High doses of vitamin A -- and other fat-soluble vitamins like E and K -- can build up in the body and become toxic. Other risky supplements include the minerals iron and selenium.

Women who might become pregnant should be especially cautious with vitamin A supplements or avoid them entirely .

Vitamin D dosage recommendations can vary depending on several factors, including your age, skin color, medical history, and where you live. Vitamin D is commonly known as the “sunshine vitamin ...

Some people should avoid vitamin A supplements due to the potential health risks. These include, but are not limited to: Excessive vitamin A during pregnancy can cause congenital birth defects, says ...

The ideal dose of vitamin B12 varies based on your sex, age, and reasons for taking it. This article examines the scientific evidence behind recommended dosages for B12 for different people and uses.

Medically reviewed by Jonathan Purtell, RDN The best time to take vitamin C to boost your immune system is with meals ...

BARCELONA, Spain — The addition of high-dose vitamin D supplementation to standard chemotherapy plus bevacizumab did not result in a significant progression-free survival benefit in patients ...

Vitamin D supplements may have other benefits, but in otherwise healthy folks with sufficient levels of the nutrient, "our findings do not suggest benefits of long-term moderate- or high-dose ...

Using significantly higher doses of vitamin D than recommended for five years did not affect the incidence of type 2 diabetes in elderly men and women, according to a new study from the University ...

Source Reference: Thouvenot E, et al "High-dose vitamin D in clinically isolated syndrome typical of multiple sclerosis: the D-Lay MS randomized clinical trial" JAMA 2025; DOI: 10.1001/jama.2025.1604.

High-Dose Vitamin D May Shift Calories From Fat to Muscle, Reveals Study – Here's What to Know. A new insight into how your body utilises and stores calories has emerged, ...

High doses of vitamin C could be a new breakthrough in treating cancer. The University of Iowa Health Care Carver College of Medicine has shared results from a randomized, phase 2 trial testing ...