What is the controversy with taking vitamins

Vitamin D

Many wonder whether you can consume too much vitamin D - the answer is: yes, you can overdose. Vitamin D is fat-soluble and is stored in fat and muscle tissue. Anyone who now also takes vitamin D in high doses as a preparation risks an acute or creeping vitamin D overdose. Poisoning (intoxication) occurs. The levels of calcium in the blood increase and hypercalcaemia may develop.

A vitamin D overdose can manifest itself through these symptoms:

  • fatigue
  • Muscle weakness
  • Nausea, vomiting
  • Constipation or diarrhea
  • Stomach cramps
  • Arrhythmia
  • Kidney: kidney stones, calcification of the kidneys, decrease in kidney function

So vitamin D can also have some (serious) side effects. Therefore, always find out from your doctor whether you really need a vitamin supplement.

Vitamin D: when is too much?

The European Food Safety Authority (EFSA) puts the maximum acceptable level for vitamin D at 100 µg per day. If adults and children from the age of eleven take in up to this amount of vitamin D daily, no health impairments are to be expected according to current scientific knowledge. However, all vitamin D sources from which a person takes the vitamin are included in the UL value: vitamin D supplements, fortified foods and the normal diet.

The Federal Institute for Risk Assessment (BfR) considers the daily intake of vitamin D preparations with doses of 50 µg or 100 µg to be unnecessary from a nutritional point of view. Occasional consumption of such high-dose preparations is unlikely to have any adverse effects on health. However, according to studies, long-term and daily intake could mean an increased health risk. An overdose of vitamin D through diet and plenty of sun is not possible.

How quickly does vitamin D break down?

The body does not simply excrete or break down excess vitamin D, but stores it for a few months in adipose tissue and muscles, and in small amounts in the liver. So he can access the stock if necessary.

Vitamin D is bound to proteins in the blood and then transported to the liver. There it is chemically converted and then reaches the kidneys, where another chemical step takes place. Only then does the biologically effective calcitriol arise. It only has a short half-life of about four to six hours. Calcidiol (25-hydroxy-vitamin D) in plasma, on the other hand, has a half-life of around 15 days. It is considered a storage form of vitamin D, which is why laboratories usually determine the 25-hydroxy vitamin D. This can also be used to determine whether the vitamin D value is too high or too low.