How Vitamin D Plays a Role in Your Health
We grow up with the knowledge that vitamins are healthy. That we should eat fresh vegetables and fruit so that we are supplied with all the essential vitamins.
It often seems, especially in some ads, as if vitamin C is the most important vitamin of all, and the rest is negligible. But often, this is a very simplified and reduced view of things.
Many people hear about vitamin D and how it is produced in the human skin when exposed to sunlight. It is the only vitamin in the human body made in this way — a nutrient that the body can make itself!
It also influences the processing of the two neurotransmitters dopamine and norepinephrine, which are also essential for our mood.
As soon as the vitamin D level is low due to the lack of sunlight, our serotonin level gets out of balance. Therefore, if you have a serotonin deficiency in the winter months, vitamin D should be the first thing on your mind.
Vitamin D can be taken externally with food or medicine.
Vitamins D2 (ergocalciferol) and D3 (cholecalciferol) are particularly important for humans. They are precursors of hormones rather than vitamins. Both vitamins are found in animal foods and are formed in the human skin. For this, however, they need sunlight.
The sunlight helps the body make an inactive precursor of vitamin D available in the skin, converted into the active vitamin D3 hormone calcitriol in the cells as needed.
Vitamin D3 is formed in the body with the help of UVB rays in the skin.
Since we can only absorb about 20% of our daily vitamin D requirement through food, sunlight is essential. Our body can produce up to 20,000 IU of vitamin D on a very sunny day.
The body’s own synthesis of vitamin D passes through several stages before the vitamin is available as bioactive vitamin D3:
- The vitamin’s precursor is cholesterol, which enters the skin with lipoproteins’ help.
- The cholesterol is then converted to 7-dehydrocholesterol.
- Cholecalciferol is then obtained when the skin is exposed to sunlight.
Next, vitamin D3 is hydroxylated in the liver and converted to calcidiol — the storage form of vitamin D. The conversion from calcidiol to calcitriol then follows in the kidney.
Calcitriol has a regulating function in the balance of calcium-phosphate metabolism. The most important organs are the kidneys for recovery, the gut for absorption, the bones and teeth for storage, and bone density.
The more intensive the sunbathing and the stronger the solar radiation, the more vitamin D3 the body can form and the higher the vitamin D level. However, vitamin D formation only takes place up to a certain limit. Hence, an overdose of vitamin D from the sun is impossible.
Most nutrients rarely act individually but in combination with other vitamins or minerals. These so-called cofactors are not absolutely necessary, but they can support vitamin D synthesis and compensate for an undersupply.
In interaction with magnesium, there is a significant synergistic effect. Magnesium favours the activation of D3, vs. D3 promotes the absorption of magnesium in the gut.
Vitamin D is often associated with vitamin K. Vitamin K1 can be found in green leafy vegetables, eggs, and whole-grain products, so deficiency is extremely rare. The other types of K2 can be found in fermented foods and liver meat.
Furthermore, vitamin D3 supports the immune system and plays a role in cell growth.
This means that almost every cell needs vitamin D: kidneys, liver, muscles, nerves, skin, glands, immune cells.
Now it becomes understandable why sun therapy was used so successfully in ancient times.
Basically, UVB rays have a much better effect than food or supplements.
In comparison: With the help of UVB light, the body can produce up to 20,000 IU of vitamin D. However, 100 grams of eel, kipper, or herring only provide a dose of 1,000 to 3,500 IU of vitamin D, which is why the risk of an undersupply is particularly high here.
Although the body can store vitamin D, the body’s own reserves are quickly depleted if there is no exposure to sunlight for a more extended period of time. This is especially the case in winter when sunlight is scarce, and most of the skin is covered with clothing.
Note that people with more melanin, who have dark skin, get less vitamin D production compared to white-coloured people. On the contrary, people with dark skin are less prone to cancer from UV rays of sunlight due to melanin.
The need for vitamin D is increased in people who drink a lot of tea and coffee.
Vitamin D helps your body absorb calcium. Calcium is one of the main building blocks of bone and has a role in nerve, muscle, and immune systems. A lack of vitamin D can lead to bone diseases such as osteoporosis or rickets.
However, you have good intake levels of calcium and vitamin D, then there is little reason for concern about caffeine drinking on your bones, although it could raise your blood pressure or increase your heart rate.
In food, vitamin D can be found in fatty fish, milk, butter, eggs, and mushrooms. Still, the amounts are small. There are dietary supplements as tablets, capsules, in oil, also enriched with K2.
If you have your vitamin D3 level every now and then, then you are on the safe side. Values between 40–60 ng/ml indicate a sufficient supply. Keep in mind that according to studies, up to 75% of the population is undersupplied during the winter months. Hardly anyone knows this.
Before you decide to take vitamin D, you should have your vitamin D level measured. Otherwise, you might take far too little and therefore feel no effect. Or you might take much more than necessary, which would, in turn, put unnecessary strain on your body.
Therefore, you should only take as much vitamin D as you personally need. To find out the right dose for you, measure your current vitamin D level. This can be done by your family doctor.
Disclaimer: The article isn’t medical advice. Author is not a medical doctor. The information is for educational purposes only. It is not meant to diagnose or treat any medical conditions.
