When you develop vitamin D deficiency, it means your body is only absorbing small amounts of calcium and phosphate. You need these minerals to keep your bones healthy.

Therefore, a deficiency in vitamin D puts you at risk of developing certain conditions – such as rickets (in children) and osteomalacia (in adults). These conditions cause pain and discomfort in the muscles and bones, which become weak and soft. In some cases, the bones may become deformed

Our main source of vitamin D is from sunlight on our skin. Because of this, the most common cause of vitamin D deficiency is a lack of sunlight. Vitamin D deficiency is most common in people who don’t spend much time outdoors, such as older people and people who live in nursing homes.

A shortage of vitamin D in the diet is another major reason for vitamin D deficiency. It can be difficult to get vitamin D in your diet, as it is naturally present in only a few foods

Some people are more at risk of vitamin D deficiency than others.
Those most at risk are:

•  people over 65,
•  people who don’t get out into the sunlight – for example, people in hospital or nursing homes,
•  dark skinned people,
•  people who cover up their skin with clothes, perhaps for cultural reasons.

Other at risk groups include people who are obese, children and pregnant or breastfeeding women.