larger Singapore Chinese Health Study, a longitudinal study of conditions like osteoporosis and Parkinson’s disease.

That has US$10 million (S$14 million) in grants from the National Cancer Institute, one of the United States’ National Institutes of Health. Separately, NUS’ Centre for Molecular Epidemiology plans a large-scale, 10-year study of about 12,000 Chinese, Malay and Indian women, both with and without breast cancer, to find out how genetic and lifestyle factors interact to determine breast cancer risk.

The centre is now sourcing for the $5 to $7 million needed for the study, said its director, Professor Chia Kee Seng.

No comments: