Vitamin D in the Netherlands and Europe: Who Is Advised to Supplement and What the Numbers Mean

It's October in the Netherlands. The sun has clocked off for the season, the drugstore shelf is full of vitamin D in two different units, and every bottle seems to be shouting a different number. Before you pick one, it helps to know whose number it is: the number on a pack, the number a health body publishes, and the number on a blood-test report are three different things.

Who actually needs a vitamin D supplement in the Netherlands or elsewhere in the EU? Fewer people than the shelf suggests, though some groups clearly do. For most healthy adults, sunshine between spring and autumn plus ordinary food does most of the work. The Netherlands' official advice names specific groups who should take a supplement all year (children aged 0 to 3, women aged 50 to 69, pregnant women, anyone aged 70 or older, and people with a darker skin or who rarely get outside). A routine blood test is not part of that advice, and the 2024 Endocrine Society guideline also suggests against routine testing in healthy people. The rest of this page explains where those numbers come from, so you can tell which category you fall into.

Why northern Europe is the question

Your skin makes vitamin D when ultraviolet B (UVB) light hits it. That is why the Gezondheidsraad (the Dutch Health Council) calls skin synthesis the main source of vitamin D in the Netherlands. In its 2012 advice, it says that for someone with a light skin who is regularly in the sun, roughly two thirds of the year's vitamin D comes from sunlight and a third from food (Gezondheidsraad, Evaluatie van de voedingsnormen voor vitamine D, 2012). The Voedingscentrum puts the winter problem in one line: in the Dutch winter months the sun stands too low to make vitamin D (Voedingscentrum, Vitamine D, read 8 October 2026).

Even the sunny season has fuzzy edges: sources draw its start and end in slightly different places.

• Source: Gezondheidsraad (2012); What it says about the sunny season: In Dutch conditions, skin can make vitamin D from March to November
• Source: Voedingscentrum (current page); What it says about the sunny season: Advises March to October: 15 to 30 minutes outdoors between 11:00 and 15:00, face and hands uncovered. It adds that the advice is not strictly black and white: more exposed skin or a longer stay outdoors makes more, and a long weekend outside can make up for indoor days
• Source: NHS (UK); What it says about the sunny season: From about late March or early April to the end of September most people can make what they need; between October and early March we do not make enough
• Source: EFSA (2016); What it says about the sunny season: Its reference values assume minimal skin synthesis; the underlying studies were done from October through April at latitudes above 40° N

The NHS and EFSA wording is from the NHS vitamin D page and EFSA and SACN's joint explanatory note. The practical reading: the dark months are real, but how much sun you actually catch depends on your habits. The Gezondheidsraad is fairly concrete about "too little sun": less than 15 to 30 minutes a day outdoors in high sun (11:00 to 15:00), with head and hands uncovered, doing everyday things. The Voedingscentrum's own sun advice, in the table above, is the same idea in a friendlier form.

Two other things change the picture. Skin tone: people with a darker skin make less vitamin D from the same everyday sun, and the Gezondheidsraad says a healthy diet cannot make up the difference, which is why supplements are advised for them. Age: for people aged 70 and over, the Council cites convincing trial evidence that 10 to 20 µg extra per day can reduce the risk of fractures, and sets a higher amount for that age group (more on that below).

How common is low vitamin D across Europe? A 2016 study by Cashman and colleagues in the American Journal of Clinical Nutrition standardised blood data from 14 population studies plus four earlier standardised ones (55,844 people in total). It found 13.0% of Europeans had 25(OH)D below 30 nmol/L on average across the year (17.7% in October to March, 8.3% in April to November), and 40.4% were below 50 nmol/L. Dark-skinned subgroups had three to 71 times the rate of the lower figure seen in white populations (Cashman et al., 2016). Notice that the "40 per cent deficient" figure that circulates is the result of choosing the 50 nmol/L line. It is not the same claim as "40 per cent have a clinical deficiency".

What the Dutch bodies recommend, by group

Here is what the official Dutch advice says; working out which row is yours is up to you. The Voedingscentrum's page (read 8 October 2026) lists these groups for a supplement:

• Group: Children aged 0 to 3; Vitamin D supplement per day: 10 µg
• Group: Ages 4 to 69 with a darker (tinted) skin; Vitamin D supplement per day: 10 µg
• Group: Ages 4 to 69 who are not outdoors much during the day; Vitamin D supplement per day: 10 µg
• Group: Women aged 50 to 69; Vitamin D supplement per day: 10 µg
• Group: Pregnant women; Vitamin D supplement per day: 10 µg
• Group: Everyone aged 70 or over; Vitamin D supplement per day: 20 µg

The same page gives a general recommended daily amount of 10 µg for everyone, with 20 µg only for people over 70. For context, 1 µg of vitamin D equals 40 IU, so 10 µg is 400 IU and 20 µg is 800 IU (the conversion is stated in the Gezondheidsraad advice).

