Beware of Soya Bean
I am disturbed after reading the article, "Soya bean cuts breast cancer risk" in the Straits Times of 12 August 2008.
The study by the National University of Singapore (NUS), the University of Southern California and the University of Minnesota found that eating a serving of soya bean curd or drinking a glass of soya milk every day reduces the risk of breast cancer for Chinese women in Singapore. Women who ate more soy products were 18 percent less likely than those from the other group to develop breast cancer.
I learned that scientists began studying the role that isoflavones play in reducing the risk of breast cancer in the 1960s. Some researchers suggest they may act as anti-estrogens and reduce breast cancer growth, while others suggest their estrogenic activity could cause breast cancer to grow faster. Until this issue is resolved, many medical oncologists and oncology nutritionists in the United States recommend that people who take tamoxifen or people with estrogen-sensitive breast tumours should avoid the addition of large amounts of soy to their diets.
Being a layperson, I hoped for feedback from doctors or scientists who would come forward to share the same concern. Indeed, I am glad to read the online letter published on August 18, "Health benefits of soya beans" by Dr Yik Keng Yeong. It was a pity that the Straits Times did not publish Dr Yik's letter in print. Hence it failed to reach out to more readers.
I hope the public will become more discerning when presented with controversial findings on the health benefits of soya bean and soy products, and make an informed decision on what is good for them. Hence I wrote to the ST Forum but they rejected my letter owing to the lack of editorial space.
We should take cue from the latest findings on trans fat, which has proven trans fat is bad for health and now carry a health warning label on products with trans fat.
To read Dr Yik's letter in ST Forum Online, please click here
In the event that ST Forum Online removes the webpage, please read the following extract of Dr Yik's letter :
"It may now not be controversial to recommend soya bean in a normal woman's diet. Yet, in women with benign fibrocystic disease where oestrogens are also causative, is such a recommendation detrimental? How are we to recommend soya bean to women who don't have breast cancer but who are at higher risk of developing it, namely those with a family history, the childless, those with early puberty or late menopause? Am I to recommend them an advantageous glass of soya a day as the NUS researchers have suggested, or should I be more suspicious of the phytoestrogens in the soya and tell these women to be more circumspect? As for the unfortunate patients who have or have had breast cancer, is there rationale in recommending them soya, when in theory the phytoestrogens in them may be deleterious to their health and counteractive to the antioestrogen therapy they may be on? "
Posted on 22 August 2008
Update On 23 August 2008
ST Forum published NUS researchers reply online - please click here : Soy benefit: Researchers reply