Vitamin D also supports immune function, may support heart health, and may have anti-cancer effects. Vitamin D receptors are found in various organs, suggesting that it has broader health effects, including on the nervous and endocrine systems.
Recommended daily dose of vitamin D
Vitamin D requirements vary with age and physiological condition. The recommended daily allowance (AI) for infants (0–6 months) is 10 µg (400 IU). For children aged 1–18 years and adults, the recommended dose is 15 µg (600 IU) per day. Pregnant and breastfeeding women should also consume 15 µg (600 IU) per day.
Occurrence of vitamin D in food
Vitamin D occurs naturally in a few foods. The best sources are oily ocean fish such as salmon, mackerel, herring and sardines. It is also found in eggs and in fortified products such as some spreads. Skin synthesis of vitamin D, which occurs in response to UVB radiation from the sun, provides most of the vitamin to the body, and only about 20% comes from the diet.