Here Comes The Sun – 19 March 2014
Emerging into the sunlight after months of rain makes me feel like Mole in Wind in the Willows, burrowing his way out of a dark and gloomy place. I sit blinking in the brightness, smelling the earth that is still damp and if I had whiskers, they would certainly be twitching. Let’s not discuss those few that have emerged of late on my chin as they have been dispatched and surely won’t ever reappear – oh the suffering of the woman of a certain age!
All this sunshine puts me in mind of Vitamin D, levels of which are often deficient at this time of year in many of us who inhabit the northern hemisphere. This particular vitamin is not easily absorbed through what we eat, but rather through our exposure to sunlight. Our friend cholesterol plays a crucial role in helping to turn sunlight into Vitamin D. This is but one of many crucial roles cholesterol plays in keeping us healthy, a point that is easily forgotten in all the bad press it receives.
80 – 90 % of the Vitamin D we need is supplied by the sun, specifically the UVB rays. The sunlight interacts with the cholesterol in our skin and is transformed into Vitamin D. In order to get enough sunlight we need about ½ hour of midday sunlight to fall directly on our skin. Of course too much sun – especially in the summer months – is inadvisable so don’t throw away the sunscreen. As someone who never ventures into the sun without a wide brimmed hat, I have taken to rolling up my sleeves while out for my ½ hour of brisk walking. This way I get my allocated exposure without burning. Any additional sun time is spent under a high factor protection cream or in the shade. Weighing up the risks of skin cancer and the dangers of vitamin D deficiency is one of those balancing acts.
As with most health related advice, sun exposure time for optimal vitamin D absorption is not a simple matter. The Vitamin D Council recommends exposing a wide area of skin at midday for about half the time it takes for your skin to turn pink and start to burn. Each of us will differ in how much time that involves. Fair skinned people require less time in the sun than their darker skinned peers while older people need more exposure time than the young. So as not to become too obsessive-compulsive about it all, I think ½ hour sounds an average worth working towards. This is especially important in climates where we spend most of the year indoors.
If you are wondering what foods do contain vitamin D, it is mostly the oily fish family which we should be eating 2 – 3 portions of a week in order to consume the good fats that help with cholesterol control. Of course they also contain omega 3s about which I will be writing shortly. In addition to these fish, some cereals, juice and margarines are fortified with vitamin D but I don’t eat these as margarine is unhealthy (in my view) and the cereals and juices are packed full of sugar. Please note though, that you cannot eat your way to good levels of Vitamin D as the foods that do contain it, have very little in them. If you are deficient you may need to take a supplement. Best to discuss with your doctor.
Vitamin D deficiency is very common – especially in the over 65s – and has potentially harmful effects. In women, it increases the risk of osteoporosis which is itself correlated with higher risk of cardiovascular disease. Treating women with calcium supplements without regard to their vitamin D level can reduce the efficacy of the calcium on bone strength, with vitamin D having more effect on increasing bone density than calcium.
A growing body of research suggests that vitamin D deficiency could be one of the contributing factors in cardiovascular disease. This seems due to its association with high blood pressure, diabetes and inflammation, all of which are risk factors for cardiovascular disease.
How do we know if we are deficient in Vitamin D? Only a blood test can reveal our levels of stored vitamin D. You can ask your GP to arrange this if you are having blood tests for cholesterol or other things or you can order a home testing kit online if you are so inclined.
I am going to use the sunshine to boost my wintery levels, get outdoors most days, keep walking with the sleeves up while recalling that old adage ‘ may hay while the sun shines’.
You can follow this link for an extensive article on Vitamin D creation, supplements and everything you didn’t realise you needed to know on the subject.