Vitamin D: Nature’s Healer

When you go for your annual medical check up, a test that is often overlooked is that of your vitamin D status. It may come as quite a shock to find out how low your vitamin D level actually is.

Why is vitamin D so important?

Vitamin D deficiency is widespread in industrialised countries, where people have been conditioned to be afraid of the sun, to wear sun block when outside, and to spend most of their time indoors. Lack of regular exposure to sunlight could result in a vitamin D deficiency. In fact, it is extremely difficult for your body to obtain sufficient quantities of vitamin D without regular exposure to sunlight. More and more studies are highlighting the vital role of vitamin D in neuromuscular function, immunity and insulin response, as well as in brain and gut health.

Functions of vitamin D

It is becoming apparent that more and more people worldwide have insufficient vitamin D levels, which influences the functioning of many systems.

Skeletal development, bone health and neuromuscular functioning all require adequate amounts of vitamin D. Colds, flu and other infectious diseases such as tuberculosis, as well as cardiovascular diseases, have been linked with vitamin D insufficiency. There is also mounting evidence indicating that vitamin D may reduce the incidence of several types of cancer (breast, ovary, prostate, colon, oesophagus, pancreas and leukaemia), as well as type 1 and type 2 diabetes.

Children with insufficient vitamin D develop rickets at around six months of age, presenting with typical signs of skeletal deformities, growth retardation and muscle weakness.

Danish scientists recently reported that vitamin D is necessary to trigger the action of T cells; the killer cells of the immune system, so insufficient levels of vitamin D mean that these cells remain dormant and inactive.

Vitamin D and sun exposure

Vitamin D is a fat-soluble vitamin that is produced in our bodies when the skin is exposed to UV radiation from sunlight. In theory, a few minutes’ exposure to sunlight each day should provide us with sufficient vitamin D. However, we need to understand the working of UV rays to benefit in this regard. There are two primary forms of ultraviolet radiation from the sun: UV-A and UV-B rays.

UV-A rays are prominent all year round, even on cloudy days, and are able to penetrate through glass. These are the rays responsible for giving one that lovely brown tan, while at the same time making the skin wrinkled and leathery and, with excessive exposure, being a primary culprit for causing skin cancer.

UV-B rays, on the other hand, are largely blocked out by clouds and are not able to penetrate glass; yet it is UV-B that, from cholesterol, forms the precursor to vitamin D in the skin. In the presence of UV-B skin is capable of manufacturing vitamin D3, but this production is interfered with if you apply sunscreen or stay indoors at the sunniest times of the day in attempt to prevent skin cancer.

The best way to ensure optimal vitamin D levels is through intelligent exposure to sunlight and UV-B rays on your bare skin.

Dietary sources of vitamin D

Since so few foods contain vitamin D, humans typically obtain 90% of their vitamin D3 from sunlight and the balance from dietary sources. The best dietary sources of vitamin D3 are:

* Salmon
* Mackerel
* Other oily fish

As well as functional foods fortified with vitamin D such as:

* Milk
* Cheese
* Juices
* Cereals
* Baby food

With no exposure to sunlight, one would need to drink about 10 glasses of vitamin D-enriched milk in order to obtain the minimum daily requirement.

Prevalence of vitamin D deficiency

Vitamin D deficiency is quite common, and is being linked to a growing list of diseases and conditions affecting people of all ages. Recent research has shown that an alarmingly high number of people don’t get enough vitamin D during winter: nine out of ten adults have sub-optimal levels.

The only way to test your vitamin D status is to have your 25-hydroxy-vitamin D3 levels measured by means of a blood test. Levels of between 50 and 65 mg/ml are generally recommended for good health.

Vitamin D supplementation

It is difficult to satisfy the body’s requirement through diet alone and therefore the only other solution is to supplement adequately with vitamin D3 in soft gel form. Based on the most recent research, the current recommendation is 70 IU of vitamin D3 per kg body mass per day. As vitamin D is fat soluble, excess vitamin D can be stored in fatty tissue. In obese people vitamin D can get trapped in these tissues, creating a need for extra supplementation in order for them to obtain optimal vitamin D status.

Vitamin D deficiency is alarmingly common, and a growing list of diseases and conditions is being linked with it in persons of all ages. Visit your doctor and have your levels tested. You are very likely to be deficient in this vital vitamin, which influences the function of so many systems in the human body.

*Main source: Dippenaar, N: Understanding vitamin D. The South African Journal of Natural Medicine; November 2010