Safety and side effects

Taken in appropriate doses, vitamin D is generally considered safe.

However, taking too much vitamin D in the form of supplements can be harmful. Children age 9 years and older, adults, and pregnant and breastfeeding women who take more than 4,000 IU a day of vitamin D might experience:

• Nausea and vomiting
• Poor appetite and weight loss
• Constipation
• Weakness
• Confusion and disorientation
• Heart rhythm problems
• Kidney stones and kidney damage