Vitamin D, also known as “sunshine vitamin” is a group of fat-soluble compounds. The most important ones for human bodies are vitamin D2 and vitamin D3. D2 naturally is present in plants, while D3 is synthesized by our organisms when we are exposed to sun rays. Actually, vitamin D should be seen more as a hormone than a vitamin. It is synthesized in our skin, but it is actually activated in a different place in our bodies – liver and kidneys.
Main benefits of vitamin D include:
- Promotes strong and healthy bones – helps absorption of calcium
- Prevents arthritis
- Boosts our immune system
- Helps fight tooth decay
- Stimulates body’s ability to regenerate the liver
- Clinical studies show that low level of vitamin D contributes to a higher risk of Alzheimer’s disease
- Recommended for pregnant woman to prevent high blood and sugar levels during pregnancies
- Regulates blood pressure
- Helps in treatment of psoriasis and eczema
- Prevents premature aging of skin
Foods that are rich in vitamin D include (per 100g) :
- Cod liver oil – 250μg
- Caviar – 12,1μg
- Salmon – 13,5μg
- Mackerel – 3,8μg
- Marinated herring – 12μg
- Canned tuna, sardines – 5μg
- Tofu – 3,85μg
- Hard boiled eggs – 2,2μg
As far as recommended daily dosage the numbers vary in different institutions. European union recommends 5 µg, United States Institute of Medicine 15 μg/day. Maximum upper intake level is defined at 100 µg/day. The dosages of vitamin D in supplements vary, depending of how much sunlight we are exposed to. During autumn and winter when there is not enough sunshine it is recommended to take vitamin D in form of supplements.
Vitamin D deficiency is typically caused by wrong diet and little exposure to UVB rays from the sun. It impairs bone mineralization and causes bone-softening diseases. Our nervous system and muscles do not function correctly. It affects our immunity and increases risk of getting diabetes, breast, colon, ovarian and prostate cancers.
Overdose of vitamin D is very rare and caused by supplementation with extremely high dosages of the vitamin. Symptoms can include vomiting, fatigue, lack of appetite, headaches, constipation, excessive feeling of thirst.
Best way to keep proper levels of vitamin D is exposure to sunlight, proper diet (lots of fish!) and supplementation of the vitamin in autumn and winter when sun is scarce.