VITAMIN D

Vitamin D is produced by the body when the skin is exposed to sunlight. It is also found in foods of animal origin. 

Vitamin D differs from other vitamins in that our bodies can make it upon exposure to sunlight. 
In its active form, it is considered to be a hormone. It has hormone-like effects on mineral absorption, bone mineralization and some secretions. 

Key Functions

Vitamin D is crucial for the development of healthy bones and teeth. Without it, the body cannot build or maintain strong bones. 
Vitamin D is a fat-soluble vitamin that plays a role in controlling calcium absorption, which affects bone development and is also essential for blood clotting. 
When vitamin D is in short supply in the body, less calcium is absorbed from food, and blood levels have to be maintained by taking calcium from the bones. 

Food Sources

Cod liver oil, herring, mackerel, sardines, salmon, tuna, margarine, and cheddar cheese
Usage
Check with your local market for the recommended daily intake of vitamin D.

Safety Evidence

People who avoid the sun completely (or get very little natural sunshine), the elderly population, vegetarians/ vegans, and pregnant and lactating women may all benefit from adequate or slightly higher levels of vitamin D.