COVID-19: Can vitamin D reduce your chances of contracting the infection? Here's what experts have to say
The coronavirus pandemic has raised a new question: are patients with vitamin D deficiency facing a higher risk of death?
Some experts suspect a link between vitamin D deficiency and high death rates. Others believe patients with levels of the nutrient might have a 20-fold higher risk of ending up in the ICU. "Has anyone looked at vitamin D levels in ICU patients as related to mortality? There’s substantial evidence there’s a relationship," Dr Vatsal G Thakkar, Clinical Assistant Professor of Psychiatry at the New York University School of Medicine, tweeted recently.
Can vitamin D protect you from coronavirus?
Vitamin D is believed to boost immune system health. Our body produces it when exposed to sunlight. But people can only get their daily boosts from food such as oily fish, eggs, and fortified food products, and by popping supplements. Children with low levels of the nutrient suffer from rickets, a condition that leads to softening and weakening of bones.
Currently, there is no evidence to suggest that vitamin D reduces people's risk of contracting the disease. Researchers are conducting clinical trials to investigate if it can prevent and treat COVID-19. In the meantime, another study is evaluating if high doses can help older patients.
According to Prof Jon Rhodes, emeritus professor of medicine in the UK, vitamin D might stop an immune system overreaction: studies suggest some patients with severe COVID-19 die of this overreaction -- and not the virus itself.
Professor Rhodes believes the nutrient can tone down the overreaction -- but researchers are yet to study its role in taming the immune system.
Why are researchers studying vitamin D?
As more countries across the world shut down, some researchers are suggesting vitamin D supplements might help make up for the lack of exposure to sunlight.
Previous research has linked vitamin D deficiency to respiratory infections such as pneumonia, tuberculosis, and bronchiolitis. Some research has shown that having healthy levels of vitamin D, and popping vitamin D supplements, can improve the health of the immune system. Additionally, one review looked at more than 10,000 people from 14 countries and found that vitamin D supplements decrease the risk of serious risk respiratory infections by 12%.
Other studies have also suggested that the nutrient can protect people from respiratory infections, especially children. But the World Health Organization (WHO) warns that it is too early to make recommendations and that more studies are needed.
What are the recommended doses?
About 42% of the adult population in the US have low vitamin D levels. The National Institutes of Health recommends a daily dose of 10–20 micrograms of the nutrient for adults. For infants and children, it is 10 and 15 micrograms, respectively. Pregnant and breastfeeding women can consume 10 micrograms.
But consuming too much of it can be toxic. It can lead to a buildup of calcium in the blood. The condition could lead to nausea and vomiting, weakness, and frequent urination. In the long run, it can trigger bone pain and kidney problems.