Covid-19 Part 9:
Vitamin D levels significantly affect Covid-19 severity

Scientists stress urgent need for increasing vitamin D levels in people across the world

A strong immune system is vital for fighting viruses, so staying indoors is of little benefit to bolstering our defences. In ‘lockdown’, we spend most of our time in sterile indoor living environments, furiously scrubbing our hands with soap until we’ve erased all of the bacteria on our hands which we need to protect us. 

Our bodies are not exposed to microbes in the environment, and the ban on sunbathing and outdoor activities means many of us are not storing enough vitamin D. While all of these factors will be weakening our immune systems, leaving our bodies more susceptible to viruses gaining a foothold than before, vitamin D deficiency has emerged as the most worrying. The studies below have been used to urge vitamin D should be a priority, not just in covid-19 patients, but the wider public too. 

Study 1

A study analysed data from 10 countries and found a link between lower vitamin D levels and an over-active immune system. Lower levels of vitamin D were found in countries hit hardest by the virus. It was linked to both mortality and a hyperinflammatory condition caused by an overreactive immune system. This condition, called cytokine storm, can cause extensive lung damage and possible death. It is not the virus itself which causes death but the over-reaction and complications from the malfunctioning immune system. The idea of ‘boosting’ your immune system is often mic-understood by many people, because it’s obvious that an immune system that is ‘too’ efficient causes problems. 

Not only does Vitamin D enhance your innate immune system but it stops them from dangerously over-reacting, meaning that it could defend patients against severe complications for covid-19. It won’t decrease chances of getting the virus, but it is thought to cut mortality rate in half once you have contracted it. Interestingly, this is one theory for why children are less affected; their acquired immune system is not developed, the second line of defence which is the part which causes over-reactions. 

The authors noted that factors such as differences in healthcare quality, age distributions in population, testing rates or different strains of the coronavirus didn’t appear to play a significant role, in comparison. For example, the healthcare system in northern Italy is one of the best in the world. 

Study 2

Another study in Ireland stated the urgent need to supplement the general public and covid-19 patients in hospital because of its power in fighting against the onset of respiratory infections and serious complications. It showed how vitamin D supports the immune system in an umber of ways which fight against SARS-CoV-2, the virus that causes Covid-19.

It found that highest infection and death rates correlated with low vitamin D concentrations, in countries like SPain and Italy, which surprisingly both suffer from high rates of vitamin D deficiency. In comparison, scandinavian countries in northern latitudes display lower infection and death rates. Despite less exposure to sunlight, their inhabitants have higher vitamin D levels, which could be to do with supplementation in their diet. The authors explain this could be why some demographics of people are worse affected, because “deficiency is most prevalent with age, obesity, in men, in ethnic minorities, in people with diabetes, hypertension and in nursing homes.” 


For years we have been made to feel terrified of the sun, so much so that a family trip to blackpool pier in February prompts parents to smear suncream on to their children so thick you’d have your work cut out distinguishing them from a bottle of milk. You can almost hear the ghostbusters theme tune in the background.

However, it’s less funny when you realise that the ingredients of most sunscreens pose a far bigger danger than healthy amounts of sun. Carcinogens and highly allergenic synthetic ingredients will destroy the biodiversity of bacteria on our skin, which is possibly the most important part of the immune system. Wearing this amount of sunscreen damages your immune system in a double-pronged attack. Your skin microbiome, the ‘first line of defence’ against invading pathogenic viruses, will be destroyed, and vitamin D will not be being created in your body because of the lack of sunlight reaching your skin. 

Vitamin D deficiency could also explain why belonging to some ethnic groups appears to increase your risk of developing severe Covid-19 complications. People of Afro-Caribbean descent in the UK will not absorb as much vitamin D from the sun as Caucasians, which is why many immigrants from hot countries develop rickets among other problems. 

Not only does this raise big questions about how beneficial lockdown is to our health, when considering the wider picture, but, once again, it shows the incredibly unhealthy lifestyles we employ, year on year, are contributing massively to the severity of our current situation. It isn’t good enough to suddenly become a paragon of virtue because you wear a mask and social distance, when you yourself are clinically obese, never go outside and have destroyed the ecosystem of microbes on and in your body for decades.

The strain unneccesarily put on our health system by our incredibly unhealthy lifestyle is far, far, far larger than has been felt by this virus. Talk about closing the stable door after the horse, its foals, and all the pigs, have bolted.

What do you think? Read the next installment in the Covid-19 Review here!

Share on facebook
Share on google
Share on twitter
Share on linkedin
Share on pinterest

Leave a Reply

Your email address will not be published. Required fields are marked *