Vitamin D is a group of fat-soluble secosteroids responsible for increasing the intestinal absorption of calcium, magnesium and phosphorus. It has received the nickname “vitamin of the sun”, as – in addition to its intake from certain foods – it is naturally produced by our own body when our skin is exposed to sun radiation.
Vitamin D, where does it help?
Osteoporosis: Vitamin D is traditionally considered to be the “bone vitamin”, as its main action is to increase the intestinal calcium absorption. Studies prove its contribution to the proper development and promotion of skeletal system’s health. It is given to treat or to prevent ricket in children, osteoporosis, bone pain (osteomalacia) etc. In addition, it is important for the prevention of fractures in people at risk for osteoporosis as well as for better calcium absorption and reduction of bone loss in people with kidney failure. Finally, it plays a significant role in reducing the risk of multiple sclerosis (Journal of the American Medical Association).
Immune system: Studies show that people who often suffer from seasonal flu or common cold have lower levels of vitamin D in their blood. These results confirm its contribution to the strengthening of the immune system. Moreover, according to the American Journal of Clinical Nutrition, it helps to reduce the risk of developing flu symptoms.
Cardiovascular system: Vitamin D has a proven clinical effect in reducing the risk of heart disease (Circulation Journal) as well as blood vessel diseases, such as high blood pressure and high cholesterol.
Factors that affect its composition
In Greece, as in other Mediterranean countries, someone would expect a sufficiency in vitamin D, due to extensive sunshine. However, numerous studies have shown that vitamin D levels, both in Greek population as well as in other Mediterranean people, are often lower than normal. This happens since the composition of vitamin D depends on a variety of factors, such as:
- Age: Body’s ability to produce vitamin D decreases over time
- Season of the year: In winter its production decreases due to lack of sunshine
- Skin color: Its composition is smaller in dark skin types
- Use of sunscreen products: Tend to “inhibit” the synthesis of vitamin D
- Other external factors (e.g., pollution)
Therefore, enjoy the sun (always with the necessary precautions) and include in your diet foods such as salmon, sardines, egg yolk, shrimps, fortified cereals and orange juice. Of course, in case of deficiency in vitamin D, consult your doctor first, before turning to the solution of supplements!
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