Itamine D is one of the most important substances responsible for human health. It regulates more than a thousand physiological processes in the body, including providing DNA regeneration processes. Lack of vitamin D is associated with impaired immunity and an increased risk of infections.
Unfortunately, more than half of the inhabitants of Russia suffer from a chronic lack of this vitamin. The reason is that you need to be in the sun for 10-15 minutes every day to develop your daily intake of vitamin D – or take regular supplements.
Vitamin D – what is it?
Vitamin D is a group of fat-soluble vitamins that support the proper functioning of the immune system. The substance was discovered in 1922, becoming the fourth vitamin known to science – due to which it received the designation “D”.
Primarily, vitamin D is needed by the body for the absorption of calcium and phosphorus – helping to maintain bone strength and ensuring the transmission of impulses between cells (for example, for muscle contractions). In addition, in the body of men, it is involved in the synthesis of testosterone.
Studies show that not getting enough vitamin D daily increases the risk of dying from heart disease by 35% and increases the risk of cancer by 14%. In addition, chronic vitamin deficiency is associated with seasonal depression
- low testosterone in men – symptoms
- osteoporosis in women – how to prevent?
Daily norms
The body’s daily requirement for vitamin D ranges from 10 micrograms for children (this dose can be referred to as 400 IU or 400 IU) to 15 micrograms per day for adults (which is equivalent to 600 IU). For older people over 70, the daily intake of this vitamin is about 20 mcg (or 800 IU).
Note that, being fat-soluble, vitamin D is able to accumulate in the body – in other words, its excessive consumption is dangerous because it causes intoxication. The maximum safe daily intake is 1,000 to 3,000 IU for children and 4,000 IU for adults ³ .
Deficiency symptoms
Vitamin D deficiency is associated with a drop in immunity, chronic fatigue, impaired growth in children, and weakening of the strength of bones and teeth in adults. In addition, non-receipt of the daily intake of the vitamin can lead to a deterioration in the quality of hair and nails.
Among other things, vitamin D controls the conversion of tryptophan to serotonin. In the brain, serotonin is responsible for good mood, normal memory function, impulse control, and the ability to prioritize problem solving – as well as other cognitive functions.
If taking steroids, don’t forget the aromatase inhibitor tamoxifen to avoid aromatization.
How to fill the gap?
There are three main ways of providing the body with vitamin D – through synthesis in the surface layers of the skin under direct exposure to ultraviolet radiation (that is, when sunbathing), the use of vitamin D in food, as well as the use of supplements and vitamins.
To get the daily intake of vitamin D, you need to be in the sun for 10-15 minutes (the face, arms, legs and back should be exposed to the sun’s rays) – however, this condition is practically impossible in winter and autumn conditions. Among other things, some people are unable to synthesize vitamin D even in direct sunlight.
Vitamin D content in foods
The difficulty of obtaining vitamin D from food is due to the fact that a very limited amount of natural products contain it in the composition. In most cases, it is very expensive and difficult to cover the body’s needs for this vitamin solely with the help of nutrition.
In some countries, products are additionally irradiated with ultraviolet light to increase the content of vitamin D. First of all, mushrooms and dairy products are processed – a glass of such milk will contain about 100 IU of vitamin D. Unfortunately, this practice does not exist in Russia.
Separately, it should be noted that a spoonful of fish oil (for example, cod liver oil) contains up to 1400 IU of vitamin D, which is equivalent to 230% of the daily value. Since this vitamin can cause overdose and intoxication, it is necessary to avoid the use of several vitamin complexes at once.
// Foods rich in vitamin D:
| Food product | Vitamin D content per 100 g | Percentage of Daily Value |
| Sardines in oil | 500 IU | 83% |
| Catfish | 440 IU | 73% |
| Salmon, mackerel | 340-360 IU | 58% |
| Canned tuna | 235 IU | 40% |
| Egg | 30 IU | five% |
