After visiting a private nutritionist, the man began taking more than 20 over-the-counter supplements every day, including 50,000 International Units (IU) of vitamin D three times a day. That’s a dose hundreds of times higher than standard dietary recommendations.
Within a month, the man started experiencing nausea, abdominal pain, diarrhea and repeated bouts of vomiting, along with leg cramps and ringing in the ears.
The man, whose name was not disclosed, learned about the supplements from a radio talk show and then contacted the nutritionist on the show, said Dr. Alamin Alkundi, a co-author of the report and an endocrinologist at William Harvey Hospital in East Kent, UK, who treated the man.
“Regulatory registration is not required for nutritionists in the UK and their title is not protected, so anyone can practice as a nutritionist,” says Alkundi. said in an email.
Unlike water-soluble vitamins, which the body can easily eliminate, vitamin D and its cousins A, E, and K are stored in the body’s liver and fat cells until needed. Consuming well above the recommended daily dose can lead to toxic levels.
The man stopped taking the supplements when his symptoms started, but his condition did not improve. By the time he was referred to the hospital two months later, he had lost 12.7 kg and his kidneys were in trouble. Tests showed that he had taken an overdose of vitamin D, a condition called hypervitaminosis D.
Daily Recommended Levels
The body needs vitamin D. The main job of the vitamin is to help the body absorb calcium from the gut – in fact, the body cannot absorb calcium unless vitamin D is present. The vitamin also plays a role in immune system health, brain cell activity, and how muscles function.
Too much vitamin D in the blood leads to hypercalcemia, which occurs when the level of calcium in your blood is above normal. The man in the BMJ case study was diagnosed with hypercalcemia, which can weaken your bones, cause kidney stones and interfere with the functioning of your heart and brain.
The man was hospitalized for eight days and treated with drugs to lower the calcium level in his blood. A follow-up two months later found that his blood calcium levels had dropped to near normal. Although the man’s vitamin D level had also improved significantly, it was still high, Alkundi said.
“A plan was put in place to periodically monitor both parameters in the clinic to monitor the levels falling to normal levels. We have been in contact with him and he reported (he is feeling) much better, but still not his normal self,” Alkundi said.
“He really wants his story to be known to warn others,” Alkundi added.
Signs of vitamin D overdose can include drowsiness, confusion, lethargy, and depression, and in more severe cases, it can lead to sedation and coma. The heart can be affected: blood pressure can rise and the heart can beat irregularly. In severe cases, the kidneys can develop renal failure. Hearing and sight can be affected.
Where to get vitamin D
The body makes enough vitamin D when the skin is exposed to sunlight. In fact, going outside for 10 to 15 minutes in a bathing suit in the summer will “generate 10,000 to 20,000 IU of vitamin D3 in adults with light skin pigmentation,” according to the AAP.
However, going out in direct sunlight in the afternoon is not recommended because of the risk of skin cancer, so dermatologists and the AAP say it’s best to use sunblock if you’ll be exposed for extended periods of time. Sunscreens can decrease the body’s ability to process vitamin D.
When considering vitamin D supplements, daily dietary vitamin D levels should be included in the decision, experts warn. In addition to fortified foods, eggs, cheese, shiitake mushrooms, salmon, swordfish, tuna, rainbow trout and beef liver contain vitamin D, as well as cod liver oil.
Anyone concerned about their vitamin D levels should have them evaluated by a doctor, experts say.
“Patients are encouraged to ask their GP’s opinion on any alternative therapies or over-the-counter medications they are taking or want to start,” Alkundi said.