How are your vitamin D levels?

Vitamin D has such an influence on a wide range of biological activities that it has been renamed by many the 'miracle vitamin'.

Sources of vitamin D

As any other vitamin, vitamin D comes from food. More specifically you will either absorb vitamin D3 if it comes from an animal source (e.g. Salmon, Sardines, Tuna, Dairy Milk, Eggs) or vitamin D2 if it is from a plant source (e.g. shitake mushroom). Both vitamins D2 and D3 then need to be transformed to be able to be used by the body.

Vitamin D is a vitamin with a special status because it is the only one that you can simply get by spending time in the sunlight. Sunlight promotes the vitamin D synthesis from cholesterol in the skin cells and this is the best form as it is immediately used by the human body. This is why vitamin D is often referred to as the sunshine vitamin.

Functions of vitamin D

Vitamin D is mainly known for its endocrine function that increases calcium and phosphorus absorption, which regulates bone mineralisation and bone health.

However, it is now proven that vitamin D has also an influence on a number of other conditions such as cardiovascular health, immunity, autoimmune conditions, insulin regulations, mood and cell differentiation.

So it is all the more so important to make sure you have the appropriate level of vitamin D. The optimal levels are established at 50-150nmol/l. It is interesting to note that a deficiency or an excess would be as harmful and tend to have the same signs and symptoms.

Situations and conditions requiring extra attention

Vitamin D production in skin depends on three factors which are; the latitude, season and time of day. This means that sun exposure in the UK in winter is not sufficient for the natural production of vitamin D.

People with darker skin, covered skin or using sun cream synthesise less vitamin D.

Certain types of medication deplete vitamin D levels. Always make sure to check this with your practitioner to avoid deficiency in the long term.

People who are obese or with an indoor sedentary lifestyle are more likely to be deficient because the vitamin would not be as bioavailable.

People with digestive issues such as IBD, small bowel resections or fat malabsorption.

Pregnant and breastfeeding women, as well as children under the age of five.

The elderly have a reduced capacity to synthesise the vitamin.


Always remain sun safe. Getting sunburnt will not help to raise your vitamin D levels.

Do get your vitamin D levels checked at least once a year in autumn. GPs can test you, or you can do a private finger prick test for £38.

Having the right levels of vitamin D alone can make a substantial difference in your health and in your life.  

Nutritionist Resource is not responsible for the articles published by members. The views expressed are those of the member who wrote the article.

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Written by Severine Menem

Severine Menem is a Nutritional Therapist & Health Coach.… Read more

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