Vitamin D, also known as ‘colecalciferol’ or ‘sunshine vitamin’ is a fat-soluble vitamin synthesized naturally from direct sunlight. It is also found in foods such as oily fish such as salmon, sardines, herring and mackerel, red meat, liver, egg yolks and fortified foods such as most fat spreads and some breakfast cereals.
Vitamin D is essential for the absorption of calcium for strong bones and teeth and to strengthen our immune system. There is also research to suggest that it can help fight diseases such as multiple sclerosis, cardiovascular disease, depression and reduce the incidence of flu so it is an essential vitamin to have in the sufficient amount.
Although Vitamin D is readily available naturally, some people will not get enough vitamin D from sunlight because they have very little or no sunshine exposure or because of too much melanin in their skin. If you have dark skin, for example, you have an African, African-Caribbean or South Asian background – you may also not get enough vitamin D from sunlight. This is because Melanin, which causes skin pigmentation, lowers the skin’s ability to make Vitamin D.
This is as a result of darker skin having a greater response to sunlight exposure, producing more melanin which blocks the synthesis of Vitamin D. People with darker skins, therefore, need to spend more time in the sunlight to make the same amount of vitamin D as a lighter-skinned people. It is therefore recommended that darker-skinned people supplement themselves with 10 micrograms (400 international units) of Vitamin D daily as sunlight and food may not provide sufficient stores.
Sitting indoors on a sunny day cannot help you make Vitamin D on a sunny day either. This is because UVB, which is essential for vitamin D synthesis, does not penetrate glass. Similarly, in the UK, during the winter months, sunlight does not contain enough UVB rays radiation. We, therefore, need to depend on food and supplementation to get enough of this sunshine vitamin.
How much time you spend in the sun to make sufficient Vitamin D is unclear as it depends on your skin colour and how much skin is exposed. Although you cannot overdose from Vitamin D from sunshine you must follow appropriate sun safety advice and use an effective SPF to ensure that your skin is not burnt or damaged by the sun.
Sunbeds do not help in synthesizing Vitamin D and can cause skin cancer hence not recommended for Vitamin D supplementation.
Too much Vitamin D supplementation can lead to various side-effects such as high calcium levels which can affect your heart and bones. It is therefore important that you only take the recommended amount, which is 10 micrograms per day. If you are worried about low Vitamin D levels speak to your GP about this. The dose required for treatment of deficiency is different from that required for prevention and a simple blood test can help determine if you require treatment first.
For information on the most useful and effective sunscreens or any other skincare advice please book in for a virtual skincare consultation. Ask about our Obagi range medical-grade skincare, suitable for all colour skins.