Winter is coming and with it an increased number of hours of darkness. For a few people this causes Seasonal Affective Disorder, but the lack of light presents another very specific challenge to the over-50s, according to a longitudinal study on ageing carried out by Trinity College Dublin (TCD), and that is vitamin D deficiency. As I live in sunny Spain, this is one problem I don’t face, but it is an issue of growing importance for children and people over 50 in Britain and Ireland.
I was surprised to learn that one in four people in Ireland are vitamin D deficient during winter, particularly in the north and west of the island and it is one in eight people during the rest of the year. Given its proximity to the UK, it makes sense that similar areas in England, Scotland and Wales have the same problem and indeed, one in five people in the UK are D deficient.
Vitamin D declines with age
Vitamin D is “essential for bone metabolism and is thought to have beneficial health effects for muscle strength and non-skeletal health,” and it is an issue for those of us over 50, because deficiency rises with age. It is also more prevalent in smokers, people who live alone and those from lower socio-economic backgrounds, according to other studies published in the medical journals.
Supplementation is one solution, but the TCD research indicated that only 8.5 per cent of the participants in the study were actively taking vitamin D supplements. Fortification of food products is another way to combat the lack of sun during winter – one of the reasons those living in northern climates have the greatest deficiency – but the availability of products with added vitamin D is still quite limited, despite calls for the vitamin to be added to a wider range of foods.
Finland’s public health policy
Yet, the lack of sunlight is not the only explanation for deficiency. Finland, which is further north and gets less sunlight than the UK and Ireland, has less of a problem. In fact, only 1 per cent of the population is believed to have below acceptable levels of the sunshine vitamin. The reason for this is that the Finnish government introduced a comprehensive public health policy of supplementation and fortification, including in milk products. This is step advocated by British scientists, but the UK government “hasn’t found enough evidence to justify universal supplementation” says Dr Benjamin Jacobs, a consultant paediatrician who would endorse the fortification of milk.
It seems logical that the British and Irish governments should take the Finnish approach to protect the health of its ageing population as well as children. We may associate rickets with the 19th century, but they are returning amongst British children, due to lack of enough time spent outdoors in light. The same softening of the bones occurs in adults, and lack of this vitamin is also associated with heart disease, type 2 diabetes and a number of cancers.
So, what can you do apart from taking supplements? Adding more oily fish, eggs, cereals with D supplement, pork, tuna, tofu and fortified orange juice to your diet is one way to make sure you boost your D levels. And Mel Wakeman, a Senior Lecturer in Nutrition at Birmingham University suggests “spending 20-30 minutes between 11am and 3pm in the sun each day from April to September should enable us to make enough vitamin D to meet our requirements.”
As you can see, there are many ways we can prevent the health problems associated with vitamin D deficiency, including taking a winter holiday in the sun. Now, that’s one type of supplement everyone would love!