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I'm a Doctor and Beg You to Stop Taking These Supplements

Learn five supplements that doctors and healthcare experts advise taking.
FACT CHECKED BY Emilia Paluszek

While TV ads make it clear that not all medications are safe with their long list of potential dangerous side effects at the end of the commercial, that's not the case with supplements. