More and more research is being published on vitamin D, looking at its specific effects that we might not think are linked to its consumption. Although weight and body composition are primarily determined by diet and lifestyle, it appears that vitamin D deficiency can exacerbate weight gain, and in turn, supplementation can benefit body composition.

Mixed results are quite common in vitamin D trials, as very different doses are used and the initial vitamin D intake of participants is not always taken into account. However, a recent study used a sufficiently high dose in people with low vitamin D levels.

It has been known that vitamin D supplementation was important for the foetus during pregnancy, but a recent study has highlighted a new aspect that may also benefit mothers.

Effects of vitamin D supplementation during pregnancy

In this randomised study, the effects of vitamin D supplementation on body composition were investigated in 90 pregnant women. Participants were divided into 3 different groups:

• One group received 4000 IU of vitamin D3 per day,
• The other group took 2000 IU of vitamin D3 per day,
• The third group received a placebo.

The study lasted for 12 weeks, at the end of which changes in the participants' vitamin D levels, body fat percentage and body fat were measured.

Results

Unsurprisingly, those who took 4000 IU of vitamin D3 per day had the biggest increase in vitamin D levels, but this was not the only benefit of taking more vitamin D.

Body composition measures such as body fat, body fat index and body fat percentage all improved significantly with 4000 IU of vitamin D3, and to a much greater extent than in the other two groups.

The research also points out that the body's need for vitamin D increases during pregnancy, and meeting this need is essential to achieve the most beneficial effects. In many cases, the 2000 IU of vitamin D3 per day was insufficient and in some cases even resulted in vitamin D3 deficiency.

Summary

Vitamin D supplementation is of paramount importance during pregnancy, not only for the health of the developing foetus, but also to help minimise changes in the body composition of pregnant women. It’s important to supplement vitamin D3 in proportion to body weight: with a higher body weight, we need more vitamin D to avoid vitamin D deficiency.