People who eat a balanced diet with sufficient antioxidants from fruits and vegetables may face reduced risks for Heliobacter pylori infections, according to a new report.
In particular, patients with an H. pylori infection were more likely to score lower on the Dietary Antioxidant Index (DAI), which was created to consider a diet’s entire antioxidant profile.
“Available evidence indicates that diet has an important role in developing H. pylori infection. Therefore, protective dietary factors are important from a public health point of view,” Farzad Shidfar, a professor of nutrition at the Iran University of Medical Sciences, Tehran, and member of the university’s colorectal research center, and colleagues write.
“While some nutritional research has widely focused on single nutrients or foods in diet-disease relations, the overall diet could be more informative because humans typically consume a combination of nutrients and foods,” they write. “Dietary indices such as DAI are one of the approaches for this purpose.”
The study was published online in BMC Gastroenterology.
Measuring antioxidant intake
Previous research has indicated an inverse association between the DAI and inflammatory diseases, the study authors write, including gastric cancer, colorectal cancer, nonalcoholic fatty liver disease, and obesity. Studies have also indicated that H. pylori infection is related to deficiencies in vitamins A, C, and E, which have antioxidant properties.
In a case-control study, the research team compared the dietary intake of 148 patients with H. pylori to 302 healthy controls without infection. The patients in the H. pylori–positive group were recruited between June 2021 and November 2021 from the gastroenterology clinic at Rasoul-e-Akram Hospital in Tehran, where they were newly diagnosed with active infection and not yet under treatment.
The researchers calculated the DAI based on dietary intake information from a validated, 168-item food frequency questionnaire used in Iran. The participants were asked about their dietary intake based on the average day, week, month, and year. They also discussed serving sizes of food items, and to increase the accuracy of estimates, interviewers showed household measurements or serving sizes to confirm the measurements with participants.
The average age of the study participants was 39 years, and about 60% were women. Compared with the healthy controls, those with H. pylori were significantly older, had higher body mass index, and smoked more.
Overall, patients with H. pylori had a significantly lower intake of vitamin A, vitamin E, manganese, and selenium. Other differences in dietary intake – for vitamin C and zinc – were not significant.
The average total DAI was significantly higher in the healthy controls, at 7.67, as compared with 3.57 in the patients with H. pylori. The risk for infection decreased as continuous DAI increased.
After adjusting for several variables, the researchers found that participants with less than the median DAI values had an increased risk of developing an H. pylori infection.
“A balanced diet, especially high consumption of fruits and vegetables, might protect people against the consequences of H. pylori infection,” the study authors write. “On the contrary, a diet full of carbohydrates and sweets is related to a higher H. pylori infection prevalence.”