The evidence is mounting that a healthy level of Vitamin D in the body provides a natural immunity to many infections, including covid-19. A September 2020 study conducted by a team of researchers from the Boston University School of Medicine, Massachusetts on a cohort of 191,779 patients found that the association between lower SARS-CoV-2 positivity rates and higher circulating levels of 25(OH)D (commonly known as Vitamin D) “remained significant in a multivariable logistic model adjusting for all included demographic factors.” “SARS-CoV-2 positivity is strongly and inversely associated with circulating 25(OH)D levels, a relationship that persists across latitudes, races/ethnicities, both sexes, and age ranges,” the authors of the study noted.
That Vitamin D (fun fact: Vitamin D it is not a true vitamin, and can be considered a hormone, produced by the skin on exposure to sunlight as a pre-hormone steroid, which is then synthesised in the liver and kidneys to produce the active form) is an essential nutrient needed for the healthy growth and maintenance of the body is well known. It helps the body absorb calcium and it is needed by the muscular and nervous systems, and is vital for healthy immunity as well. However, in the absence of adequate sun exposure, getting enough Vitamin D into the body via what we eat is a bit trickier than it is for other vitamins like A and C. Most adults need around 600 IU of Vitamin D every day, according to data from the National Institutes of Health, USA.
It is still easier for those who consume fish and eggs—oily fish like salmon, swordfish, trout and cod are naturally high in Vitamin D while egg yolks contain a healthy amount as well—but vegetarians and vegans may find it tougher to include foods rich in Vitamin D in their diet and feel the need to consume Vitamin D oral supplements. However, that’s not to say you cannot add the nutrient to your vegetarian or vegan diet at all.
The foods listed below are good vegetarian sources of Vitamin D—just remember that contrary to what some innacurate online articles say, foods like cereals, oats and orange juice do not contain Vitamin D naturally unless the manufacturer has fortified it (which will typically be mentioned in the product information).
Mushrooms, particularly the portobello, shiitake and morel varieties, are rich in Vitamin D. One cup of portobello mushrooms can provide up to 600 IU of Vitamin D. Mushrooms create vitamin D from sunlight, much like our bodies. If you are not sure if the mushrooms you are consuming have been grown under sufficient sunlight, you can try placing any mushroom under the sun for 20 minutes—this will boost its vitamin D level.
In countries like the US and Canada, most pasteurized milk sold in cartons or bottles is fortified with Vitamin D, which is not naturally present in milk in high enough quantities. Although this is not a common practice in India yet (though it is on high the agenda of a current milk fortification project led by the National Dairy Development Board), a few brands do fortify milk with vitamins like A and D. The Food Safety and Standards Authority of India (FSSAI) has a list of brands on its website that sell milk fortified with Vitamin D, including Britannia, Creamline Jersey, Nestle (A+ variant), Mother Dairy and Nandini.
Butter made with non-fortified milk contains higher levels of Vitamin D than other non-fortified dairy products because its high fat content helps preserve the nutrient. “If milk and dairy products are not fortified, they are normally low in vitamin D, with the exception of butter because of its high fat content,” says the paper Natural Vitamin D Content in Animal Products published in the international journal Advances in Nutrition in 2013. However, keep in mind that the amount of butter you would have to consume to get a substantial amount of the vitamin may pose other health risks.
Tofu made from fortified soy milk
Although the levels of Vitamin D present in soymilk naturally is on the lower side, most manufacturers fortify branded soy milk with Vitamins A, D and other nutrients. Homemade tofu made from soymilk will contain higher concentrations of the nutrient, and is an easy way for vegetarians and vegans to add more Vitamin D to their diet. Around 100 gm of tofu will deliver almost 1000 IU of Vitamin D. However, do make sure that the brand of soy milk you’re buying is of the fortified variety.