Vitamin D Toxicity

Vitamin D toxicity, also called hypervitaminosis D, happens when vitamin D builds up in the body to harmful levels. Because vitamin D helps the body absorb calcium, too much of it can drive blood calcium too high (hypercalcemia). Symptoms can include nausea, vomiting, loss of appetite, constipation, excessive thirst and urination, confusion, muscle weakness, and kidney problems such as kidney stones. Severe cases can cause kidney failure and dangerous heart rhythms.

Sun exposure and normal food do not cause toxicity. It comes from very high doses of supplements taken over time, or from products that contain far more vitamin D than the label says. The National Institute on Aging advises that adults over 50 get 600 to 800 IU of vitamin D per day depending on age, but not more than 4,000 IU each day.

That link to supplements is why vitamin D toxicity appears in litigation. Dietary supplements do not need FDA approval before sale, and manufacturing errors or mislabeling can produce products with many times the stated dose. People harmed by an overdosed product may bring product liability claims, and buyers of mislabeled products may join consumer class actions seeking refunds. Keep the bottle, lot number, and receipt, and ask your doctor to document your blood calcium and vitamin D levels.

Anyone taking high-dose vitamin D should talk with a doctor about testing, and nothing here is medical advice. See our page on supplement mislabeling lawsuits and our guide on recalls versus class actions.