Doctors are warning people about taking Vitamin D after a man began to experience scary side effects.
For many people, vitamin D supplements become part of the routine during winter, when shorter days and persistent cloud cover can limit sunlight exposure.
Medical guidance often stresses the importance of getting enough vitamin D at this time of year because it helps support bone health.
But clinicians are also urging caution after a case in which excessive use of the supplement was linked to serious health problems.
According to an account published in the journal BMJ Case Reports, a man who was admitted to hospital after taking very high amounts of vitamin D was found to have developed ‘hypervitaminosis D’.
His family encouraged him to seek medical help after he began reporting severe symptoms, alongside a 28 lb weight loss over three months.
The journal reports that he experienced vomiting, nausea, abdominal pain, leg cramps, tinnitus, dry mouth, increased thirst, diarrhea, and continued weight loss.
The issues reportedly started after about a month of following a rigorous supplement regimen recommended by a nutritional therapist.
The middle-aged man, who had a complex medical history including tuberculosis, an inner ear tumor, deafness in the affected ear, a build-up of fluid in the brain, bacterial meningitis, and chronic sinusitis, was found to be taking more than 20 supplements each day — including an amount of vitamin D said to be seven times higher than his required level.
BMJ Case Reports states he was taking vitamin D 150000 IU, while typical daily guidance is 10 mcg or 400 IU.
He was also taking vitamin K2 100 mg daily, vitamin C, more than double his vitamin B9 (folate)requirement at 1000 mg, vitamin B2 (riboflavin), vitamin B6, omega-3 2000 mg twice a day — described as almost 10 times the suggested daily limit — as well as additional vitamins, minerals, probiotics, and other health supplements.
Tests showed not only elevated vitamin D levels, but also excess calcium and slightly raised magnesium.
Doctors ultimately diagnosed him with acute kidney injury. He remained in hospital for eight days, where he received intravenous fluids and bisphosphonates to reduce calcium levels in his blood.
Although his readings improved over the following two months, his vitamin D levels were still considered far too high.
“Given its slow turnover (half-life of approximately 2 months), during which vitamin D toxicity develops, symptoms can last for several weeks,” the authors said.
“This case report further highlights the potential toxicity of supplements that are largely considered safe until taken in unsafe amounts or in unsafe combinations,” they added.