Vitamin D
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Finally, the media and the medical world is waking up to what doctors and scientists with knowledge in nutrition have been saying for over 40 years – our health suffers unnecessarily due to a lack of Vitamin D – the “Sunshine vitamin”.
It is so important to get enough sun and to eat a diet rich in Vitamin D as all the following diseases are associated with deficiency:
Diabetes
Osteoporosis
Arthritis
Coughs and colds
Heart disease
Increase risk of stroke
Dementia and Alzheimer’s disease
Cancer
Various skin diseases
Rickets
Multiple sclerosisA detailed description of these and other conditions related to Vitamin D deficiency can be found on the “Jen Reviews” site - with numerous links both for the professional and for those interested (1).
Having the right amount of Vitamin D is essential for our wellbeing. Over the years I have routinely performed hundreds of tests on people for Vitamin D, and I have been pointing out many studies which show astonishingly high rates of deficiency. One study, published in the London borough of Tower Hamlets in January 2011, showed 80% of the Caucasian (fair skinned) population had insufficient levels of Vitamin D or were frankly deficient. Around 50% of the Asian and black skinned population had actual deficiency and approximately 46% had what is described as an insufficiency (2).
To correct Vitamin D deficiency it is important that you are exposed to sunlight or ensure you take supplements.
There are many different types of skin colour. These range from the fair, freckled skin through to the dark Equatorial skin found in Africa. Different pigmentation allows an individual to spend more or less time in direct sunlight. Lack of sunshine, in our climate, along with the highly publicised fear of skin cancer are two major reasons why we have a surprisingly high rate of Vitamin D deficiency in the general population.
Age and various diseases also decrease the production and absorption of Vitamin D. As stated in the list above, vitamin D is associated with the healthy function of the arteries and, therefore, it protects against heart attacks and strokes. It is essential to the immune system (especially in conditions where the body attacks itself - autoimmunity) and normal function of the nervous system.
Vitamin D is anti-cancerous. It is necessary for mineralization of the skeleton (osteoporosis). It is important in nerve electrical conductivity, muscular contraction and our cells’ sensitivity to insulin (therefore reducing the risk of diabetes). One third of childhood diabetes is thought to be preventable through the simple expedience of raising Vitamin D levels. Surprisingly this had been established as early as 2001 but the study was criticized and did not get the publicity that it deserved (3).
I believe that through the summer months and when in sunny climes, rather than avidly and consistently covering ourselves with clothes, hiding in the shade or using sun creams, we should all learn how much sun we can take before our skin starts to become pink (or equivalent coloration) indicating a ‘pre-burning’ of the skin. For some it may be as little as 10 minutes in a strong sun whereas the darker skin may be able to expose itself all day. Once we have established our own tolerance, I recommend that as much skin is exposed as possible, allowing for social situations, for that length of time each day. After that the use of sun cream, protective clothing and staying in the shade is, of course, important to avoid the risk of skin cancers.
Vitamin D rich foods include oily fish - salmon, halibut, herring, sardine and mackerel. We have to be a little wary of these fish containing antibiotics and growth hormones found in farm produced stock, but then we have to recognize that wild fish can contain industrial and human waste such as mercury and oestrogens. Try and find sources certified organic or do not have more than 2 portions of these fish each week. Eggs and liver provide some vitamin D as does full fat milk and, although I am not a great supporter of processed foods, certain cereals, soya, other alternative milks are fortified with Vitamin D.
It could be argued Vitamin D supplementation should be taken by anyone with a deficiency or an insufficiency and testing though the late autumn or winter might be a sensible action on all our parts. Ensure the source of supplementation is not contaminated. Trained nutritionists will have their preferred brand. For years the recommended dosage has been around 400iu for adults and half that for children, but many authorities now deem that to be much too low. The Vitamin D Council, a non- profit organization in the USA, recommends the following
Healthy children under the age of 1 years – 1,000 IU.
Healthy children over the age of 1 years – 1,000 IU per every 25 lbs of body weight.
Healthy adults and adolescents – at least 5,000 IU.
Pregnant and lactating mothers - at least 6,000 IU.
Additionally, children and adults with chronic health conditions such as autism, MS, cancer, heart disease, or obesity may need as much as double these amounts.
The USA safety levels are now set at 2,000iu although there is very little evidence of toxicity until doses of 40,000iu are used over a period of time.
References