After months of nausea and vomiting, a middle-aged man in the UK finally discovered the toxic cause of his health problems: too much vitamin D. His doctors found an overzealous supplement regimen to blame.
The patient lost 28 pounds (12.7 kilograms) in three months and complained to his general practitioner of persistent abdominal pain, dry mouth, diarrhea and vomiting, according to a case study published July 6 in the journal British medical journal. At the hospital, doctors learned that the man’s symptoms had started about a month after he began an intense vitamin regimen suggested by a private nutritionist.
Under the regimen, the patient had been taking 150,000 international units (IU) of vitamin D daily, 250 times the 600 IU recommended by the Mayo Clinic. And he was taking more than 20 other supplements on top of that, including more than the recommended amount of omega-3s, vitamin K2, and folic acid. High levels of serum creatine, a waste product that healthy kidneys remove from the body completely, confirmed that the patient’s kidneys were affected. The man recovered after receiving intravenous fluid for rehydration and being hospitalized for eight days while his kidneys recovered.
Related: Why You Can’t Skip Magnesium If You’re Taking Vitamin D
“A common misconception with dietary supplements, including vitamin D, is that if some are good, then more is better,” Shelby Yaceczko, an advanced practice clinical dietitian at the Center for Human Nutrition at the University of California, Los Angeles. Angeles, who was not involved in reporting the case, told LiveScience in an email. “Unfortunately, that’s not the case and while it’s important to maintain normal vitamin levels, it’s also very important to avoid taking higher doses than are considered safe.”
Megadoses of vitamins can be harmful, according to Yaceczko. Too much vitamin D in the body can cause symptoms such as drowsiness, vomiting, weakness, constipation, bone pain, and abnormal heart rhythms. Routine blood tests are the only way to accurately identify and correct nutritional deficiencies, Yaceczko said. Without this type of follow-up, patients are at risk for toxicities, such as the one seen in the case study. (The case study did not mention whether the nutritionist was performing routine blood tests on the patient, and the report’s authors were not available for comment.)
However, something else may be at play, according to Dr. Heather Tick, a clinical associate professor of family medicine and endowed professor of integrative medicine at the University of Washington in Seattle, who was not involved in the case report. “Everything I was into, it was a bunch of stuff,” she told LiveScience.com. But “generally, you need to take high doses of vitamin D for a much longer time, not just a month” to experience toxicity, Tick added.
According to Yaceczko, the scientific literature suggests that “vitamin D toxicity can occur between 1 [to] 4 months, depending on several factors, as well as how many megadoses the person is taking.”
Tick also said that the case study patient may have had an underlying condition that “predisposes him to accumulate vitamin D.”
Tick added that it’s important to note that conventional medicine doctors may have a bias against supplements and integrative medicine elements, and that could play into the case study’s conclusions.
Yaceczko, who is a registered dietitian, also cautioned that the term “nutritionist” is often used loosely, is an unregulated title, and doesn’t require any education or work experience. Therefore, people should be careful about where they get their nutrition advice and look for medical professionals who have received the necessary training, Yaceczko said.
Originally published on Live Science.
