Although it is called a vitamin, it is a leading hormone and has been produced by life forms for 750 years. Most animals exposed to sunlight have the capacity to make vitamin D. In humans, vitamin D is of great importance for healthy body development, growth, and maintenance that begins with pregnancy in the womb and continues throughout life.
The best source of vitamin D is the sun, but what time is the sun? Here it is necessary to know the distinction well. When ultraviolet B (UVB) rays of the sun come into contact with our skin, it synthesizes cholecalciferol, a vitamin D precursor, from cholesterol. On the contrary, ultraviolet A (UVA) rays break down the cholecalciferol synthesized in the skin, that is, it disrupts the vitamin D synthesis. UVB rays are at the wavelengths the sun comes from at a right angle. Also, a study conducted in 2007 showed that the regions in the world where only the sun is sufficient for UVB intake, ie vitamin D synthesis, are the Equator Region, which is between the 37th north parallel and 37th south parallel. This parallels between 36-42 Located in northern Turkey showed just can not produce enough vitamin D for the sun.
What are the functions of vitamin D in the body?
Vitamin D is one of the hormones that affect the organism of human beings throughout their life. The effects of vitamin D on regulating bone health by regulating only calcium metabolism in the body are just like the part of an iceberg above the water. In fact, besides calcium metabolism, it has very important effects on cell differentiation, the immune system, prevention of infection and/or inflammations, and insulin secretion. In recent epidemiological studies, it has been reported that low vitamin D level increases cancer incidence and cardiovascular mortality, and is associated with autoimmune diseases such as diabetes and multiple sclerosis. Vitamin D ensures that the bone is hardened with calcium. This process is called mineralization. Vitamin D deficiency causes rickets in childhood and osteomalacia (bone resorption) in adulthood.
In rickets, even if the calcium is very little, the bone formation does not stop and collagen and other proteins required for bone formation continue to be made. However, since the mineralization is insufficient, the bones do not harden and become elastic, suitable for bending. If vitamin D deficiency in a rickety child causes a serious decrease in blood calcium, it causes tremors called tetany, hand and foot cramps, painful spasms in the pharynx, and nausea. In more advanced cases, breathing difficulties and the patient may suffer seizures and loss.
In osteomalacia, the childhood period has passed and the bones have previously taken their necessary form, since vitamin D deficiency causes calcium deficiency, the bones discharge their own calcium into the blood and the bones become susceptible to fracture.
Things to know about vitamin D
– 10 thousand to 25 thousand IU of vitamin D is synthesized in the body of a person who sunbathes for about 30 minutes at noon.
– A person sunbathing in a swimsuit is given 20 minutes of maximum vitamin D After the production reaches its maximum, no more active vitamin D metabolites are synthesized. So more sunbathing doesn’t mean synthesizing more vitamin D.
– Cholecalciferol, which is synthesized in the skin when sunbathing properly, reaches the surface of the skin with the secretions of the sebaceous glands and is absorbed from the skin again within 48 hours and passes into the blood. If it is washed with shampoo or soap and removed from the body before it is absorbed from the skin, vitamin D synthesis does not occur. After sunbathing, it is recommended to take a shower with warm water, without soaping the sun-exposed areas such as the face, arms, shoulders, and legs.
Black people with a thick pigment layer need to stay in the sun 4-5 times more to synthesize the same amount of vitamin D.
– Congenital deficiency of the receptor causes a very rare disease called vitamin D resistant rickets Type II.
– High amount of active vitamin A (retinoic acid) reduces the beneficial effects of vitamin D. More of the herbal precursors of vitamin A (beta-carotene) do not have any harm.