Do Vitamin D supplements help?

A study of over 25,000 people above the age of 50 years from the United States, recently published in the New England Journal of Medicine, showed that Vitamin D supplementation did not reduce the risk of fractures. Considering that a large proportion of our population has low Vitamin D levels, should we continue taking the supplements?

Vitamin D is frequently prescribed with calcium supplements, especially in older women. Considering the current study, do you think it is needed?

This is a very controversial issue. We have always believed that Vitamin D helps in maintaining bone health but it is hard to know for sure, considering a large chunk of our population is deficient. Plus, it is not just Vitamin D deficiency, is it ? Our population has several other deficiencies such as iron deficiency leading to anaemia. So, how can we determine what is causing the persistent aches and pains or fractures.

If we need to make a programme decision on whether the elderly should be prescribed Vitamin D, we need to carry out a large scale study to see whether it helps. Some say that Vitamin D doesn’t prevent fractures but helps in the healing. It has to be evidence-based.

However, what we need to ensure while prescribing Vitamin D supplements is that the levels of the individual are checked. Most of the treatment is empirical and the serum test to determine the Vitamin D levels is not usually done. There are studies that suggest high levels can pose more of a risk than help.

So, who really needs Vitamin D supplements?

In our country, the most important group, where we know for sure Vitamin D supplements help, is the paediatric population. Children with the deficiency can develop rickets (a condition that causes bone pain, poor growth, and soft and weak bones leading to deformities in children).

We also need to see the impacts on vulnerable populations such as pregnant women and those with non-communicable diseases such as diabetes, which are on the rise now in India. (It is thought that lower levels of Vitamin D are associated with decreased insulin release and insulin resistance in the cells).

But again, what is very important, is we test the people before giving any sort of supplement because there are various types of deficiencies seen in India.

There is, however, research to suggest that the supplement does help those in countries where exposure to natural sunlight is limited. We might increasingly need it for people staying indoors in air-conditioned environment and sunlight-deprived apartments. You need at least 30 minutes in the sun every day to maintain normal levels of Vitamin D.

Your team conducted a study on Vitamin D levels in those with Type 2 diabetes, what were the findings?

Well, we did find a high level of Vitamin D deficiency and insufficiency of over 90 per cent. But that figure alone does not mean too much because the background Vitamin D deficiency was also very high in the population. We don’t usually test for it but whenever we did, more often than not they were deficient.

What about Covid-19? Vitamin D, Vitamin C and Zinc were some of the most commonly prescribed supplements? Did it help in any way?

A lot of things were prescribed during Covid-19. People believed that these supplements would boost the immune system and help in fighting the infection. But there is no evidence to suggest that people who took these supplements either did not get the infection or when they did, they had milder disease.

But we learnt a lot during Covid-19. There were several therapies tested and studies carried out to generate evidence. We should do similar large scale studies to understand which supplements help and which they don’t. There is not really a lot of evidence or robust trials for many supplements available in the market today.