The reasons the Voedingscentrum gives are specific to each group. Supplements in young children reduce the risk of rickets. In older adults a vitamin D supplement lowers the risk of falls and fractures. For pregnant women it names a lower risk of gestational diabetes and low birth weight. The Gezondheidsraad's 2012 advice is more cautious on pregnancy than the headline suggests: it says pregnant women do not seem to have a higher need, but that serious deficiency can harm the newborn and that about 10 per cent of fair-skinned pregnant women were deficient, so it advises all pregnant women to take 10 µg "to be on the safe side". The Voedingscentrum's current page keeps the 10 µg recommendation.

The Council's targets sit behind these amounts. For ages 4 to 70 it aimed for a blood level of at least 30 nmol/L all year round, and for people aged 70 and over at least 50 nmol/L, which is why the older group gets the larger 20 µg amount. It also said that fair-skinned adults who spend enough time in the sun and eat well do not need a supplement. The Council was explicit that some of its advice is precautionary ("for the sake of certainty"), notably for women aged 50 to 70 and for dark-skinned people, where evidence was thinner.

For a light-skinned man in his twenties or thirties who gets outside regularly, that table does not include him. That does not mean he has "enough". It means that the Dutch advice has not identified him as a group where supplementing is advised. If you work shifts, spend your days at a screen and your evenings at one too, or cover most of your skin outdoors, the "not outdoors much" row is the one to read twice.

On the clinical side, Thuisarts, the Dutch GPs' patient-information site, says it is almost never necessary to do blood tests for vitamin D, with rare cases such as treating osteoporosis with medication (Thuisarts, page updated 9 July 2026). Dutch rules and advice are not EU-wide, and bodies in other countries draw their lines elsewhere, so check your own country's advice if you live outside the Netherlands. The UK's SACN, for instance, uses a lower population target than EFSA (see the thresholds table below).

What food contributes

Food does some of the work, but it is not a big supplier. The Voedingscentrum says vitamin D occurs naturally in fatty fish such as herring and salmon, and in smaller amounts in meat and eggs. In the Netherlands it is also added to halvarine, margarine and liquid cooking fats, though not to oil. Its table of examples (read 8 October 2026) gives about 9.4 µg in a 100 g portion of cooked trout, 4.6 µg in 100 g of salmon, 0.9 µg in a boiled egg and 0.4 µg in the margarine on one slice of bread. Those are one-off examples rather than daily averages, but they show why the Gezondheidsraad's two-thirds sun and one-third food split leaves some groups short in the dark months. The Voedingscentrum's own advice is to eat the Schijf van Vijf way, with fatty fish, margarine or halvarine and liquid cooking fat in it, and to supplement only if you are in one of the groups above.

What EFSA says about amounts and upper limits

EFSA's numbers answer a different question from the Dutch ones. In 2016 EFSA set an Adequate Intake of 15 µg per day for adults and for children aged one to 17 (including pregnant and lactating women), and 10 µg for infants aged 7 to 11 months. These values assume minimal skin synthesis, built on a target blood level of 50 nmol/L, and EFSA stresses that where there is sun-driven synthesis, the dietary need is lower or may even be zero (EFSA/SACN explanatory note). So 15 µg is a reference built for the darkest-months scenario, not a minimum everyone must hit year-round.

The upper limit is a ceiling, and it is not a goal. EFSA's tolerable upper intake level (UL) is the highest total daily intake from all sources that is not expected to cause harm in the general population. For vitamin D, the current EFSA overview table lists:

• Group: Infants 0 to 6 months; UL (µg per day): 25
• Group: Infants 7 to 11 months; UL (µg per day): 35
• Group: Children 1 to 10 years; UL (µg per day): 50
• Group: Adolescents 11 to 17 and adults, including pregnancy and lactation; UL (µg per day): 100

That is EFSA's UL overview table (read 8 October 2026). It lists the vitamin D opinions of 2012, 2018 for infants, and 2023. EFSA's 2023 opinion, available via Europe PMC, explains the 100 µg figure: the critical endpoint is persistent hypercalciuria (too much calcium in the urine), which may be an earlier sign of excess than high blood calcium. EFSA took a lowest-observed-adverse-effect level of 250 µg per day from two randomised trials and applied an uncertainty factor of 2.5. It also found European populations are unlikely to exceed the UL, except regular users of food supplements with high doses of vitamin D.

The NHS says the same thing in plain words: not more than 100 µg (4,000 IU) a day, because excess supplements can lead to calcium building up in the body (hypercalcaemia). The Gezondheidsraad had described the same 250 µg figure in 2012 as the highest level where no toxic effects were seen; EFSA's later opinion treats it as the lowest level where effects were seen. Same number, different reading, and the reason a margin was built in.

