Vitamin D: Micronutrient, Mega Important

The existence of vitamin D has been known about since the early part of the 20^th Century but interest and research into vitamin D has exploded in the last twenty years. Vitamin D was known to be important for bone metabolism, specifically preventing the disease of rickets in children, and osteomalacia in adults, but we now know that vitamin D has a plethora of effects away from the skeleton. Vitamin D seems to have a number of important roles such as supporting the immune system, reducing the risk of some cancers, reducing the risk of osteoporosis and maintaining muscle strength, and it even seems to be beneficial for improving mood and energy levels.

Vitamins in general are defined as essential micronutrients that the body can’t make on its own and therefore must be included in our diet. But vitamin D is unusual. Whilst it is contained in some foods such as oily fish, egg yolks and red meat, most of our vitamin D is made by our skin in response to exposure to sunlight. And herein lies the problem for those of us whole live on this damp, little island. Although fair skinned people can maintain vitamin D levels with just half an hour of midday sunshine to the face and forearms, two to three times a week, even this is difficult to achieve in the UK.

Unfortunately, between October and March most parts of the UK simply don’t get enough sunshine to produce adequate amounts of vitamin D. Therefore, many of us end up being deficient in vitamin D over the winter months - up to 40% of us according to some studies. And, given the increasingly indoor nature of our lifestyles, the situation in the summer is not always much better. Those with darker skin, or who keep their skin covered, are at even higher risk from this problem, as are elderly people living in residential homes, and young children.

Vitamin D deficiency is therefore something of an epidemic in the UK. Sadly, we are now even seeing cases of rickets in the UK amongst children despite the disease having all but disappeared by the 1950s. Rickets can lead to bone deformities, impaired growth and sadly, if it isn’t picked up, it can actually be fatal in children. In adults, the condition of osteomalacia can cause aches and pains, muscle weakness leading to a so called ‘waddling gait’, and possibly broken bones.

Despite the widespread prevalence of vitamin D deficiency, it is easily overlooked. The symptoms of vitamin D deficiency, particularly if the deficiency is mild, are often vague and difficult to define. Frequently the feeling of malaise or lethargy that may be caused by low vitamin D levels are attributed to something else, or just blamed on the general stresses of life. This is a real shame because replacing vitamin D is very straightforward.

Vitamin D supplements are readily and cheaply available over the counter. The recommended daily dose of vitamin D for adults is 400 International Units (IU) which is the same as 10 micrograms.

As vitamin D levels can be easily checked with a blood test and easily corrected with treatment, if you have symptoms suggestive of a vitamin D deficiency, it is worth taking the test.