Vitamin D – Why you need more than you’re told

The underestimated superpower from sunlight

Vitamin D has long been more than just the "classic bone vitamin." It influences our immune system, protects the heart and brain, can help with depression—and yes, can even reduce the risk of cancer. But while science has long since learned more, official recommendations in Germany and Switzerland remain surprisingly conservative. Why, exactly?

What is currently recommended – and why it is not enough

The German Nutrition Society (DGE) recommends that adults take 800 IU (International Units) of vitamin D daily – based on the goal of preventing bone diseases such as osteoporosis.

But what about:

• Immune system?
• Inflammation?
• Cardiovascular risks?
• Neurological diseases?
• Cancer prevention?

👉 Much more is needed for all of this – say numerous international studies.

A look beyond the horizon

Comparison of international recommendations:

Country / Organization	Recommendation	upper limit
Germany / Switzerland	800 IU	4000 IU
Canada	4000–10,000 IU for risk groups	10,000 IU
USA (Endocrine Society)	Up to 10,000 IU considered safe	10,000 IU
EFSA (EU)	600 IU	4000 IU

Scientists like Prof. Holick and Vieth say: Up to 10,000 IU daily is not only safe – it is evolutionarily normal.

How much vitamin D do we really need?

In traditional cultures with plenty of sunlight, people achieve vitamin D levels of 40–60 ng/ml . Achieving this in Europe requires:

👉 5000–10,000 IU daily – especially in winter or when there is a lack of sun.

Numerous studies prove:

• No toxicity at 10,000 IU daily
• Significantly better immune defense
• Lower risk of diabetes, heart disease and autoimmune diseases
• Milder course of respiratory diseases – e.g., COVID-19

Conclusion: Official recommendations lag behind

Vitamin D is a true all-rounder for your health – but you need to consume it in sufficient quantities. The current 800 IU is enough for healthy bones – but not for optimal health .

What you can do:

✅ Have your vitamin D levels (25(OH)D) tested regularly
✅ Aim for values ​​between 40–60 ng/ml
✅ Use high-quality nutritional supplements – especially in winter
✅ Don’t be afraid of 5000–10,000 IU – as long as you check regularly