Is tofu safe? Prostate Cancer UK says more research is needed to confirm soya link

Prostate Cancer UK said more research was needed to confirm the link between prostate cancer and tofu. 

A US study, published on 8 November in the International Journal of Cancer, claimed men eating foods rich in isoflavones could be at risk of developing prostate cancer - the UK’s most common cancer in males. 

Isoflavones are compounds which are derived from plants and are found mostly in soy flour, but are also found in soybeans, tofu and miso.

Prostate Cancer UK director Dr Iain Frame told “This study suggests a potential link between foods high in isoflavones such as soyabeans and tofu and increased risk of advanced prostate cancer, however, there is currently not enough concrete evidence to say whether this is actually the case.

“Much more research is needed to measure the actual intake of isoflavones in people with varied eating habits.”

The study was published during Movember - the annual month-long charity campaign to raise awareness for men’s health.

Dr Jianjun Zhang, lead author of the research from Fairbanks School of Public Health at Indiana University in Indianapolis, writes in the study abstract: “Prostate cancer is a major cancer in Western countries, and its incidence rate has been remarkably increasing in Asian countries during the last several decades. 

“Age, ethnicity and family history are the only established, but non-modifiable, risk factors for this malignancy.”

The researchers compared the number of prostate cancer cases in more than 27,000 men over an 11 year period. The cancer was found in 2,598 of them, with 287 being advanced cases.

Men taking part in the study were asked to write down everything they ate over the period. From this, scientists reported they found isoflavones to be linked to a higher risk of developing prostate cancer.

“Our study offers novel evidence that dietary intake of isoflavones has different effects on advanced and non-advanced prostate cancer,” said Zhang.

“This observation is important for understanding the ethology and prevention of prostate cancer, but needs to be confirmed in more epidemiological studies among populations with diverse dietary habits.”

Currently there are very few establish risk factors for prostate cancer, and more research was needed, according to oncologist Dr Jiri Kubes, a prostate cancer specialist from the Proton Therapy Center in Prague.

“It’s therefore vital that men are aware of the early warning signs, and are visiting their GPs as soon as they suspect something may be wrong. Often, prostate cancer can be present without any warning signs.”

Meanwhile, last week it was revealed that soya foods could help to suppress the development of breast cancer.

There were 46,690 new cases of prostate cancer diagnosed in 2014, according to Cancer Research UK.

More than 11,000 people died from the disease in the same year. Symptoms include burning, or pain when urinating, frequent urinating at night, finding blood in urine and loss of bladder control.

A healthy diet and regular exercise could help to lower the risk of developing prostate cancer, said Prostate Cancer UK.