Despite being a country with abundant sunshine, Vitamin D deficiency is fairly common in India. The country has also seen an increasing trend towards taking Vitamin D supplements, either as prescription medicine or as a nutritional input. A study comparing the effects of increased sunlight exposure versus Vitamin D supplementation, conducted by researchers at Jehangir Hospital in Pune and Royal Manchester Children’s Hospital in Manchester, found that the former not only led to an an increase in Vitamin D concentrations, it also brought down cholesterol.
Dr Vivek Patwardhan, Dr Anuradha Khadilkar and others at the research centre of Jehangir Hospital conducted the study on over 200 men and found that there was significant decline in total cholesterol concentrations in individuals who had increased sunshine exposure for at least six months. The study was published recently in the Indian Journal of Endocrinology and Metabolism.
Vitamin D deficiency is common worldwide, even in sun-rich countries such as India and those in the Middle East. Suboptimal concentrations of Vitamin D have been reported in over 50 per cent of the Indian population, possibly due to changing lifestyles, leading to reduced effective exposure to sunlight.
The effect of increased casual sunlight exposure on Vitamin D concentrations and lipid profile has not been studied earlier, said Khadilkar. “So, we tried to assess the effect of increased sunlight exposure, in comparison with Vitamin D supplementation, on Vitamin D status and lipid profile in Indian men (aged 40-60 years) with Vitamin D deficiency. A total of 203 men were enrolled in the study that was conducted in the last two years,” she said.
“Apart from other lifestyle changes, reduced sunlight exposure in populations that migrate from areas with higher sunlight to lower sunlight seems to have an unfavourable effect on lipid metabolism. But we do not have enough data on the issue,” said Khadilkar.
A large-scale study is being planned to find prevalence of Vitamin D deficiency, she said. A significant decline in total cholesterol in individuals, who had increased sunshine exposure, was also observed during the study.
“Our study demonstrates that with increase in sunlight exposure, there is improvement in Vitamin D concentrations and lipid profile, while, in comparison, orally administered Vitamin D had an adverse effect on lipid profile though it was not significant,” said Khadilkar
As a result of increased awareness in the medical community, and among the public, there is an increasing trend of consuming Vitamin D supplements either as prescription medicines or as a nutritional supplement. Although increased sunlight exposure may be a physiological alternative to oral supplementation in sun-rich countries, it is infrequently advised, possibly due to difficulty in implementing lifestyle modifications and the perceived risk of skin cancer, explained the researchers.