Irish winters leaving older people with vitamin D deficiency, report says
Irish winters are leaving one in four older adults deficient in vitamin D, a new study has found.
However, even during the summer, when the body usually produces vitamin D, one in eight adults over the age of 50 have been found to be lacking the essential vitamin.
The vitamin, which is produced by the body after exposure to summer sunshine, is needed for normal bone health and for the prevention of conditions such as osteoporosis. A deficiency can be treated easily with supplements.
Researchers from The Irish Longitudinal Study on Ageing (TILDA) at Trinity College Dublin have discovered wide variations in vitamin D deficiency across the different provinces of the island of Ireland and that these are dependent on lifestyle.
People living in Northern Ireland, the North and West of Ireland, and those who were physically inactive, were much more likely to be lacking in the vitamin, according to the study.
The research, which was published on Monday in the Journal of Gerontology: Medical Sciences, also found that vitamin D deficiency increased with age.
In adults over the age of 80, 37% were deficient in winter, compared with 22% of 50-59 year olds.
Vitamin D deficiency was found to be more common in smokers (23%), people who live alone (21%) and those from a lower socio-economic background (17%).
According to the research, the use of vitamin D supplementation was low, with only 8.5% of the over-50 population taking it.
Lead author of the study and Research Fellow at TILDA, Dr Eamon Laird, said he hoped the data would help inform public health policy, in particular with regards to vitamin D food fortification and the targeting of supplements aimed at reducing endemic vitamin D deficiency.
"To place this in context, in a country such as Finland, which gets less sunlight than Ireland and is at a more northern latitude, actually has less prevalence of vitamin D deficiency than Ireland due to a comprehensive public health policy of supplementation and fortification," he said.
Dr Laird added that the research shows "striking differences in the prevalence of deficiency across different physical and lifestyle factors such as obesity, smoking and physical inactivity, all of which are modifiable risk factors."
Professor Rose Anne Kenny, Principal Investigator of TILDA, said sufficient vitamin D status is needed for normal bone health and for the prevention of debilitating chronic conditions such as osteoporosis.
She warned that new research has shown that vitamin D deficiency "may also be associated with heart disease, kidney disease, brain health and diabetes."
"If these associations are confirmed in other large studies, then the high rates of deficiency seen in the older adult population are of concern and, given that vitamin D can be treated easily with supplementation, this has significant policy and practice implications for government and health services," added Professor Kenny.