A team of researchers are suggesting that more than a quarter of adults over the age of 50 are deficient in vitamin D and therefore urge supplement uptake and mandatory food fortification as policies most effective in combating deficiencies.
Vitamin D deficiency rises with age, and is also higher among smokers, those living alone and people from lower socio-economic backgrounds.
Severe vitamin D deficiency causes rickets in children and osteomalacia, or softening of the bones, in adults. It may also increase the risk of many other chronic non-bone related diseases, including immune function, cardiovascular disease and dementia.
Vitamin D is essential for bone metabolism and is thought to have beneficial health effects for muscle strength and non-skeletal health. Age-related conditions such as bone loss, fracture risk and falls are all linked to low levels of vitamin D.
Vitamin D can easily be treated with supplementation
The fact that that vitamin D can be treated easily with supplementation, means that it has significant policy and practice implications for Government and health services. There is no mandatory food fortification policy within the UK but if there was it could make a real difference.
Case in point is Finland, a country which gets less sunlight and is more northerly, but has a lower prevalence of vitamin D deficiency - less than 1% against 13%, which is due to a comprehensive public health policy of supplementation and fortification.
The longitudinal study looked at 6004 adults over 50 years of age found a clear divide between the north and the south of the UK, with those living in the south less likely to be vitamin D deficient. The researchers say this has to do with latitude, despite being a country with a short ranging latitude. With every 1 degree north there was an associated 11% increased risk of vitamin D deficiency.
London was the anomaly, with very high levels of vitamin D deficiency but this is thought to be a result of factors such as urban lifestyles, extremes of poverty and affluence and aggregation of people with chronic health conditions being more likely in cities.
The research team concluded:
The high rates of deficiency in the UK are similar to rates seen in other high latitude countries such as Ireland however other more northern countries such as Finland have implemented a successful vitamin D fortification policy which has all but eliminated deficiency in the population, such as policy could easily be implemented in the UK and Ireland.