Though a study has shown this, a correlation has not yet been properly established.
A recent study published in BMJ Nutrition Prevention and Health noted that those who followed a plant-based or pescatarian diet had a smaller chance of moderate-to-severe COVID-19 when compared to the participants who did not follow a plant-based or pescatarian diet. To be specific, the study said that vegans and pescatarians had 73 percent and 59 percent lower odds respectively of moderate-to-severe COVID-19.
The self-reported information was obtained from healthcare workers from six countries who had been substantially exposed to COVID-19 patients.
However, this study did not establish the link between self-reported diets and COVID-19 severity or duration. The study has only been externally reviewed by two individuals and is yet to be fully peer-reviewed.
Another study published in the Journal of Public Health indicated that patients with lower consumption of poultry and fruit in the usual diet had a more severe form of the disease. It suggested that consuming more fruits and poultry, and drinking less tea, could reduce the severity of the disease.
The COVID-19 pandemic has given rise to a lot of potentially dangerous misinformation. For reliable advice on COVID-19, including symptoms, prevention, and available treatment, please refer to the World Health Organization or your national healthcare authority.