Chronic metabolic conditions such as obesity and type 2 diabetes have been associated with increased risk of COVID-19 and serious symptoms once infected, but the impact of diet on these risks is unknown.

A recent study by the researchers of Massachusetts General Hospital (MGH) has found people who followed a healthy plant-based diet had lower risks on both counts, according to Science Daily.

The study, published in the journal Gut, has also found that the beneficial effects of diet on COVID-19 risk seemed especially relevant in people living in areas of high socioeconomic deprivation, per the science news outlet.

Lead author Dr. Jordi Merino said, “Previous reports suggest that poor nutrition is a common feature among groups disproportionately affected by the pandemic, but data on the association between diet and COVID-19 risk and severity are lacking.”

Dr. Merino and his team examined data on more than 592,000 participants of the smartphone-based COVID-19 Symptom Study from March 24, 2020, to December 2, 2020.

The participants completed a questionnaire that asked about their dietary habits before the COVID-19 pandemic. And the diet quality was assessed with a healthful Plant-BasedDiet Score, which emphasizes healthy plant foods such as fruits and vegetables.

Overall, 31,831 participants developed COVID-19. Individuals in the highest quartile had a 9% lower risk of developing COVID-19 and a 41% lower risk of developing severe COVID-19, according to Science Daily.

Dr. Merino said, “These findings were consistent across a range of sensitivity analysis accounting for other healthy behaviors, social determinants of health and community virus transmission rates.”

Co-senior author Dr. Andrew Chan said, “Although we cannot emphasize enough the importance of getting vaccinated and wearing a mask in crowded indoor settings, our study suggests that individuals can also potentially reduce their risk of getting COVID-19 or having poor outcomes by paying attention to their diet.”

Dr. Merino said, “Our models estimate that nearly a third of COVID-19 cases would have been prevented if one of two exposures – diet or deprivation – were not present.”

The study findings also suggest that we need public health strategies to improve access to healthy foods and address social determinants of health in order to reduce the burden of the ongoing pandemic.

“Our findings are a call to governments and stakeholders to prioritize healthy diets and wellbeing with impactful policies,” Dr. Merino explained, “otherwise we risk losing decades of economic progress and a substantial increase in health disparities.” The article first appeared in Science Daily.