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Vitamin D and COVID-19: What You Need To Know

15th October 2020

15th October 2020

By Robyn Schaffer

The coronavirus pandemic has undoubtedly changed the way we live forever. Its consequences and ramifications are far-reaching across all areas of society, with government guidelines and recommendations changing by the day.

Over the past few months, vast amounts of information have been circulating in the media with advice for how to best protect ourselves against the virus. From government-approved masks, hand sanitisers, and social distancing, to weirder and wackier methods (think boiling banknotes to prevent the spread of germs), we’ve pretty much heard it all.

But one of the latest debates around things that could help in the fight against COVID-19 is that of vitamin D. Back in September 2021, a study in the US found that patients with sufficient levels of vitamin D were less likely to experience complications and die from COVID-19, while another found that it also reduced infection rates.



To help decipher the fact from the fiction, we spoke to some experts in the fields of health and nutrition to find out exactly what the deal is with vitamin D and how it could potentially help us fight against COVID-19.

Why is it important to get enough vitamin D?

Getting enough vitamin D is crucial for a number of reasons. Nearly every process in the body uses vitamins and minerals for that process to happen, and if the necessary vitamin or mineral isn’t there, the process can’t occur.

Vitamin D in particular helps us regulate the amounts of calcium and phosphate in the body, which are needed to keep bones, teeth and muscles healthy. A deficiency can lead to health conditions such as rickets in children and bone pain in adults, also known as osteomalacia. Other things that vitamin D helps with include brain health, supporting our nervous system and lung function, regulating insulin levels, cancer prevention, and protection from the flu.

“It’s not that some vitamins and minerals are more important than others, it’s that some are more difficult to get hold of, like vitamin D,” says Jo Travers, a dietician and evidence-based nutritionist. Travers continues: “We usually make vitamin D in our skin through the presence of sunlight, but if the sun doesn’t shine much where you live or you tend to cover your skin up, you can’t really do this.”

Why is there widespread vitamin D deficiency in society?

In places like the UK or Northern Europe, where the weather tends to be less sunny, obtaining the optimum vitamin D status can be difficult. According to national surveys, across the population approximately 1 in 5 people have low vitamin D levels. Travers says: “Because most of us work or spend a lot of time inside, and when we do go outside we cover up or use SPFs to prevent sunburn, we just don’t get enough exposure.”

While vitamin D can be found in a small number of foods including oily fish, red meat, egg yolks, and fortified foods such as fat spreads and breakfast cereals, it remains on the whole difficult to obtain in optimum quantities from diet alone, hence why supplements are often a popular alternative. Today, the government recommends that people consider supplementing with vitamin D in the autumn and winter to keep bones and muscles healthy.



Furthermore, Travers highlights that vitamin D deficiency is more widespread among certain social groups than others, including the elderly and people with darker skin. “These groups are also showing the worst outcomes for COVID-19,” she says. “Dark skin needs much more UV light to make vitamin D, while, as another example, some women from Asian communities cover up most of their skin and so they won’t really get any UV exposure.”

Can vitamin D actually help prevent or cure COVID-19?

As it stands, there is currently not enough evidence to support claims that vitamin D has the ability to prevent or reduce the risk of being infected with COVID-19. But what we can do is “look at the relationship between them”, Travers says. And what medical professionals have deduced is that while having sufficient levels of vitamin D will not cure you from COVID-19 or prevent infection and transmission, people with higher vitamin D statuses in their bodies may have reduced risk of symptom severity.

“We’re seeing people talk about prevention of infection and transmission but that’s not the case,” says Alex Ruani, chief science educator and co-founder of The Health Sciences Academy. “We’re just talking about risk reduction, and only in some patients, not all. But it’s also important to remember that you can be infected without showing any symptoms.”

What should you know when reading the different claims out there?

When it comes to the science behind our health, it’s pivotal to separate the true from the false. Ruani notes that another frequently asked question is: can vitamin D boost our immune systems? And while, on the one hand, vitamin D can provide a confirmed number of health benefits for the human body, she prefers to stay away from using the word ‘boost’ when it comes to COVID-19.

Why? “When you’re infected with COVID-19, the immune system is already so ‘boosted’, so exacerbated, and so over-reactive, that it leads to things like tissue damage, organ damage and organ failure,” Ruani says. “It’s your own immune system working against you. So, when people talk about ‘boosting’ your immune system, we don’t actually want that with COVID. We just want an adequate, sufficient, balanced and controlled immune response.”

How can you get the right amount of vitamin D?

Since there are some clear links between having sufficient vitamin D levels and reduced severity of COVID-19 symptoms, there are steps we can all take to help protect ourselves as much as possible.

Ruani adds that obese individuals may have a higher risk of developing a vitamin D deficiency since excessive fat stores can sequester the vitamin. Achieving a healthier weight helps to reduce this risk, while upping D intake levels in the meantime.

