Vitamin D is a very special vitamin, which was identified in the early twentieth century. Apart from its fundamental role in protecting and strengthening the bones, it has a unique aspect as a nutrient: it can be synthesized by the human body through sunlight. This facilitates its absorption in hot and sunny climates and tends to make its lack evident wherever the climate is cold and the sun doesn’t rise. This ubiquity and apparent simple way of contributing to our general wellbeing also complicate the fact of establishing the recommended minimum daily doses.
Vitamin D (also called calciferol) belongs to the group of fat-soluble vitamins, that is, those that accumulate in cells, and therefore must be consumed with caution. It’s made up of two forms, Vitamin D2 and Vitamin D3. The former (ergocalciferol) is usually created in human tissue and is sometimes added to food.
Vitamin D3 (cholecalciferol) is synthesized in the skin and can also be incorporated into your diet by consuming animal foods. These two vitamins can be manufactured, and it appears that their healing properties for the corresponding deficiencies are the same. Both are biologically inactive until two enzymatic reactions are carried out by hydroxylation, the first in the liver and the second in the kidneys.
Within any diet, there are a number of nutrients that contain vitamin D, including fatty fish such as tuna, salmon and mackerel, different kinds of cheese, egg yolks, as well as various kinds of fungi and mushrooms. Keep in mind that this vitamin accumulates, and can cause toxicity when we abuse of supplementation. Signs of intoxication include poor appetite, fatigue, weight loss, nausea, and vomiting. Too much vitamin D can also cause disorientation and major heart rhythm problems.
Read the full article on our July issue!