Vitamin D deficiency makes people vulnerable to coronavirus (COVID-19) infection, a new report reveals.
Vitamin D is crucial for the immune system: it improves the body’s defence response against infections, helps avert respiratory infections, and reduces the need for antibiotics.
The scientists point out that vitamin D is a seasonal vitamin and and so emphasise the need for vitamin D intake.
The study highlights that one-in-five Irish adults aged 55 and older are deficient during the winter and one-in-eight adults over 50 are deficient all year round.
Exposure to the sun for even 15 minutes daily can give the body a chance to make enough vitamin D.
In Northern countries, vitamin D cannot be produced in winter so the only chance to make it is between late March and late September.
The amount of exposure to the sun through this period also depends on factors such as rainy days, cloud cover, and so on.
In that case, with the correct diet and supplementation, deficiency can be avoided.
Vitamin D is found in foods such as oily fish including salmon, trout, mackerel, and sardines, eggs, liver, and some fortified foods including diary.
People who are in isolation at home and have no exposure to the sun are at risk of vitamin D deficiency.
The other vulnerable group are those who are physically inactive, obese, have chronic lung disease or asthma.
For these reasons it may be important to consume a diet high in vitamin D or take vitamin D supplements, which are available over-the-counter.
The research team say that vitamin D supplementation is advisable for people over 50 who don’t get enough sunlight or those who are ‘cocooning’ because of the COVID-19 outbreak.
Professor Rose Anne Kenny, the lead researcher of the study, said:
“We have evidence to support a role for Vitamin D in the prevention of chest infections, particularly in older adults who have low levels.
In one study Vitamin D reduced the risk of chest infections to half in people who took supplements.
Though we do not know specifically of the role of Vitamin D in COVID infections, given its wider implications for improving immune responses and clear evidence for bone and muscle health, those cocooning and other at-risk cohorts should ensure they have an adequate intake of Vitamin D.
Cocooning is a necessity but will reduce physical activity.
Muscle deconditioning occurs rapidly in these circumstances and Vitamin D will help to maintain muscle health and strength in the current crisis.”
About the author
Mina Dean is a Nutritionist and Food Scientist. She holds a BSc in Human Nutrition and an MSc in Food Science.
The report was published by Trinity College Dublin (Kenny et al., 2020).