>>according to the findings of a preliminary study presented today at the Society for Endocrinology annual conference in Edinburgh. Vitamin D, which is both a vitamin and a hormone, helps control levels of calcium and phosphate in the blood and is essential for the formation of bones and teeth. Sources of Vitamin D include oily fish and eggs, but it can be difficult to get enough through diet alone. Most people generate vitamin D by exposing their skin to UVB rays in sunlight.
Previous studies suggest that vitamin D can block the action of enzyme 11-βHSD1, which is needed to make cortisol. High levels of cortisol may raise blood pressure by restricting arteries, narrowing blood vessels and stimulating the kidneys to retain water. As Vitamin D may reduce circulating levels of cortisol, it could theoretically improve exercise performance and lower cardiovascular risk factors.
Researchers from Queen Margaret University in Edinburgh gave 13 healthy adults matched by age and weight 50μg of vitamin D per day or a placebo over a period of 2 weeks. Adults supplementing with vitamin D had lower BP, and cortisol in their urine vs placebo. A fitness test found the group taking vitamin D could cycle 6.5km in 20 min, vs just 5km at the start of the experiment. Despite cycling 30% further in the same time, the vitamin D group also showed less signs of physical exertion.
~10M people in England may have low vitamin D levels. On average, 1 in 10 adults has low levels of vitamin D in summer, vs 2 in 5 in winter. Because people with darker skin are less efficient at using sunlight to make vitamin D, up to 3 out of 4 adults with dark skin are deficient in winter.
“Our pilot study suggests that taking vitamin D supplements can improve fitness levels and lower cardiovascular risk factors such as blood pressure,” said Dr Raquel Revuelta Iniesta. “Our next step is to perform a larger clinical trial for a longer period of time in both healthy individuals and large groups of athletes such as cyclists or long-distance runners.”
“Vitamin D deficiency is a silent syndrome linked to insulin resistance, diabetes, rheumatoid arthritis, and a higher risk for certain cancers,” said Dr Emad Al-Dujaili. http://www.eurekalert.org/pub_releases/2015-11/sfe-vdp102915.ph
Recent Comments