Eating soy products such as tofu and soybean paste can decrease the risk of gastric cancer, research showed Wednesday.

A joint research team led by Kang Dae-hee and Shin Woo-kyoung, professors at Seoul National University’s Department of Preventive Medicine, showed that higher consumption of soy or bean-based products may be linked to a reduced risk of developing stomach cancer. The finding was based on research conducted over an average of nine years with 139,267 participants -- 46,953 males and 92,314 females -- who participated in the Health Examinees (HEXA) study between 2004 and 2013.

The research team also tried to closely examine the effects of consuming soybeans, soybean paste and tofu on gastric cancer, with some 767 respondents who had cancer and those who didn’t.

Soybean paste, also known as South Korea’s seasoning paste, is made by fermenting cooked soybeans with salt over several months. Tofu is made from soybeans ground in water, which are heated and later coagulated with calcium or magnesium salt minerals.

The results showed that men who consumed tofu at least twice a week had a 37 percent reduced risk of getting stomach cancer compared to men who didn't eat much tofu.

Men who consumed tofu and had a body mass index below 23 kilograms per square meter, or those who weighed below the male average, were linked to a lower risk of developing stomach cancer, while such correlations were not observed in obese or overweight men, according to the research group.

The research team also found that genistein, a compound found in soy products, and isoflavone, a type of estrogen-like substance produced by plants like the soy plant, may reduce the risk of gastric cancer.

“Soybean paste made in Korea is considered to have a better effect on preventing gastric cancer as more physiologically active substances are produced during the long fermentation process,” said Prof. Shin.

The research was also published in the latest edition of the European Journal of Nutrition, which publishes original papers, reviews and short communications in the nutritional sciences.