Taking too much could cause serious health problems including hypercalcemia – here’s what you need to know
Sophie Buchan Money and Lifestyle Writer
00:13, 14 Feb 2026
The NHS guidance is displayed on the website(Image: Getty)
Vitamin D is celebrated as the ‘sunshine vitamin’ that we’re encouraged to supplement, particularly throughout the winter months. However, health experts have said that taking too much could be doing more harm than not taking them at all and you may need to stop.
Vitamin D toxicity, medically termed hypervitaminosis D, occurs when your body becomes overloaded. According to specialists from the Mayo Clinic while “rare”, it can “have a serious effect on health”.
This condition typically impacts people who take too many supplements. There’s no cause for concern regarding your diet, though, as consuming oily fish won’t place you at risk.
People who take a Vitamin D supplement in the winter have been urged to exercise caution(Image: Oleg Breslavtsev via Getty Images)
“Even items with added vitamin D, such as cow’s milk, don’t have large amounts of the vitamin in them,” it assures.
Despite this, specialists say that the primary worry with too much vitamin D is raised calcium levels in the bloodstream, known as hypercalcemia. This can trigger stomach upset, vomiting, weakness, and frequent urination. It may also result in bone pain and kidney complications like kidney stones.
Managing vitamin D toxicity involves stopping the supplements. You may also require IV fluids for hydration, whilst your GP could prescribe medicines such as corticosteroids or bisphosphonates to bring your blood calcium back to safe levels.
How to prevent vitamin D toxicity
Experts at the NHS advise: “Do not take more than 100 micrograms (4,000 IU) of vitamin D a day as it could be harmful. This applies to adults, including pregnant and breastfeeding women and the elderly, and children aged 11 to 17 years.
“Children aged 1 to 10 years should not have more than 50 micrograms (2,000 IU) a day. Infants under 12 months should not have more than 25 micrograms (1,000 IU) a day.”
In more advice, the NHS and Mayo Clinic both warn that some healthcare professionals may prescribe higher doses. Experts at the Clinic note: “This may be done to help treat health conditions such as low levels of vitamin D.
“Talk with your healthcare professional before taking vitamin and mineral supplements. That way, you can find out if a supplement is safe for you.”
Vitamin D-rich foods
Taking vitamin D is vital at this time of year – but it it possible to take too much, doctors say(Image: Getty Images)
For those wanting to boost vitamin D intake naturally without supplements, the British Heart Foundation (BHF) has identified several foods you can incorporate into your meals.
Oily fishMushroomsEggsLiverRed meat
It adds that you can try and include vitamin D-enriched fruits too. “There is no vitamin D in fruits,” it warns.
“However, some fruit products can be fortified with vitamin D, including certain juices, smoothies and fruit yoghurts.” Some oily fish you can try include sardines, canned in brine, grilled mackerel, steamed salmon, and grilled herring.
