Men whose diet is rich in vegetables have a lower risk of developing distal gastric cancer - a common disease among Japanese - than men with a low vegetable intake, the National Cancer Center has found.
The institute analysed data from about 190,000 participants in four extensive longitudinal studies on links between lifestyle habits and cancer risks. The centre has carried out the studies since 1988.
The participants were divided into five groups according to volume of vegetable and fruit consumption, and the groups' stomach cancer risks were compared.
Tracked for an average of 11 years, 2,995 of the 190,000 participants in the studies suffered from gastric cancer. Cancer risk decreased the most in participants who ate the most vegetables and fruit.
Meanwhile, data from about 150,000 participants were analysed according to cancer locations. Of those, 258 people developed cancer in the upper one-third of the stomach, and 1,412 had cancer in the lower two-thirds of the stomach.
The risk of stomach cancer among men with the highest vegetable intake was 78 per cent that of the men with the lowest vegetable intake. No association between vegetable intake and distal cancer risk was seen among women, who tend to eat more vegetables than men.
"As infection with Helicobacter pylori has been found to increase the risk of distal gastric cancer, which is a common disease among Japanese, the antioxidative effects of vegetables are believed to prevent Helicobacter pylori from damaging cells," said Taichi Shimazu, head of the institute's Research Center for Cancer Prevention and Screening.