Adults with low vitamin D levels likely to have weak muscles

Washington: Vitamin D deficiency takes a toll on the muscle function in adults aged 60 and above, according to a new study. Maintaining skeletal muscle function throughout life is a crucial component of successful ageing, in promoting independence, mobility, quality of life and reducing falls and frailty. There is growing evidence that adequate vitamin D status may also be protective enough.

"Our results show that vitamin D deficiency increased the likelihood of poor muscle function in older adults and confirms the protective effect of physical activity," said Maria O'Sullivan, Associate Professor in Nutrition at Trinity College Dublin.

The study published in the journal Clinical Interventions in Ageing suggested that Vitamin D deficiency in older adults showed almost two times higher prevalence of muscle weakness (40.4 per cent) compared to those with vitamin D adequacy (21.6 per cent).

Similarly, impaired 'muscle performance' was three times higher in older adults with vitamin D deficiency (25.2 per cent) compared with vitamin D adequacy (7.9 per cent). Based on more complex statistical analysis, the study showed that vitamin D deficiency significantly increased the likelihood of impaired muscle strength and performance.

The study confirmed the associated benefits of physical activity. Older adults partaking in regular moderate physical activity had a significantly lower likelihood of poor muscle strength and physical performance.

In summary, vitamin D deficiency was associated with impaired muscle strength and performance in a large study of community-dwelling older people. It is generally accepted that vitamin D deficiency should be reversed to prevent bone disease, this strategy may also protect skeletal muscle function in ageing.

The findings are based on the analysis of data from 4157 community-dwelling adults aged 60 years and over, from the English Longitudinal Study of Aging (ELSA). Two validated measures of muscle function were assessed, namely handgrip strength and the Short Physical Performance Battery (SPPB).

"Maintaining muscle function is incredibly important, and often overlooked, in promoting healthy ageing. Addressing this through multimodal approaches that incorporate physical activity, reversing vitamin D deficiency and other modifiable diet and lifestyle components require further investigation," O'Sullivan opined.

"Overall our findings add weight to the evidence in favour of public health strategies to eliminate vitamin D deficiency in older populations," said Dr Niamh Aspell, first author of the study.