 What's the role of nutrition for both preventing and beating COVID-19? Nutrition-related myths on protection and treatment have been widely prevalent in this pandemic, and while there's no diet that completely prevents infection, there are certainly dietary steps we can take to minimize risk. Those with healthier diets in general seem to suffer less serious courses. But this appears to be an indirect benefit of lower rates of obesity and pre-existing medical conditions. I mean, that's great, but is there any diet that may have direct effects on the course of disease or susceptibility to infection in the first place? Well, plant-based diets have been shown to decrease the risk of suffering from other respiratory infections. In fact, plant-based seminaries during the pandemic of 1918 appeared to have been relatively spared. Why might a plant-based diet help? Vegetable nitrates, concentrated in dark green leafy vegetables, can be used to make nitric oxide, which is part of our lungs' first line of defense against infection. There are also polyphenol phytonutrients in plants that may directly inhibit viral infection. Then there are beneficial effects on our microbiome, which plays a key role in our system-wide immune function. Fiber-containing foods facilitate more of a symbiotic relationship with our gut bugs, whereas processed junk and animal foods can have the opposite dysbiotic effect. Fiber, concentrated in whole plant foods, is the single most anti-inflammatory food component, whereas saturated fat, concentrated in meat, dairy, and junk, is the most pro-inflammatory food component. And so, no surprise, those consuming more pro-inflammatory diets were at greater risk of suffering a severe course and of getting COVID-19 in the first place, up to nearly 12 times the odds, even after taking into account body weight, diabetes, and blood pressure. But this study only covered 60 COVID patients. How about 11,000 COVID patients? Diet-associated inflammation increased the risk of getting COVID-19 infection, suffering a severe course, and dying from the disease. Might this help explain why the COVID death rates were 100 times lower in Africa? Can a plant-based diet help mitigate COVID-19? Let's find out. In this study of COVID-19 illness severity in the elderly in relation to vegetarian versus non-vegetarian diets, statistically the non-vegetarians had up to like 20 times the odds of suffering a critically severe course of COVID, but that was based on only nine vegetarians. Now here, a study of thousands of front-line healthcare workers across six countries found that those eating plant-based diets had 73% lower odds of suffering a moderate or severe course of COVID-19, and even combined with pescatarians who eat fish, but no other meat, still had significantly lower odds. The biggest spread was between those eating plant-based versus low carb. Compared to plant-based healthcare workers, those eating low carb, high protein diets had nearly four times greater odds of suffering a serious infection. This may not seem surprising, given that many of the underlying risk factors for COVID-19 mortality, obesity, heart disease, high blood pressure, type 2 diabetes, can be controlled or even reversed with health enough plant-based diet and lifestyle, but the parent plant-based protection went above and beyond. The greatly reduced risk was independent of all those conditions. The researchers suggest that a healthy diet rich in nutrient-dense foods may be considered for protection against severe COVID-19. The one food group most associated with lower symptom severity in one outpatient study was legumes, followed by grains, the top sources of dietary fiber. The investigators suggest that the anti-inflammatory effects of the short-chain fatty acids released by our fiber-feeding good gut bugs may explain the connection. The healthcare worker study enrolled a few thousand people, Harvard researchers collected data from nearly 600,000 participants using a plant-based diet scoring system, where you get points for eating healthy plant foods, but points deducted from meat, eggs, junk, and dairy. And indeed, those scoring higher not only had a significantly lower risk of suffering a severe course of COVID-19, but also significantly lower risk of getting infected in the first place. And again, this was after taking comorbidities into account alongside non-dietary risk factors such as exercise and smoking, bottom line, the best available evidence suggests plant-based diets are beneficial in directly reducing the risk of severe COVID-19 symptoms and the risk of infection, even independent of other health-related factors. A more Mediterranean-style diet may reduce the risk of infection by 22%, while an even more plant-based diet may cut infection risk in half. For dealing with long COVID, a plant-based diet has been suggested based on the abundance of data showing positive associations of plant-based diets with improved immune function, neurotransmitter balance, pain and inflammation reduction, improved sleep and mental health. So in terms of lifestyle adjustments and long COVID management, large-scale promotion of plant-based eating may have the potential to improve physical and mental impacts, but this has yet to be put to the test. There was a study that suggested those who eat more vegetables are less likely to end up depressed, and those who eat more nuts, beans, and whole grains may end up less depressed, anxious, and stressed after COVID, whereas stress levels were correlated with higher meat intake. But the only interventional studies are like this, showing a detrimental impact on high-fat, high-sugar diets, but that's in Syrian hamsters, though there's definitely some unhappy hamster lungs on the crappy diet. All in all, adopting a healthy plant-based diet may be a powerful tool to decrease the risk of severe COVID-19 and should be promoted as a public health safety measure. And what are the side effects? A delay in aging and decreased disease? Maybe this is the booster we need. After all, if real effort had gone into encouraging and incentivizing healthier diets and lifestyles, we would not only have saved many more lives from COVID-19, but we would also reduce future mortality from all major causes of death.