Consumption of processed and ultra-processed foods by patients with stomach adenocarcinoma: a multicentric case-control study in the Amazon and southeast regions of Brazil.

Purpose: There is limited information about the dietary habits associated with stomach adenocarcinoma in the Brazilian population, so our purpose is to analyze the consumption of processed and ultra-processed foods by patients with stomach adenocarcinoma in Brazil.

Methods: A multicentric hospital-based case-control study was conducted in São Paulo (southeastern region) and Belém (Amazon region) of Brazil with 1,045 individuals, both sexes, between 18 and 75 years old. In São Paulo, there were 214 cases with stomach adenocarcinoma and 150 controls patients submitted to stomach endoscopy named as Group I (without any pre-malignant gastric disease) and the Healthy Controls (Group 2) comprised 401 individuals matched by age and sex from the prevention unit at A.C .Camargo Cancer Center. In Belém, it has two groups one are cases 140 and second 140 hospital controls, recruited in outpatient clinics. Lifestyle and food frequency questionnaires (FFQ) were administered in cases and controls in both places. Univariate and multivariable binomial logistic regression analyses were performed.

Results: In São Paulo, cases reported two times greater consumption of processed meat (adjusted OR 2.56, 95% CI 1.32-4.96) and of sweets (≥ 80 g/day) than Group 1 (endoscopic controls) (adjusted OR 2.25, 95% CI 1.21-4.18). Compared with Group 2, processed food consumption (≥ 44 g/day) as well as ≥ 44 g/day of salted bread increased the odds of having stomach adenocarcinoma (adjusted OR 2.96, 95% CI 1.82-4.81 and adjusted OR 2.03, 95% CI 1.30-3.18), respectively. In Belém, individuals who reported consuming ≥ 166 g/day of fried and roasted meat and fish were more likely to have stomach adenocarcinoma (adjusted OR 2.21, 95% CI 1.13-4.30).

Conclusions: In both cities, consumption of processed and ultra-processed foods, especially salted bread, yellow cheese, fried and roasted meats, fish fried, processed meat, and sweets, was independently associated with the chance of having stomach adenocarcinoma.