Ten micrograms, twenty micrograms, or that high dose your friend takes? In the supermarket and the chemist there are dozens of vitamin D pots with varying doses, and the numbers on the box probably mean little to you. How much do you actually need?
My advice: first build a base with the recommended maintenance dose. High doses only make sense with a proven deficiency, not as a general precaution.
How much vitamin D do you need per day?
The Gezondheidsraad (Dutch Health Council) gives clear supplement advice per group. These are maintenance doses, meant to prevent a deficiency, not to treat an existing one. The table below lists the advice.
| Group | Advice per day | Period |
|---|---|---|
| Children 0 to 4 years | 10 ug (400 IU) | All year |
| Adults 4 to 70 years, light skin | 10 ug | If you are outdoors too little |
| Women 50+ and men 70+ | 20 ug (800 IU) | All year |
| Dark skin or covering clothing | 10 to 25 ug | All year |
| Pregnant women | 10 ug | Whole pregnancy |
With a proven deficiency, your doctor may temporarily prescribe a higher loading dose. You do not do that on your own, because with vitamin D more is emphatically not better.
Which vitamin D is best?
Choose vitamin D3 (cholecalciferol) over D2 (ergocalciferol). D3 is absorbed better and keeps your level more stable. The form (drops, capsules or tablets) makes little difference for effectiveness, so choose what suits you. Drops are handy for children or if swallowing is difficult.
Daily or weekly: does it matter?
Many supplements offer a daily dose, but you also find high-dose capsules taken once a week. Because vitamin D is stored in your body, a weekly dose that adds up to the same amount works out almost the same. The practical difference is habit: a daily moment tied to your evening meal is harder to forget than a single weekly appointment. Avoid extreme mega-doses in one go, because they are not needed and only increase the chance of too much.
Where do you find vitamin D?
Vitamin D occurs in few foods, and rarely in large amounts. Oily fish is the richest source. Food alone is insufficient for most people, certainly in winter.
- Oily fish: salmon, mackerel, herring (5 to 10 ug per portion)
- Eggs: 1 to 2 ug per egg
- Fortified products: some margarines, cooking fats and dairy
When and how do you take vitamin D?
Take vitamin D with a meal containing some fat, because it is fat-soluble and absorbed better that way. The time of day matters little, so pick a fixed moment so you do not forget. Your level is lowest at the end of winter, which is why taking it year-round is preferable to only in summer.
Vitamin D and calcium
Vitamin D has a fixed partner: calcium. Vitamin D enables you to absorb calcium from your food, which is what makes it important for your bones. That is why the Voedingscentrum advises, alongside vitamin D supplementation, to ensure enough calcium from dairy, vegetables and legumes. If you take vitamin D in a higher dose on your doctor's advice, that may also cover your calcium need. You do not just take a separate high-dose calcium supplement, because too much calcium also has drawbacks.
Can you take too much vitamin D?
Yes, but it is rare at normal doses. Vitamin D is fat-soluble and stored in your body. With prolonged intake above 100 ug per day, hypervitaminosis D can develop, with the risk of too much calcium in your blood. Symptoms are then nausea, vomiting and confusion. Stick to the recommended doses and consult your doctor if in doubt.
Frequently asked questions
Do I need a blood test before taking vitamin D?
For most people, supplementation following the Health Council advice is safe without a prior test. A test is useful if you have symptoms, belong to a high-risk group, or want to check whether your dose is enough.
How quickly does vitamin D supplementation work?
Your level rises gradually over weeks. With a large deficiency it can take 2 to 3 months before your value is sufficient again.
Does a tanning bed help?
No. Tanning beds mainly emit UVA radiation, while your skin needs UVB. They are discouraged because of the skin cancer risk.
Checking whether your dose is right
If you doubt whether your current dose is enough, have your vitamin D level checked. If you have symptoms that fit a deficiency, first read vitamin D deficiency: symptoms and testing and how serious a deficiency is. If you want to combine vitamin D with a broader picture, the basic health checkup measures your key values at once. This article is part of our vitamin deficiency overview.
Every blood test result at Vitalcheck includes a professional assessment by a BIG-registered doctor. A blood value is not a diagnosis: always discuss symptoms and treatment decisions with your GP.
Sources
- Gezondheidsraad. Dietary reference values for vitamins and minerals. 2018.
- RIVM. Vitamin D deficiency in winter among the Dutch population. 2023.
- Voedingscentrum. Vitamin D. Accessed 2026.
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