The Valter Longo Onlus Foundation June 29 2021
Vitamin D, also known as calciferol, is a fat-soluble vitamin that is present in our body in two different forms: ergocalciferol (D2), and cholecalciferol (D3). D2 is present in plants and is synthesized by plants through photosynthesis; D3 is found in animal products and is synthesized in the skin with sunlight exposure.
WHY DO WE NEED VITAMIN D?
Vitamin D performs vital functions in our body. Vitamin D3 promotes the synthesis of the “feel good” hormones: endorphins, serotonin, and dopamine. In fact, vitamin D deficiency can lead to malaise and a lowering of mood, to the point of causing depressive states. Vitamin D is good for the brain, as it also prevents the onset of neuro-degenerative diseases like Alzheimer’s, and Parkinson’s.
Vitamin D is also essential for the skeletal system because it promotes the absorption and storage of calcium and phosphorus in the bones, contributes to bone formation, and keeps bones strong and healthy, preventing fractures and osteoporosis. In addition, vitamin D is good for the muscles, as it improves muscle tone and muscle strength. Vitamin D stimulates the immune system, helps prevent infections, and lowers inflammation. It can also prevent autoimmune diseases. Some studies even show that vitamin D can lower the risk of developing tumors.
Furthermore, recent studies show that vitamin D is beneficial for the cardiovascular system because it helps lower blood pressure and reduce the risk of cardiovascular diseases. It is also useful in combating type 2 diabetes, since it is involved in the synthesis of insulin. Vitamin D also appears to have an effect on weight loss because it not only promotes the production of leptin, which increases satiety after meals, but also lowers the concentration of cytokines, which cause an increase in fat cells. Vitamin D also helps keep a healthy epidermis.
SOURCES OF VITAMIN D
The main source of vitamin D for our body is sunlight, which is synthesized by our skin when exposed to UV rays. 80% of Vitamin D3, specifically, is assimilated through the epidermis. Outdoor sunlight exposure to the face, arms, and hands is what our body needs, however, exposure to sunlight through glass or windows is not enough because this shields sunrays. The exposure time varies according to skin type, season, and latitude. During the summer, 15 minutes a day is enough; in winter up to 30 minutes. Although sun creams reduce the effectiveness of UV rays, and thus the assimilation of vitamin D, experts still recommend using adequate protection, especially in the peak hours of the day to avoid serious skin problems.
OTHER SOURCES OF VITAMIN D
Vitamin D is also introduced into our body through food, but only to a minimum (20%). Products of animal origin contain more vitamin D in the form of D3. Vitamin D is mainly found in oily fish (salmon, tuna, mackerel, sardines, herring, anchovies, etc.), but also in swordfish, trout and shellfish. Additionally, in egg yolk and dairy products (especially yogurt). In vegetables, whole grains, nuts (almonds, walnuts), mushrooms (maitake, shitake, chanterelle, champignon( porcini), beans, and leafy greens (spinach, chard, chicory, kale) vitamin D is found in its D2 form. Some plant based milks are also fortified with vitamin D, such as soy, coconut, almond, rice milk.
VITMAIN D REQUIREMENTS
The daily requirement of vitamin D should be 15 mcg for children, teenagers, adults, during pregnancy and while breastfeeding, and 20 mcg for older adults. In the case of vitamin D deficiency, it is vital to consume enough amounts through the diet, as well as with supplements (cod and liver oil) or fortified foods, and with adequate sun exposure.
SOURCES