Vitamin D2, D3, and where vegan D3 fits

Supplements come as D2 (ergocalciferol) or D3 (cholecalciferol). The Voedingscentrum says both forms "are active" in the body, but that D3 has a slightly stronger action, and its supplement advice leans towards D3 ("kies liever", which it says the body absorbs better). The Gezondheidsraad's 2012 advice also prefers D3 in supplements and fortified foods, because it considered D3 the more effective form.

The research behind that is two main pieces. A 2012 systematic review and meta-analysis of randomised trials (Tripkovic and colleagues, American Journal of Clinical Nutrition) found D3 raised blood 25(OH)D more than D2 overall. The detail matters: in the abstract, the difference was significant for single large (bolus) doses and "the effect was lost with daily supplementation" (Tripkovic et al., 2012). A later trial by the same group, in 335 healthy South Asian and white European women in Surrey over a winter, gave 15 µg a day as D2 or D3 in juice or a biscuit for 12 weeks. The D3 groups rose about 15 to 17 nmol/L more than the D2 groups (Tripkovic et al., 2017). So D3 does appear to raise blood levels more, including at a daily dose close to public-health amounts. Raising a blood number is not the same as proving a health outcome, and these trials measured the number.

That leaves the question vegans actually have: where does D3 come from? Cholecalciferol is a single molecule, so a label that says D3 means the same compound, whether it was extracted from sheep's wool grease, lichen or algae. What differs is the source and the supplier's process, and we did not find a published head-to-head human trial comparing lichen- or algae-sourced D3 with the usual form. That is a gap in the evidence, not a reason to avoid them. If you're vegan, check that the label says the source and read the amount per serving.

Blood tests: what the numbers mean, according to whom

A vitamin D blood test reports 25-hydroxyvitamin D, written 25(OH)D. It reflects what you took in from food and supplements and what your skin made. Labs in Europe typically report nmol/L; US labs often use ng/mL (divide nmol/L by 2.5 to convert). The trouble is that bodies draw the line in different places, because they are asking different questions:

• Body (year): UK SACN (2016); Level used: 25 nmol/L; What it is for: A "population protective" level almost everyone (97.5%) should stay above, built on musculoskeletal outcomes
• Body (year): Gezondheidsraad (2012); Level used: 30 nmol/L (ages 4 to 70); 50 nmol/L (70 and over); What it is for: Targets used to derive the Dutch intake amounts
• Body (year): EFSA (2016); Level used: 50 nmol/L; What it is for: Target for setting Adequate Intakes; EFSA found increased risk of adverse musculoskeletal outcomes below this level
• Body (year): Endocrine Society (2024); Level used: none set; What it is for: For healthy people, the guideline says levels that provide outcome-specific benefits have not been established in clinical trials

The first three come from the EFSA/SACN note and the Gezondheidsraad advice, and the last from the Endocrine Society's guideline page. Same blood result, different verdict, depending on which line a lab or website uses. A result of 40 nmol/L is fine under one line and low under another.

The 2024 Endocrine Society guideline, in full rather than as a soundbite

The guideline, Vitamin D for the Prevention of Disease (Demay et al., JCEM 2024), is sometimes summarised as "vitamin D doesn't work", which isn't what it says. It addresses people without an established indication for vitamin D treatment or testing, and asks whether giving vitamin D lowers the risk of disease. It updates and replaces the Society's 2011 guideline. Its recommendations, all conditional ("we suggest"), are:

• Group: Children and adolescents 1 to 18; Supplementation: Suggests empiric supplementation, to prevent nutritional rickets and possibly lower the risk of respiratory infections; Routine 25(OH)D testing: No testing recommendation listed
• Group: Adults under 50; Supplementation: Suggests against supplementing beyond recommended intakes; Routine 25(OH)D testing: Suggests against
• Group: Adults 50 to 74; Supplementation: Suggests against routine supplementation beyond recommended intakes; Routine 25(OH)D testing: Suggests against
• Group: Adults 75 and over; Supplementation: Suggests supplementation, because of the potential to lower mortality; daily lower doses preferred over occasional large doses; Routine 25(OH)D testing: Suggests against
• Group: Pregnancy; Supplementation: Suggests supplementation (possible lower risk of preeclampsia and some birth outcomes); Routine 25(OH)D testing: Suggests against
• Group: Adults with high-risk prediabetes; Supplementation: Suggests supplementation alongside lifestyle changes; Routine 25(OH)D testing: n/a

The certainty of evidence behind these is mostly low to moderate. Two things follow. First, "suggests against routine testing" is about screening people with no indication; it explicitly excludes people with a clinical reason such as low blood calcium. Second, the guideline is about preventing disease, not about how to treat an established deficiency, and it is a US-based guideline, written against US intake recommendations. It does not replace the Dutch advice, and the Dutch and Endocrine Society groups don't line up exactly (the Dutch list includes women 50 to 69 and dark-skinned people; the Endocrine Society's list does not). The fact that they differ on some groups is a reason to read each one's scope, not a contradiction to resolve.

