New research from the Trinity-based Irish Longitudinal Study on Ageing (TILDA) has shown that vitamin D deficiency is associated with poor muscle function in adult ages over 60.
The research team has said that while resistance exercise is known to preserve muscle function, there is growing evidence that adequate vitamin D status may also be a factor.
The researchers found that muscle weakness was twice as high in adults with a Vitamin D deficiency compared to adults with a Vitamin D adequacy.
Similarly, impaired “muscle performance” was three times higher in older adults with vitamin D deficiency compared with vitamin D adequacy.
In a press statement, Maria O’Sullivan, an associate professor in nutrition at Trinity, said: “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.”
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).
Dr Niamh Aspell, the first author of the study, added in a press statement: “Overall our findings add weight to the evidence in favour of public health strategies to eliminate vitamin D deficiency in older populations.”
“Future research, however, should identify and focus on older adults with vitamin D deficiency and aim to better understand if reversing this deficiency improves skeletal muscle function.”
Vitamin D is often referred to as the “sunshine vitamin”, as a major natural source of the vitamin is the synthesis of cholecalciferol in the skin through a chemical reaction that is dependent on sun exposure. Its primary function is to facilitate the absorption of calcium in the body.
In countries such as Ireland, which receive insufficient sunny weather, vitamin D can be obtained through supplements or fortified foods. However, In Ireland, fortification of food products with vitamin D is voluntary and few manufacturers do this.
There are currently no government guidelines concerning vitamin D intake.
In a press statement, Dr Eamon Laird, a co-author of the study and a Trinity Research Fellow, said: “Vitamin D deficiency and physical activity are modifiable factors. Some countries, for example Finland, have successful implemented a vitamin D food fortification policy which has all but eliminated deficiency in the population.”
“Such a policy could similarly be implemented in the UK and Ireland for older populations”, he added.
Last year, TILDA researchers found that vitamin D deficiency is associated with an increased risk of depression in older adults.