Four vitamin D overdose warning signs you should know about

During winter, your body may not get enough vitamin D from sunlight, so NHS recommends taking supplements - but in moderation.

Four vitamin D overdose warning signs you should know about
During winter, your body may not get enough vitamin D from sunlight, so NHS recommends taking supplements - but in moderation.
14:22, 22 Jan 2026
Updated 14:23, 22 Jan 2026
Female hands holding pills and glass of water, taking medicine in morning
Female hands holding pills and glass of water, taking medicine in morning(Image: Getty Images)
Everything you need to know about symptoms of Vitamin D overdose
The NHS recommends that all adults in the UK take a daily 10 microgram vitamin D supplement during the darker months from October to March to support bone, muscle, and immune health. Sunlight alone is insufficient for vitamin D production in this period.
UVB rays from the sun trigger vitamin D production in the skin, but autumn and winter sunlight is too weak, making supplementation necessary. Dietary sources alone are unlikely to provide enough vitamin D.
Biomedical scientist Tobias Mapulanga warns that excessive vitamin D intake can cause certain serious side effects. Symptoms often appear soon after increasing dosage or using sprays and gummies in addition to tablets.
Research shows 42 percent of UK adults took vitamin D supplements in the past year, but some products contain doses up to 12.5 times the safe upper limit. NHS England reported 42 cases over two years where high-strength vitamin D caused health issues, sometimes requiring hospital treatment.
Warning signs of overconsumption include excessive thirst and urination, which indicate disrupted fluid and salt balance. To recover, reduce intake to a single 10 microgram tablet and avoid extra supplements.
Gastrointestinal issues such as nausea, burping, or stomach upset signal too much vitamin D. Experts advise switching to a basic cholecalciferol tablet, taking it with food, and avoiding sprays, gummies, or fortified drinks.
Increased bone or muscle pain is another red flag of excess vitamin D. Reducing dosage, staying hydrated, and consuming mineral-rich foods can help alleviate cramps and stiffness.
Cognitive symptoms like brain fog or headaches may result from high vitamin D or additives in multivitamins. Stick to a single 10 microgram D3 tablet, monitor all sources of vitamin D, and track symptoms carefully to prevent unintentional overdose.