Higher dietary total antioxidant capacity is inversely associated with Helicobacter pylori infection among adults: A case-control study.

Introduction: Antioxidants appear to hinder the actions of Helicobacter pylori (H. pylori). The aim of this research was to evaluate the association between dietary total antioxidant capacity (DTAC) and H. pylori infection.

Methods: A case-control study was carried out among 200 patients with  H. pylori infection and 402 healthy subjects (18-55 years). Dietary data were collected using a validated 168-item quantitative food frequency questionnaire. DTAC was calculated based on the oxygen radical absorbance capacity of each food (except for coffee) reported by the US Department of Agriculture.

Results: Compared with participants in the lowest tertile of DTAC, those in the highest tertile had a significantly lower odds ratio (OR) in the crude model (OR, 0.29; 95% CI, 0.14-0.61; p for trend = 0.001), model 1 (adjustment for age and sex) (OR, 0.37; 95% CI, 0.24-0.58; p for trend < 0.001), and model 2 (adjustment for model 1 plus body mass index, waist circumference, physical activity, smoking, dietary intake of energy and fat) (OR, 0.20; 95% CI, 0.10-0.40; p for trend ≤ 0.001).

Conclusions: A high DTAC is associated with a reduced risk of H. pylori infection in adults. Further studies are mandatory to elucidate the mechanisms and a dose-effect relationship.