Pilot study shows vitamin D can protect against viral respiratory infections
Studies have suggested that vitamin D has a potential role in protecting against viral respiratory infections, and those with high levels of this nutrient have less severe symptoms of Covid-19.
A small pilot study at Nizam’s Institute of Medical Sciences on Covid-affected patients of Gandhi Hospital, Secunderabad (published in www.nature.com), states that improvement in vitamin D levels to 80 to 100 nanograms per millilitre (ng/ml) significantly reduced inflammatory markers without any side effects.
Dr Maheshwar Lakkireddy, additional professor and head of department of orthopaedics at AIIMS, Bibinagar, Hyderabad, and author of the study told The Indian Express that vitamin D was a potential immunomodulator and, along with other researchers, the study showed its adjunctive role in the treatment of Covid-19.
Titled ‘The impact of daily high dose oral vitamin D3 therapy on the inflammatory markers in patients with Covid-19 disease’, the study aimed at objectively investigating the impact of pulse D therapy in reducing inflammatory markers of Covid-19.
“This pulse D therapy was done on 130 patients with mild Covid symptoms. The patients were randomised into vitamin D (VD) and non-vitamin D (NVD) groups. The VD group received pulse D therapy (targeted daily supplementation of 60,000 IUs of vitamin D for eight or 10 days depending upon their body mass index) in addition to standard treatment. The NVD group received standard treatment alone.
When differences in variables between the two groups were analysed for statistical significance, it was found that vitamin D levels had increased from 16 ng/ml to 89 ng/ml in the VD group and a highly significant reduction of all measured inflammatory markers was noted. Reduction of markers in the NVD group, however, was insignificant, Dr Lakkireddy said.
Vitamin D is a molecule and has been popular for right from depression to respiratory infections, but experts are cautious as there is no sufficient evidence so that it can be translated from bench to bedside.
According to The Lancet Diabetes and Endocrinology issue dated January, vitamin D supplementation has been extensively debated with strong arguments in favour and against. Data on the function of vitamin D in bone growth and maintenance is clear and has informed clinical guidelines over the years. While data from some observational studies has suggested that vitamin D supplementation can lower the odds of developing respiratory infections, particularly in vitamin D deficient groups, randomised trials have yielded mixed results.
Dr Sanjay Pujari, expert member of the national Covid task force at Indian Council of Medical Research, said the same risk factors attributed to low vitamin D were associated with higher risk of severe disease. The expert said it could be interpreted as low levels of vitamin D leading to severe disease of Covid.
“Here, the causation is wrongly attributed; we need more evidence, and good quality randomised controlled trials are underway across the world,” he said.