A doctor has now warned against consuming a “high dose” of this supplement
Fiona Callingham Lifestyle writer
13:13, 06 Nov 2025
A doctor has issued a warning about taking a common supplement this winter(Image: Getty)
A health expert has issued a warning about a popular winter supplement that could potentially damage your wellbeing. The doctor cautioned that taking too much of this common vitamin could actually make your bones more fragile.
Countless Brits rely on dietary supplements to achieve their daily vitamin and mineral intake. While a nutritious, balanced diet should supply all the nutrients your body requires, supplements can sometimes be needed to bridge nutritional shortfalls.
This is especially true for vitamin D, which our bodies manufacture when we’re in sunlight. As a result, the NHS recommends taking it as a supplement throughout autumn and winter when sunshine hours are reduced.
This vital vitamin regulates calcium and phosphate concentrations in the body, both essential for keeping bones, teeth and muscles healthy. A shortage can lead to bone malformations such as rickets in youngsters, and skeletal discomfort from osteomalacia in grown-ups.
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However, like all supplements, there are crucial cautions to bear in mind. In a video posted on TikTok, Doctor Suraj Kukadia warned against consuming “high dose” vitamin D.
Dr Kukadia, widely recognised as Dr Sooj, said: “Taking a really high dose of vitamin D for a prolonged period of time can make your bones more brittle.”
The NHS supports his caution with official recommendations. On its website, the health authority explains: “Taking too many vitamin D supplements over a long period of time can cause too much calcium to build up in the body (hypercalcaemia). This can weaken the bones and damage the kidneys and the heart.”
The recommended daily dose of vitamin D is 10 micrograms (mcg) – or 40 IU. Consuming more than 100mcg daily could prove “harmful”.
The NHS continues: “If you choose to take vitamin D supplements, 10 micrograms a day will be enough for most people. 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 between one and 10 years shouldn’t go beyond 50 micrograms (2,000 IU) daily.
Infants under 12 months shouldn’t receive more than 25 micrograms (1,000 IU) per day. Beyond this, certain people have medical conditions which mean they might not safely manage such quantities.
“If in doubt, you should consult your doctor,” the NHS advises. “If your doctor has recommended you take a different amount of vitamin D, you should follow their advice.”
It’s not possible to overdose on vitamin D through sun exposure. Nevertheless, you should always protect or cover your skin during extended periods outside to reduce the risk of skin damage and skin cancer.
Numerous foods also provide as brilliant sources of vitamin D. These include:
Oily fish – such as salmon, sardines, trout, herring or mackerelRed meatEgg yolksFortified foods – including certain fat spreads and breakfast cerealsLiver (avoid liver if you’re pregnant – find out about foods to avoid in pregnancy)
For more information, visit the NHS website here.