Vitamin D deficiency may damage muscle function, especially in older adults

NEW SOUTH WALES, Australia — Vitamin D tends to act like a cure-all for humans. From preventing colds, to relieving skin problems, to even fighting off COVID-19, the “sunshine” vitamin does it all. Now, a new study finds not having enough vitamin D may also mean bad news for your muscles. An international team finds vitamin D deficiency leads to impaired function, performance, and recovery — especially in the elderly.

Although the sun is famous are providing vitamin D through ultraviolet light, humans also obtain it through eating certain foods. These include fatty fish, egg yolks, and cheese, however, many also turn to vitamin supplements instead.

According to studies, upwards of 40 percent of U.S. adults may be deficient in vitamin D. Researchers, exploring vitamin D in muscle performance of older people, examined a mouse model over a period of three months.

They also collected tissue and blood samples monthly to quantify vitamin D and calcium concentrations in the animals. This allowed the team to assess biomarkers of muscle mitochondrial function their total numbers during the study.

Vitamin D may fuel the energy producers in cells

After feeding the mice a diet deficient in vitamin D for three months, researchers discovered significant muscle impairment in their subjects. Skeletal muscle mitochondrial function dropped by up to 37 percent. However, study authors say neither the number of mitochondria nor a reduction in muscle mass contributed to muscle impairment.

Instead, the findings point to vitamin D deficiency damaging mitochondrial function — the energy producers of the muscle cells. Therefore, preventing vitamin D deficiency in older people may help maintain muscle performance and reduce the risk of muscle-related diseases such as sarcopenia.

“Our results show there is a clear link between vitamin D deficiency and oxidative capacity in skeletal muscle,” Dr. Andrew Philp from the Garvan Institute of Medical Research in Australia writes in a media release.

“They suggest that vitamin D deficiency decreases mitochondrial function, as opposed to reducing the number of mitochondria in skeletal muscle. We are particularly interested to examine whether this reduction in mitochondrial function may be a cause of age related loss in skeletal muscle mass and function.”

The findings appear in the Journal of Endocrinology.

SWNS writer Joe Morgan contributed to this report.