Plant-Based Diets Cut COVID Risk? Not Exactly

The Vegetable Garden of LlanerWe do admire the tenacity of folks who promote the virtues of a plant-based diet. But that admiration stops when we move on to the dimension of scientific rigor and objectivity. In BMJ Nutrition, Prevention, and Health, a group of researchers are claiming that plant-based diets “may be considered protective against COVID-19 infection.”

The only problem is a lack of evidence for that claim. All they have is an association in a relatively small study that can’t prove cause and effect. So it adds up to empty puffery, not science.

Scoring High Media Attention

Certainly, they’ve been quite successful in promoting this idea, generating 84 news stories in just ten days and scoring in the 99th percentile for media attention on Altimetric. With headlines like “Plant-based diets pack an antiviral punch against COVID-19,” it seems like a win for their mission to sell the amazing benefits from a diet based on plants.

The enthusiasm of these researchers is evident. Lead author Júlio César Acosta-Navarro told Everyday Health:

“Plant-based dietary patterns are rich in antioxidants, phytosterols, and polyphenols, which positively affect several cell types implicated in immune function and exhibit direct antiviral properties,”

Low Marks for Rigor and Objectivity

Enthusiasm is a poor substitute for scientific rigor and objectivity. Multiple experts in nutrition took issue with the study size (n=702) and observational design. For instance, Dr Gavin Stewart is Senior Lecturer in Evidence Synthesis at Newcastle University. He told the Science Media Center:

“This work presents interesting data but the authors’ conclusions do not adequately reflect the uncertainty inherent in small observational studies that are not designed to assess causal relationships. The conclusion that plant-based diets have a preventative role in COVID-19 infection is premature and not warranted.”

No Magic

Thus, the claims about plant-based diets packing a punch against COVID are nothing more than punchy pufferty. They’re grounded in magical thinking. Yes, plant-based diets can be nourishing and helpful for environmental concerns. But no, we should not count on them to protect us from COVID.

Click here for the study and here for some thorough critiques. For further reporting, click here.

The Vegetable Garden of Llaner, painting by Salvador Dali / WikiArt

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January 20, 2024

One Response to “Plant-Based Diets Cut COVID Risk? Not Exactly”

  1. January 20, 2024 at 7:48 am, Scott Butsch said:

    And you wonder why we can’t move forward as a society?
    For COVID, we’re told we should stick to a plant based diet, which goes well with all the evidence around taking zinc and have Plaquenil and bleach for back up.
    For Obesity, the barrage of mixed messages lacking evidence and continued bias statements lead people to believe we should stick to starvation and take laxatives because evidence based therapies like medications are dangerous and too costly.
    Other countries are far ahead of us.