If you come across a page promising an "optimal" blood level, ask which guideline it comes from and what outcome that level was tied to. For healthy adults, the 2024 guideline found no outcome-based target.

Too much: hypercalcaemia and when it happens

The Voedingscentrum says you can only get too much vitamin D by taking too many supplements over a long time, which can cause calcium deposits in the body and kidney damage. The Gezondheidsraad lays out the sequence: first too much calcium in the urine (with a higher kidney-stone risk), then a high blood calcium level. Once the kidneys cannot clear the extra calcium, symptoms appear: loss of appetite, weakness, tiredness, disorientation, vomiting and constipation. Over the long term, calcium can be deposited in soft tissue, notably the kidneys.

Most people never get near that. EFSA, as above, sees UL exceedance mainly with regular high-dose supplements. One practical point of ours: vitamin D can turn up in more than one product (a multivitamin, a D3 capsule, a fortified food), so totals can creep. Add up the micrograms across products before comparing the total to the 100 µg ceiling. The Gezondheidsraad also noted that two trials giving very high yearly doses (7,500 µg by injection or 12,500 µg orally) found an increased risk of falls and fractures, and concluded that a very high annual dose is not effective for preventing them and may have unwanted effects.

Interactions and who should ask first

The Farmacotherapeutisch Kompas, the Dutch drug reference, lists some interactions for colecalciferol (Zorginstituut Nederland, Colecalciferol, read 8 October 2026). Thiazide diuretics raise the risk of hypercalcaemia because they reduce the kidneys' calcium excretion. Vitamin D plus calcium together with digoxin can cause heart-rhythm problems. Some medicines (phenytoin, phenobarbital, primidone, rifampicin and glucocorticoids) may reduce the effect of colecalciferol, and others (cholestyramine, orlistat, liquid paraffin) reduce its absorption. It lists existing hypercalcaemia, hypercalciuria and kidney stones as contraindications. If any of that describes you, a pharmacist is the quickest check. We cover the wider topic in our guide to supplement and drug interactions, and how to read a supplement label helps with the micrograms-versus-IU shuffle.

Reading a vitamin D product page: PLNKTN and Upfront as examples

To show how to read a vitamin D product page, here is what the public pages of two brands, PLNKTN and Upfront, said on 8 October 2026. We haven't tested either product.

PLNKTN lists "Vitamine D3 + K2", described on its page as a completely plant-based vitamin D3 supplement from algae. The page states 20 µg of vitamin D3 and 75 µg of vitamin K2 (menaquinone-7) per serving, as one softgel a day, with 30 capsules at €11.95 as a one-off purchase on 8 October 2026 (a subscription is also offered) (PLNKTN product page). The brand's claims are about immune function, normal muscle function and bones and teeth. Upfront lists a "Vitamine D3 + K2" as a 60-count pack at €14 (price shown 8 October 2026); its product page gives no description, form or ingredient amounts, so there is nothing more we can say about it (Upfront).

Whatever you look at, run through the same four checks: which form (D2 or D3), what source if it matters to you, how many micrograms per serving (not just IU or "% of reference"), and what else is in the product. Both of these products pair D3 with K2. The Dutch advice gives amounts for vitamin D on its own, so K2 is a product design choice rather than part of the advice. K2 is a form of vitamin K, and there is one practical caution. The Voedingscentrum's vitamin K page says people who use blood thinners or anticoagulants should be careful with supplements that contain more than 100 µg of vitamin K (read 8 October 2026). PLNKTN's page prints 75 µg of K2 per capsule, under that line; Upfront's page gives no amount. If you take an anticoagulant, ask your pharmacist or doctor before adding any K-containing supplement, whatever the figure. 20 µg is above the 10 µg most groups are advised and equal to the amount advised for people aged 70 and over, and well under EFSA's 100 µg ceiling. Whether that is sensible for you depends on whether you are in one of the groups above, which is a question for you and, if there is a medical reason, your GP.

Where to go next

If you remember one thing: the supplement advice is group-based, the targets differ between bodies, and the 100 µg ceiling is a limit, not a dose. Check the Voedingscentrum page against your own situation, find out which threshold any "deficient" headline used, and keep a blood test for when a doctor has a reason to order it.

For adjacent reading, our magnesium guide covers another nutrient people take for winter-season reasons, and Smart Supplements 101 explains how we approach evidence and labels.

Written by Smart Supplements with AI assistance from the sources linked in the text. It has not been reviewed by a clinician.

Last updated: 12 October 2026

This article is for informational purposes only and is not intended as medical advice. Always consult a healthcare professional before starting any new supplement, especially if you take prescription medication.