Ruani also adds that things like eating a healthy, balanced diet, exercising and getting the right amount of sleep also play a part in maintaining adequate vitamin D levels.

Next steps

If you're looking to supplement your vitamin D levels, let us introduce you to The Recover Capsules. These nootropic capsules contain research-backed ingredients that support the recovery process, reduce inflammation and regulate hormone activity. Containing vitamin D, among other ingredients such as maca, chocamine and selenium.

This is not medical advice and should not be treated as such. Do not rely on this information as an alternative to medical advice from your doctor or another professional healthcare provider. If you have any specific concerns or questions about any medical matter, you should consult your doctor or healthcare provider. You should never delay seeking medical advice, disregard medical advice or discontinue medical treatment as a result of the information in this article.

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Feature Marine collagen Bovine collagen Source Fish or other marine sources, often skin, scales or bones Cattle, usually hides or bones Common collagen types Mainly Type I collagen Type I and Type III collagen Often chosen for Skin hydration, elasticity and beauty-focused routines General collagen support, including skin and connective tissue Digestibility Usually hydrolysed into collagen peptides for easier digestion and mixing Also commonly hydrolysed into collagen peptides Taste and texture Can have a mild marine taste if not well formulated Usually more neutral, though this depends on the product Dietary considerations Not suitable for fish allergies, vegans or vegetarians Not suitable for people avoiding beef, vegans or vegetarians Main thing to check Source, collagen dose, peptide format and taste Source, collagen dose, peptide format and quality Is marine collagen worth taking?  For most people interested in skin health, marine collagen is a reasonable, low-risk supplement to try, as long as your expectations are realistic. The evidence for gradual gains in skin hydration and elasticity is reasonably solid. The case for hair, nails and joints is softer, but it's building. It also works best as one piece of a bigger picture and should be consumed alongside a protein-rich, varied diet, decent sleep, sun protection and staying hydrated. If you do give it a go, choose a hydrolysed product with a sensible dose and supporting nutrients like vitamin C, commit to a consistent 8 to 12 weeks, and judge the results for yourself. Whatever source you land on, quality and consistency are what turn a supplement from a hopeful purchase into a habit worth keeping. That is the standard we hold every formula to at Innermost: science over hype, quality ingredients and nothing you do not need. Whether you are looking at collagen, protein or everyday wellness support, the same rule applies: choose what fits your body, your goals and the routine you can actually stick to. If you're not sure where to start, our free nutritionist consultation can help you work out what actually fits your goals. Frequently asked questions  Is marine collagen better than bovine collagen?  Neither is outright better. Marine is primarily Type I and may appeal to those looking for a fish-derived source, while bovine offers Types I and III and is often cheaper. Can vegans take marine collagen?  Marine collagen comes from fish, so it isn't suitable for vegans or vegetarians. Vegan "collagen support" products work differently, supplying nutrients such as vitamin C that contribute to normal collagen formation rather than collagen itself. Does marine collagen taste fishy?  A good-quality hydrolysed marine collagen should be virtually flavourless. A noticeable fishy taste is usually a sign of a lower-quality product. How much Marine Collagen should I take? Most research points to an effective daily intake of somewhere between 2.5g and 15g of collagen peptides, with many of the skin studies sitting in the middle of that range. References Czajka, A., Kania, E., Genovese, L., Corbo, A., Merone, G., Luci, C., Sibilla, S., Siciliano, C. (2018). Daily oral supplementation with collagen peptides combined with vitamins and other bioactive compounds improves skin elasticity and has a beneficial effect on joint and general wellbeing. Nutr Res. 57. Click here. Farooq, S., Ahmad, M., Zheng, S., Ali, U., Li, Y., Shixiu, C., Zhang, H. (2024). A review on marine collagen: sources, extraction methods, colloids properties, and food applications. Collagen Leather. 6(11). Click here. Myung, S., Kim, J., Lee, Y., Choi, Y. (2025). Effects of collagen supplements on skin aging. Am J Med. Click here. Pu, S., Huang, Y., Pu, C., Kang, Y., Hoang, K., Chen, K., Chen, C. (2023). Effects of oral collagen for skin anti-aging: a systematic review and meta-analysis. Nutrients. 15(9). Click here Evans, M., Lewis, E., Zakaria, N., Pelipyagina, T., Guthrie, N. (2021). A randomized, triple-blind, placebo-controlled, parallel study to evaluate the efficacy of a freshwater marine collagen on skin wrinkles and elasticity. J Cosmet Dermatol. 20(3), 825–834. Click here. Hexsel, D., Zague, V., Schunck, M., Siega, C., Camozzato, F., Oesser, S. (2017). Oral supplementation with specific bioactive collagen peptides improves nail growth and reduces symptoms of brittle nails. J Cosmet Dermatol. 16(4), 520–526. Click here. EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA). (2010). Scientific Opinion on the substantiation of health claims related to biotin. EFSA Journal. 8(10), 1728. Click here. Read more