Vitamin D is one of the few vitamins that our body can produce itself with the help of sunlight. Especially in the darker months, the sun in Germany is often not enough – and a deficiency remains unnoticed for a long time because the symptoms are non-specific. This article explains how to recognize a vitamin D deficiency, which values are considered normal, and how to determine your status.
Why Vitamin D is so important
Vitamin D regulates the absorption of calcium and phosphate and is therefore crucial for stable bones and teeth. It also plays a role in muscle strength and the immune system. Evaluations by the Robert Koch Institute show that a significant portion of the population in Germany does not achieve the recommended vitamin D supply – especially in the winter months.
Typical symptoms of a vitamin D deficiency
A deficiency develops gradually.Commonly reported signs are:
- persistent fatigue and lack of drive
- frequent infections
- muscle weakness and muscle pain
- bone and joint pain
- low mood, especially in the winter months
These symptoms are non-specific and can have many causes. Only a measurement of the vitamin D level in the blood provides clarity. You can find more background on our page Vitamin D – the key to your health.
What are normal vitamin D levels?
The storage form 25-OH-vitamin D is measured, usually in nanograms per milliliter (ng/ml) or nanomoles per liter (nmol/l).For orientation:
- under 12 ng/ml (30 nmol/l): significant deficiency
- 12–20 ng/ml (30–50 nmol/l): insufficient supply
- from 20 ng/ml (50 nmol/l): adequate supply
The assessment should always be made in the overall medical context. The German Nutrition Society (DGE) provides further intake recommendations.
Compensating for a vitamin D deficiency
First and foremost is sunlight: In summer, often 10–20 minutes daily on the face and forearms is sufficient. Fatty sea fish, eggs, and fortified foods contribute through diet. If this is not enough, targeted supplementation can be useful – ideally based on a measured value to avoid over- or under-dosing.
Determine Vitamin D status easily from home
With the Vitamin D Check from Probatix , you can conveniently measure your level from home; the evaluation is carried out in an accredited specialist laboratory. If you want a broader overview, you will find more suitable tests in our Nutrients category.
Frequently Asked Questions
How can you tell if you have a vitamin D deficiency?
Typical symptoms include fatigue, frequent infections, muscle weakness, and bone and joint discomfort. Since the signs are non-specific, only a blood test can confirm the diagnosis.
What vitamin D level is too low?
Levels below 12 ng/ml (30 nmol/l) are considered a significant deficiency, 12–20 ng/ml as insufficient supply.
When should you test for vitamin D?
Testing is particularly advisable in the winter months and in cases of persistent fatigue or increased risk (little sunlight, darker skin type, older age).
This post is for general information purposes and does not replace medical advice. If you have persistent symptoms, please consult your doctor.
