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Vitamin D: how much per day?

Paul Hummel Last reviewed June 10, 2026 5 min read
Vitamin D: how much per day?
Quick answer

When the body can't make its own, the German Nutrition Society (DGE) recommends a daily intake of 20 µg (800 IU) of vitamin D. The EFSA sets the safe upper limit at 100 µg (4,000 IU) per day.

What is vitamin D?

Vitamin D is a fat-soluble prohormone that the body can produce in the skin given enough UVB radiation. From October to March, however, sunlight in Central Europe is too weak for adequate self-synthesis. Diet alone (oily fish, egg yolk, mushrooms) also makes it hard to cover the requirement.

Chart: Vitamin D: need, limit & sources

Supply status in Germany

The National Nutrition Survey II by the Max Rubner Institute (2008) found that around 82% of men and 91% of women in Germany don't reach the German Nutrition Society (DGE) reference value of 20 µg (800 IU) of vitamin D per day through diet alone. Based on the DEGS1 study, the Robert Koch Institute (RKI, 2016) reports that around 30% of adults in Germany have a vitamin D deficiency (serum level < 30 nmol/l), with a seasonal rise in winter.

Official intake recommendations and safety

When endogenous synthesis is lacking, the DGE recommends a daily intake of 20 µg (800 IU) of vitamin D. Germany's Federal Institute for Risk Assessment (BfR, 2021) classifies daily supplementation of up to 20 µg (800 IU) as safe. The European Food Safety Authority (EFSA, 2012) sets the tolerable upper limit at 100 µg (4,000 IU) per day for adults.

For individual questions about your vitamin D status, seek professional advice. If you take high doses long term, your serum level should be monitored by a doctor.

Food sources

The richest dietary vitamin D sources are oily sea fish (herring: approx. 25 µg/100 g, salmon: approx. 16 µg/100 g), egg yolk (approx. 2–3 µg per egg), and foods fortified with vitamin D. Because dietary intake often isn't enough in Central Europe, supplementation — especially during the winter months — is a common option.

Vitamin D and muscle function

In a systematic review and meta-analysis, Beaudart et al. (2014) evaluated 30 randomized controlled trials on the effect of vitamin D supplementation on skeletal muscle. They observed a small positive overall effect on global muscle strength, which was most pronounced in people with a baseline 25-hydroxyvitamin D level below 30 nmol/l. In this analysis, supplementation showed no significant effect on muscle mass or muscle power.

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Related questions

Sources

  1. German Nutrition Society (DGE) (2012). Vitamin D — Reference Values for Nutrient Intake. DGE
  2. Robert Koch Institute (2016). Vitamin D status in Germany — DEGS1. Journal of Health Monitoring, 1(2). RKI
  3. EFSA (2012). Scientific Opinion on the Tolerable Upper Intake Level of Vitamin D. EFSA Journal, 10(7), 2813. EFSA
  4. Max Rubner Institute (2008). National Nutrition Survey II — Results Report Part 2. BMEL
  5. Beaudart, C., et al. (2014). The Effects of Vitamin D on Skeletal Muscle Strength, Muscle Mass, and Muscle Power: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Journal of Clinical Endocrinology & Metabolism, 99(11). PubMed
A note on supplements: supplements are no substitute for a balanced diet, and whether one makes sense depends on your individual situation. This content is for general informational purposes only and is not medical, nutritional, or therapeutic advice. If you have a medical condition, are pregnant, take medication, or are unsure, seek professional advice.