Many vitamins and minerals include 1,000 percent or more of the recommended daily allowance. Is it dangerous to take this much every day? Is it possible to take too many supplements?

It’s not too surprising to learn that, yes, we can take too many supplements and that doing so can be dangerous. The following supplements can be harmful if taken in excessive amounts:

Iron

Unless advised to do so by your doctor, never take iron supplements. Your doctor will only recommend taking iron after he has performed tests which reveal iron deficiency anemia, and has discovered the source of blood loss. Our bodies cannot eliminate iron except through blood loss, and blood accumulation increases the risk of cancer and heart disease. Avoid products that contain iron unless you are a premenopausal woman with heavy menstrual flow.

Vitamin A

Excessive intake of some forms of this, specifically retinol or retinoic acid, can be toxic and lead to hair loss, confusion, liver damage and bone loss. Excessive use can also lead to hypervitaminosis A, an illness that causes many symptoms, including drowsiness, irritability, headache, bone pain, blurred vision, vomiting, and peeling skin. Severe cases can end in death. Instead of retinol or retinoic acid, use plant-derived vitamin A precursors such as beta-carotene.

Vitamin E

High doses of Vitamin E may interfere with the body’s ability to clot blood. This poses a risk to people taking prescribed blood thinners or aspirin. In those cases, Vitamin E supplements should only be taken under a physician’s supervision.

B Vitamins

Although these do not accumulate in the body, taking too much of some of the B Vitamins can damage nerves. Taking 2,000 to 3,000 mg per day of niacin can cause nausea, jaundice, and elevated liver enzymes. Especially if you’re pregnant, have ulcers, gout, diabetes, gallbladder disease, liver disease, or have had a recent heart attack, you should avoid high doses and time-release formulas of niacin. Anyone taking niacin should only do so under a physician’s supervision, and should have liver function tests done before starting and periodically thereafter.

Read the full article here: Can You Overdose on Vitamin and Mineral Supplements?