"This really matters in a viral pandemic, as vitamin D is critically important in helping our immune system to resist viral infection, & to limit inflammation when infection does occur. When these arms of the immune system malfunction it’s a perfect storm. https://www.rte.ie/brainstorm/2020/1124/1180110-covid-19-vitamin-d-ireland/

"The high prevalence of deficiency in this country is living proof that optimal vitamin D levels cannot be achieved through our low sunlight exposure and poor dietary intakes alone. This highlights the need for supplementation across the population."

"For Irish adults, much evidence now suggests that...20-25 micrograms per day (1000 IU/day) is required to enhance immune function. Supplementation at higher doses under medical supervision is likely to be needed for obese individuals, those with darker skin or older adults."

"Given the recent findings linking vitamin D deficiency and Covid-19 risk, and in light of our high prevalence of deficiency, especially in winter; it’s imperative that public health advice addressing this issue is now urgently developed." Signed by 10 academic physicians/profs.