Vitamin D is a substance which helps the body absorb and store calcium. It is therefore important for growth and maintanence of bones and teeth.

Your body absorbs vitamin D from exposure to sunlight on your skin. 15 minutes of daily exposure is usually sufficient, although this can vary according to weather, time of year, amount of skin exposed and sunscreen use.

Vitamin D is also available in vitamin D-fortified milk, liver, fish, butter and egg yolks. Adults should have a daily intake of 400 international units (IU) of vitamin D. Excess (unused) vitamin D can build up in your body. Prolonged excessive intake of vitamin D can cause serious side-effects including weakness, vomiting, anxiety and kidney problems.