What’s this new health drug that all the scientists are talking about? The one that is good for our bones, our mental health, our immune system, the one that prevents rickets….. Yes of course – it’s Vitamin D! This new “wonder drug” is now thought to provide a wealth of health and well-being benefits- and we don’t even need a prescription to get it!
As far back as 1922 Edward Mallenby showed that childhood deficiency in this compound led to rickets and over the course of eighty years or so we have pretty much eliminated rickets. Unfortunately in the last decade cases of rickets have risen alarmingly. In a Feeding for Life Report published last October one in four toddlers in the UK were found to be vitamin D deficient and in the US a massive one in three teens and adults are thought to have low levels.
We can get vitamin D from our diet but there are relatively few foods that provide it in adequate quantities, oily fish like tuna and mackerel are good sources, beef and egg yolks and some cheeses provide a little, but the main source of vitamin D comes from exposure to sunlight. The reason for the increased prevalence of rickets is likely to be complex (especially when considered worldwide) but ironically too little sun may be the most important cause in the UK. Children and teenagers spend less time outdoors than 50 or so years ago, increased traffic, safety fears and of course the lure of a good computer game make this a fact of life. But over vigilance from the dangers of the sun is also a contributing factor. In 2011 a school girl from the UK was diagnosed with rickets thought to be caused by her mother’s caution of the sun. No one is saying we should ignore the damaging effects of sunlight but overdoing the protection and limiting exposure to less than half an hour a day may do more harm than good.
And it’s not just children whose bones need vitamin D, in one study, postmenopausal women who presented at Accident and Emergency with a common wrist fracture were found to have lower than optimal levels of vitamin D and importantly for people over 65 years, higher doses of vitamin D can reduce the risk of a fracture by up to 30 %.
Nowadays we have even more reasons to ensure we get enough Vitamin D. There are quite a few studies showing that in Alzheimer’s disease people who have the condition have lower levels of vitamin D than those without. It’s not known yet whether this is causal or not, it could be that people with the disease were just less likely to go outside and the low levels of Vitamin D were coincidental, but if the opportunity arises, it’s another good reason to be in the sun when we can!
In addition to all of this, vitamin D now seems to be an important player in helping to protect against respiratory diseases such as asthma, emphysema and even tuberculosis. Just last year research highlighted that people who were severely deficient in Vitamin D in their blood had twice the risk of a respiratory disease or infection than those with the highest levels. The study authors hypothesised that there may be immune benefits associated with adequate vitamin D levels.
What does all this mean for us? Most importantly we should try to get outside every day, assuming of course, that’s possible. Sunlight filtered by windows or by high sun factor protection will not penetrate the skin sufficiently to stimulate the production of vitamin D. Twenty – 30 minutes should be adequate for most people although those with darker skin will require longer exposure and on cloudy days more time may be needed. In climates with less sunlight or for people unable to get out of the house a vitamin D supplement may be required.
So are you getting enough sunlight to top up your daily dose of vitamin D? We must not forget, of course, the sun’s damaging effects but it is important not to overdo that caution, let’s enjoy the summer a little more and make sure we get our daily allowance of this free health drug.