Take a look at a couple of articles in the BMJ Nutirition and Health archives (https://nutrition.bmj.com/content/3/1/74 & https://nutrition.bmj.com/content/early/2021/05/18/bmjnph-2021-000272) present some incredible findings regarding diet and immunity, in case case immunity towards severe Covid-19 symptoms.
The second article concludes after studying nearly 3000 cases from 6 countries (including over 500 diagnosed with Covid) that those with a plant based diet fared better than other diet options, including keto, paleo and many other diets were much more likely to have less severe symptoms. “Participants who followed plant-based diets had a 73% lower chance of moderate to severe COVID-19 illness, whereas those who followed low-carbohydrate, high-protein diets were 48% more likely to have moderate to severe COVID-19 illness. “
The first article reviews the effect of many nutritional factors on immunity.
It is amazing how beneficial a plant based diet can be, so long as you get a great variety of foods to ensure all the minerals and vitamins you need!