Researchers analyzed survey responses from 2,884 doctors and nurses working in France, Germany, Italy, Spain, the United Kingdom, and the United States. Investigators sought out workers who had extensive exposure to SARS-CoV-2, the novel coronavirus responsible for COVID-19 infection, and excluded workers who were only infrequently exposed to patients with the virus. Nearly 95 percent of the participants were doctors, and 71.6 percent were male.
The web-based survey, which was live from July to September 2020, included about 100 questions spanning the respondents’ medical history, current medications, lifestyle, COVID-19 symptoms, and food preferences. Researchers categorized respondents into one of three diet types based on their responses about how frequently they ate various foods: plant-based (high in vegetables, legumes, and nuts, and low in red and processed meats), pescatarian (a plant-based diet that includes seafood), and low-carbohydrate/high-protein.
According to the survey, 568 participants reported either symptoms consistent with COVID-19 infection or no symptoms but a positive swab test for the infection. Of those 568 cases, 138 clinicians reported moderate to severe COVID-19 infection, which was defined as having a fever, respiratory symptoms, respiratory distress, or low oxygen saturation; the remaining 430 said they had had very mild to mild COVID-19 infection, characterized by no or very mild symptoms, a temperature below 100.4, and no shortness of breath or gasping. No one reported having critical COVID-19, which was defined by being in the ICU, having respiratory or another organ failure, or needing a ventilator.
After analyzing the survey data, researchers found that respondents who followed a plant-based diet had a 73 percent lower risk of developing moderate to severe COVID-19; for those who followed a pescatarian diet, the risk was 59 percent lower. “We also found that those who followed low carbohydrate/high protein diets had greater odds of moderate to severe COVID-19 compared with those who followed a plant-based diet,” says Sara Seidelmann, MD, an internal medicine doctor at Stamford Health in Stamford, Connecticut, and a co-author of the study.
These associations remained even after factoring in body mass index (BMI) and coexisting medical conditions. Researchers controlled for several potentially influential variables, including age, ethnicity, medical specialty, smoking, and physical activity.
Investigators didn’t find an association between any type of diet and the risk of contracting COVID-19 infection or the length of the subsequent illness. Although what you eat and drink can make a difference in preventing, fighting, and recovering from infections including COVID-19, no foods or dietary supplements can prevent or cure these diseases, according to the World Health Organization (WHO). To protect yourself from getting or spreading COVID-19, the Centers for Disease Control and Prevention (CDC) recommends getting a vaccine. If you aren’t fully vaccinated, wear a mask that covers your nose and mouth and stay at least six feet away from people outside your household.