A plant-based or pescatarian diet—which includes fish and seafood—significantly reduces the odds of developing moderate-to-severe COVID-19, according to new research in BMJ Nutrition Prevention & Health.
The authors found that plant-based and pescatarian diets reduced the odds of severe disease by 73% and 59%, respectively. Moderate-to-severe COVID-19 infection, on the other hand, was 4 times as likely to occur in those following a low-carb, high-protein diet.1
“These dietary patterns may be considered for protection against COVID-19,” the authors wrote.
The case-control study included 2,884 front-line health care workers in France, Germany, Italy, Spain, the UK and the US, all of whom had extensive exposure to COVID-19. They were all registered with the Survey Healthcare Globus network for health care market research, which enabled researchers to identify clinicians whose profession increased their risk of COVID-19 infection.
Participants responded to an online survey—active from July to September 2020—with details about their dietary patterns over the previous year using a 47-item food frequency questionnaire, as well as the severity of any COVID-19 infections they experienced. Details about personal background, medical history, medication use, and lifestyle also were collected.
Diets were grouped into 3 categories:
COVID-19 symptoms or a positive swab test result was reported by 568 participants, with 138 with moderate-to-severe infection and 430 with very mild or mild infection. After factoring in potentially influential variables, including age, ethnicity, medical specialty, and lifestyle, respondents following plant-based or plant-based pescatarian diets had 73% (OR 0.27, 95% CI 0.10 to 0.81) and 59% (OR 0.41, 95% CI 0.17 to 0.99) lower odds of moderate-to-severe COVID-19 severity, respectively, compared with those who did not.
Respondents who reported following low carb, high protein diets had greater odds of moderate-to-severe COVID-19 (OR 3.86, 95% CI 1.13 to 13.24), compared to those whose diets were plant-based. Researchers found no association between self-reported diets and COVID-19 infection or duration.
“Future studies with detailed macro-and micronutrient data are warranted to study associations between dietary intake and COVID-19 severity,” the authors concluded.
Kim H, Rebholz CM, Hegde S, et al. Plant-based diets, pescatarian diets and COVID-19 severity: a population-based case–control study in six countries. BMJ Nutrition, Prevention & Health. 2021;bmjnph-2021 000272. doi: 10.1136/bmjnph-2021-000272