Vitamin D is mainly synthesised in the skin under the influence of ultraviolet UVB rays, but is also supplied with food.
It is essential for the proper functioning of the skeletal system, as it enhances the absorption of calcium in the intestines, facilitates transport and enables its incorporation into the bones, regulates the calcium-phosphate balance and strengthens the immune system.
It also regulates energy processes in the body, affects the parathyroid glands, the nervous, muscular, immune and endocrine systems.
Its demand may be increased in large cities with polluted air, where its cutaneous synthesis decreases, in people who spend most of their time indoors and use sunscreens, in addition to people who take anticonvulsant drugs, alcoholics or drug addicts, but also in the elderly due to impaired cutaneous synthesis, reduced absorption or metabolism of this vitamin. Vitamin D deficiencies are quite common.
Vitamin D
