Nutrient intake and gastric cancer in Mexico.

In contrast to the decreasing trends observed in most countries, gastric-cancer mortality has remained at about the same level in Mexico throughout the last 40 years. As part of a study carried out in the metropolitan area of Mexico City, an assessment of nutrient intake and gastric cancer is presented here. The study population comprised 220 cases of gastric cancer and 752 population-based controls. Our results showed 70 to 80% reduction in the risk of developing this tumor, associated with the intake of polyunsaturated fat, fiber and vitamin E; and this effect was independent of the histological type of the tumor (i.e., intestinal or diffuse). On the other hand, an increased risk of gastric cancer was related to the consumption of saturated fat (OR(Q4vs.Q1) = 4.37, 95% CI 1.89-10.12) and, cholesterol (OR(Q4vs.Q1) = 2.39, 95% CI 1.23-4.64), but such effects were restricted to the intestinal type of gastric cancer. In the whole study population, mono-unsaturated fat intake increased the risk for gastric cancer, and a marginally significant increasing trend was observed for protein consumption. The findings from this study add information about the role of specific nutrients in the etiology of gastric cancer.

Dietary factors and the risk of gastric cancer in Mexico City.

Dietary factors play an important role in gastric cancer risk but have not been investigated extensively in Mexico. The authors conducted a population-based case-control study of gastric cancer in the Mexico City, Mexico, metropolitan area in 1989-1990. A total of 220 patients with histologically confirmed gastric adenocarcinomas were interviewed. Controls were an age-stratified random sample of residents of the Mexico City metropolitan area. The dietary questionnaire was a 70-item semiquantitative food frequency adapted for the Mexican diet. Odds ratios were calculated for quartiles of consumption of food groups and were adjusted for age, gender, calories, chili pepper intake, cigarette smoking, socioeconomic status, added salt, and history of peptic ulcer disease. There was approximately a threefold increased risk of gastric cancer for frequent consumption (highest quartile) of both fresh meat (odds ratio (OR) = 3.1) and processed meat (OR = 3.2). Odds ratios were also significantly elevated for frequent consumption of dairy products (OR = 2.7) and fish (OR = 2.2). The authors observed a decreasing gradient of risk with increasing frequency of vegetable consumption due to a significant inverse trend for the yellow and orange vegetables. High intake of citrus fruits showed a slight inverse association. Consumption of salty snacks more than twice per month was associated with an 80 percent increased risk, and there was a significant positive trend. These findings are consistent with many studies around the world that indicate important roles for salt, processed meats, and vegetable consumption in gastric cancer risk.