A new study suggests there is no evidence that soy-based foods reduce the risk of uterine cancer.
Soy foods contain isoflavones, which is an estrogen derived from plants that has been shown to protect against cancer, HealthDay reported.
Researchers looked at 49,000 Japanese women who were given two surveys over a five-year period that outlined their "diet, lifestyle, medical history and food consumption of eight soy food items, including miso soup, tofu and soy milk," HealthDay reported
After the five year study 112 of the study subjects were diagnosed with uterine cancer, but no association was found between the consumption of soy and these diagnoses.
The researchers observed that women who consumed more soy-based food products also tended to eat more vegetables, had less health problems such as diabetes, and were less likely to consume tobacco or caffeine.
There was still no association between soy consumption and a reduced risk of uterine cancer even after the researchers adjusted for factors such as "age, alcohol consumption, smoking, BMI, menopausal status, coffee intake and number of deliveries," a Wiley news release reported.
"Our study found that intake of soy and isoflavones were not associated with the risk of endometrial cancer," study co-author Doctor Motoki Iwasaki, of the National Cancer Center in Tokyo, said in the news release.
"This large population-based study found no evidence of a protective association of soy food or isoflavone intake and previous studies have been inconsistent," John Thorp, BJOG Deputy-Editor-in-Chief, said in the news release. "Confirmation of these results needs further investigation and larger more diverse studies."
The rate of uterine cancer is generally lower in Asian countries, but the rate has been increasing over the years. The consumption of soy also tends to be more prevalent in Asian countries.
"We need further studies with a greater number of cases to verify these findings and add to the research base," Iwasaki said.
