Are vitamin D supplements good for you?

Vitamin D: what does the sun vitamin really do?

Food supplements

12/20/18 (ams). Advertisements for vitamin D work, but vitamin D tablets don't work for most people. What is the truth about the vitamin D hype? Anja Debrodt, a doctor in the AOK Federal Association, lists the facts.

Especially in winter, vitamin D is increasingly being touted as an all-rounder. The marketing is working: Pharmacies alone sold vitamin D preparations for around 177 million euros in 2017. And Amazon is promoting a vitamin D product as a bestseller in 2018. Every year in winter, many people ask themselves the question: Do I need more of the "sun vitamin" or not? "Vitamin D tablets are of no use to most people," says doctor Debrodt. "And very few of them suffer from a real vitamin D deficiency."

As part of an AOK fact box, the current study situation has been reviewed with the result that additional vitamin D - beyond the normal diet - can prevent neither cancer nor cardiovascular diseases. However, that does not mean that vitamin D is unimportant to the body. "It plays a key role in bone metabolism," says Debrodt. "It helps the body absorb calcium from food and thus hardens bones and teeth." It is also involved in other metabolic processes and has a positive effect on muscle strength. Another fact: a real deficiency in vitamin D has serious consequences. Bone softening can occur, called rickets in infants and young children, and osteomalacia in adults. "These diseases can actually be treated well with vitamin D tablets," says Debrodt. In addition, a vitamin D deficiency in the elderly is a risk factor for osteoporosis. The bone density decreases and there are more frequent bone fractures.

Ready-to-broadcast radio o-tones with Anja Debrodt, doctor in the AOK Federal Association

Serious deficiency rarely occurs

According to a study by the Robert Koch Institute (RKI), only just under 40 percent of adults in Germany achieve an optimal vitamin D value. But a serious vitamin D deficiency rarely occurs. So what about the people whose values ​​are not extremely low, but also not optimal? Should They Take Extra Vitamin D? AOK expert Debrodt: "Only when two conditions are met. First, a doctor's blood test should have confirmed that the vitamin D level is too low. And then those affected should first try to replenish the vitamin D stores naturally." The main part is made up of the body itself with the help of UV light from the sun. Therefore, the general recommendation is to expose your face, hands and arms to the sun for a short time, at least from March to October two to three times a week, without sunscreen and without sunscreen (use sunscreen in good time). The body stores the fat-soluble vitamin in fat and muscle tissue as well as in the liver and can use the supplies in winter. Even in the winter months, the body produces some vitamin D if you go for a walk outside for 20 to 30 minutes with a clear face and without gloves. You can also help with food: A few foods contain significant amounts of vitamin D. However, depending on age, lifestyle, skin type and skin thickness, the body does not manage to produce enough vitamin D for all people.

It can therefore make sense to take tablets for the following risk groups:

  • Older people from around 70 years, because the self-production of vitamin D decreases with age. In some cases, the skin then only produces half as much vitamin D as in earlier years of life.
  • Seniors in need of care who rarely leave the house or who live in a care facility.
  • Even younger people who suffer from chronic gastrointestinal, liver or kidney disease or who are taking medication that impair the vitamin D metabolism (for example medication for epilepsy or cancer).
  • People with darker skin tone; because the increased melanin content of the skin keeps the UVB rays from the sun stronger.
  • People who veil themselves for cultural or religious reasons.
  • Baby; Because the vitamin D content in breast milk is low and the baby's skin must not be exposed to the sun due to the fact that protective mechanisms have not yet developed. That is why they are prescribed special vitamin D supplements by the pediatrician as part of their general preventive care.


Filling up vitamin D stores

  • Go out every day! Expose face, arms and hands to the sun for a few minutes without protection. Caution: avoid sunburn in summer or on vacation, so use a sunscreen in good time. But vitamin D is also formed in the shade and when the sky is overcast. Even in winter. To do this, briefly remove the gloves.
  • Consume foods containing vitamin D! Above all fatty sea fish such as herring, salmon or sardines. Warning: wild salmon contains four times as much vitamin D as farmed salmon! Vitamin D suppliers are also porcini mushrooms and mushrooms, veal, margarine and eggs. The front runner is cod liver oil, which tastes quite penetrating and which is why so many children used to have to swallow it every day.

The same applies to osteoporosis: only those who do not achieve the necessary vitamin D dose with sunlight and nutrition can take a vitamin D preparation to prevent osteoporosis or - in combination with calcium - to support osteoporosis treatment.

In any case, the intake of vitamin D should always be discussed with the family doctor. Because too much vitamin D can also be harmful. Excessive amounts of vitamin D increase the level of calcium in the blood. Initially, this can lead to increased urine output, thirst and nausea. Since calcium is deposited in the kidneys, there is a long-term risk of kidney calcification with the risk of acute or chronic kidney failure. The recommended dose is 800 International Units (IU) per day. "If a doctor prescribes higher doses of vitamin D for a short time, the blood values ​​should be monitored," says Debrodt.

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To the ams guide 12/18

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