News article

No evidence that soy food protects against endometrial cancer, study finds

Posted:  Monday, June 23, 2014

Endometrial cancer is the cancer of the inner layer of tissues that lines the uterus. Cancer, in this layer constitutes for 90 percent of the uterine cancers. More than 49,560 cases are reported of women over the age of 55 suffering from endometrial cancer.

A recent study has found no correlation between the consumption of soy products and the protection it provides from endometrial cancer.

The presence of isoflavones, a plant derived of estrogen in Soy foods, has been suggested to be protective against cancer. However, previous studies have produced inconsistent findings regarding the effect of soy foods on endometrial cancer.

Soy is one of the exclusive sources of isoflavones. Though some researchers have emphasised on its potential cancer protective properties, there have been contradictory studies that have yielded inconsistent results linking the two together.

Researchers aimed to determine whether the consumption isoflavones had protective properties. A survey was conducted to determine the consumption of 8 soy foods including miso soup, tofu and soymilk. Other sources of isoflavones were also evaluated such as of genistein and daidzein. In spite of the intake of Soy foods, 112 women were diagnosed with endometrial cancer.

The women in the older age group, were noted to have consumed more isoflavones also consumed more fruit and vegetables and also were less likely to be smokers, drinkers and regular coffee drinkers with a history of diabetes.

The studied predominantly looked at the intake of tofu, miso soup and soy food. After examination of the Soy foods, they weren’t able to find a link between the soy and endometrial cancer. No correlation was found between the high intake of soy foods or isoflavones and the risks of endometrial cancer. Age, alcohol consumption, smoking BMI, menopausal state and coffee intake were taken into consideration during the study.

Dr Motoki Iwasaki, Epidemiology Division, Epidemiology and Prevention Group, Research Centre for Cancer Prevention and Screening, National Cancer Center, Tokyo, Japan and co-author said:

"Our study found that intake of soy and isoflavones were not associated with the risk of endometrial cancer.

"Although the incidence of endometrial cancer is much lower in Asian countries, the incidence rate has been increasing. We also know that the consumption of soy foods among Japanese people is very high.

"We need further studies with a greater number of cases to verify these findings and add to the research base."

John Thorp, BJOG Deputy-Editor-in-Chief, said:

"This large population-based study found no evidence of a protective association of soy food or isoflavone intake and previous studies have been inconsistent.

"Confirmation of these results needs further investigation and larger more diverse studies."

Patients who suffer from endometrial cancer show symptoms such as unusual vaginal bleeding, spotting or discharge (also non bloody discharge), along with pelvic pain, a tumour growth and weight loss. Although, these symptoms can be associated with other illnesses besides cancer, but it is important to get checked by doctor, even if you don’t have a family history of cancer.