According to the Daily Express, a doctor has cautioned that a common supplement could damage wellbeing, with vitamin D posing specific dangers. Multiple reports indicate that taking too much vitamin D supplements can cause hypercalcemia, or high calcium levels in the blood. The NHS advises that consuming more than 100 micrograms (4,000 IU) of vitamin D daily could be harmful.
Other supplements also carry risks if taken in excess. 5mg a day for men and 7mg for women can weaken immunity long-term by interfering with copper absorption. 5mg (1,500mcg) can damage the liver, and pregnant women should avoid high doses completely.
For vitamin C, the UK recommended intake is 40mg per day, and absorption becomes less efficient at higher doses. Supplement interactions with medications present additional dangers. Calcium, magnesium, iron, and high-dose vitamin C can reduce the absorption of antibiotics, thyroid medication, and some blood pressure drugs.
One of the most common mistakes is stacking products that contain the same ingredients, leading to tripled intake. Despite these risks, some supplements can be beneficial when taken appropriately. The NHS recommends a daily dose of 10 micrograms (40 IU) of vitamin D for most people.
In winter, vitamin D is sensible for most adults, omega-3 with EPA and DHA supports brain and heart health, and magnesium can help with sleep and muscle tension.