According to the findings of a recent study published in "Calcified Tissue International", older adults having serum 25(OH)D levels < 30 nmol/L are at a higher risk of incidence of age-associated decrease in neuromuscular strength than those with serum levels ≥ 30 nmol/L. In people without osteoporosis and those who do not take vitamin D supplements, the threshold of risk is even greater (≤ 50 nmol/L).

Researchers investigated if serum 25(OH)D  insufficiency and deficiency are risk factors for dynapenia occurrence in people (age 50 years and above) and if osteoporosis or vitamin D use induce modification of these relationships. A total of 3205 volunteers of the English Longitudinal Study of Ageing (ELSA) study who were non-dynapenic at the baseline were followed for about four years. The serum levels of 25(OH)D, a marker for vitamin D, were tested at baseline and classified as adequate (> 50 nmol/L), insufficient (≥30 and ≤ 50 nmol/L), or deficient (< 30 nmol/L).

At the end of the four-year follow-up, dynapenia occurrence was assessed by a grip strength < 26 kg for males and < 16 kg for females. The behavioural, sociodemographic, biochemical, and clinical traits were adjusted in Poisson regression models. As found, serum 25(OH)D deficient was a risk factor for dynapenia occurrence (Incidence rate ratios [IRR] = 1.70). When only people without osteoporosis and those who did not utilize vitamin D supplements were examined, both serum 25(OH)D deficiency (IRR = 1.78) and insufficiency (IRR = 1.77) were reported to be risk factors for dynapenia occurrence.