Most people get the bulk of their vitamin D from sunlight, not from food. Your skin makes vitamin D when sunlight falls on it. That is why the Dutch advice on vitamin D depends on your age, your skin and how much time you spend outside.
The advice for women over 50
The Voedingscentrum, following the Health Council of the Netherlands, advises the following extra vitamin D per day:
- Women aged 50 to 69: 10 micrograms (µg) a day.
- Everyone aged 70 and older: 20 µg a day.
- People aged 4 to 69 who are rarely outside during the day, or who cover their face when outside: 10 µg a day.
- People aged 4 to 69 with a tinted or dark skin: 10 µg a day.
This advice comes on top of what you get from food and sunlight. It applies to everyone in these groups, not only to people with a known shortage.
Sunlight
For people who do not take a supplement, the Voedingscentrum advises spending 15 to 30 minutes outside every day between 11:00 and 15:00, with at least your face and hands uncovered. In practice, many women over 50 do not manage that every day, and in winter the sun is much weaker. That is one reason the advice for this age group is a supplement rather than more time outside.
Food
Few foods contain much vitamin D. Oily fish such as salmon, trout and herring are the richest sources. Meat, eggs and dairy contain smaller amounts. In the Netherlands, vitamin D is added to margarine, half-fat margarine and liquid cooking fat. Oils do not contain it.
What vitamin D does
Vitamin D contributes to the maintenance of normal bones, to the normal absorption and use of calcium, and to the maintenance of normal muscle function. It also contributes to the normal function of the immune system.
How much is too much?
The European Food Safety Authority (EFSA) has set a safe upper level of 100 µg of vitamin D per day for adults, from all sources together. If you take more than one supplement, add up the vitamin D in each. Do not take more than the dose on the label, and check with your doctor if you already get vitamin D on prescription.
Our product
Bone gives you 25 µg of vitamin D3 and 20 µg of vitamin K2 in one drop a day. That is more than the 10 or 20 µg in the Dutch advice, and well below the EFSA upper level of 100 µg. If you also take Daily, which contains 5 µg of vitamin D, you get 30 µg a day in total. If you would rather take exactly the advised amount, choose a 10 or 20 µg supplement. Vitamin K affects blood clotting, so if you use blood-thinning medication, check with your doctor first.
Sources
- Voedingscentrum, Vitamine D (folder, 2026).
- Voedingscentrum, Factsheet suppletieadviezen.
- EFSA, Scientific opinion on the tolerable upper intake level of vitamin D (2023).
- EU Register of nutrition and health claims (Regulation (EU) No 432/2012).
