Vitamin D

Vitamin D is essential to helping the body absorb minerals such as calcium and phosphate that are important for maintaining strong bones, teeth and muscles. The majority of the vitamin D that we absorb comes from our exposure to sunlight and a small amount from our diet, in foods such as oily fish, red meat, eggs and fortified foods.

How can we get Vitamin D?

It is very difficult to get enough vitamin D through diet alone, which is why the NHS recommends that most people should be able to get all the vitamin D they need from sunlight. From late March/early April through to September is the best time to get the vitamins that you need from being out in the sun for short periods with forearms, hands or lower legs uncovered.

It is not precisely known how much time that it takes for the body to manufacture Vitamin D this way, but the NHS recommends that you take care not to burn in the sun while doing so. Make sure that you protect your skin with sunscreen or cover up if you are going to be in the sun for a period long enough to cause burning. People with dark skin, such as those of African, African-Caribbean or south Asian origin will need to be exposed to sunlight for longer to make the same amount of vitamin D as someone with lighter skin.

It also should be noted that the body is unable to make vitamin D if you are sitting inside by a sunny window as the ultraviolet B (UVB) rays that the body needs to make it is unable to penetrate glass.

Winter sunlight and supplements

In the UK, our winter sunlight through the months of March to October does not contain enough UBV radiation for our skin to make vitamin D. During this time, we rely only on food sources in our diets to get the required amount instead.

New advice from the NHS recommends to ensure that you are getting enough vitamin D in your diet that adults and children over the age of one should consider taking a daily supplement containing of vitamin D, particularly during these winter months. These supplements are widely available from supermarkets and chemists with vitamin drops being available for breastfed babies up to age of one. Babies that are fed instant formula should not need a supplement as baby formula is fortified with vitamin D. These children should not be given a supplement until they are on less than 500ml of formula a day.

Who is at greater risk of deficiency?

Some people who get little to no sunshine exposure will not get enough vitamin D. This may include people that are frail or housebound, in an institution or a care home or usually wear clothes that cover up the majority of their skin. People with ethnic minority groups with darker skin may also find it difficult to get enough vitamin D from sunlight as darker skin makes less than lighter skin. The NHS advises these people to take a daily supplement of 10mcg of vitamin D all year round.

Problems caused by low Vitamin D

A lack of vitamin D in the body can lead to bone deformities such as rickets in children and a condition called osteomalacia in adults which can cause bone pain and muscle weakness. This is a condition where the bones have softened due to poor levels of phosphate and calcium; the minerals that vitamin D helps the body absorb.


Vitamin D supplementation can make an important difference to how you feel, especially if you suffer with chronic pain or muscle aching, combined with low mood. Taking between 700 and 1500iu’s is suggested unless you are severely vitamin D deficient. If you feel you may be severely deficient you can ask your GP for a blood test and you may be prescribed a loading dose of around 10-20,000iu’s per day for a short period of time.