When it comes to health foods, it’s hard to find a product with a better reputation than soy. But suppose that soy – which is derived from soybeans was actually harmful to certain demographics? If a recent study is correct, men might have to think twice before consume soy-heavy products.

Plant Problems

Heavy consumption of soy could increase men’s risk of advanced prostate cancer; this was the conclusion of researchers the Fairbanks School of Public Health at Indiana University in Indianapolis. The team chose to publish their findings in the International Journal of Cancer in November 2016.

So what could possibly explain this surprising connection? According to the study authors, the answer lies in the presence of isoflavones in soy products. Isoflavones are compounds produced by plants; when ingested by humans, isoflavones affect the body in a way similar to that of estrogen.

For their report, the researchers examined the diets and medical histories of approximately 27,000 men, all of whom had agreed to take part in Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Over a period spanning more than a decade, nearly one-tenth of these men (2,598 participants) were diagnosed with prostate cancer. The advanced from of this condition was found in 287 subjects.

More Work to Do?

Food frequency questionnaires were distributed to each individual participant. After reviewing the men’s answers, the research team found that advanced prostate cancer posed a much greater threat to men with isoflavone-heavy diets. Curiously enough, there was no such association observed between isoflavones and the non-advanced form of this cancer.

The study’s senior author, Dr. Jianjun Zhang, believes that his team’s work provides important insight into the development of prostate cancer. “Our study offers novel evidence that dietary intake of isoflavones has different effects on advanced and non-advanced prostate cancer,” stated Zhang. “This observation is important for understanding the etiology and prevention of prostate cancer, but needs to be confirmed in more epidemiologic studies among populations with diverse dietary habits.”