- stored in the liver and fatty body tissue.
- main form = cholecalciferol, which is found in certain foods and can be produced in the body by the action of sunlight on the skin.
Sources of vitamin D:
- main source is sunlight, sometimes called the 'sunshine vitamin'.
- Ultra-violet light from the sun reacts with a substance in the skin to produce vitamin D.
- Around 15 minutes, 3 days a week in the sun will manufacture it, and then stored.
- Other sources include: dairy produce, liver, oily fish, eggs, breakfast cereals, spreadable fat and margarines.
- Important for children and housebound elderly.
Functions of vitamin D
- Together with calcium and phosphorus develops and maintains bones and teeth.
- Helps healing of fractured bones.
- Helps prevent brittle bone disease or osteoporosis.
- Helps absorption of calcium from intestine.
symptoms of excess:
- If a toxic build up occurs, it can cause nausea, vomiting and loss of appetite.
Symptoms of deficiency
- Rickets: occurs in babies and toddlers, bone is unable to calcify or harden adequately so bends and deforms.
- Osteomalacia: occurs in adults, can cause bones to fracture easily, can cause back pain/leg pain/rib pain.
- Most likely to be developed in young children, pregnant women and breast feeding women due to extra demands on the body.
- People with darker skin are more at risk due to pigmentation in skin which reduces the ability of the skin to manufacture vitamin D from the sunlight.
- Asian ladies most at risk, due to being covered up outside due to religion.
- Elderly people who are house bound or living in a care home are easily lead to deficiency due to not being outside a lot.
- Intestinal problems which reduce the absorption of vitamin D are at risk.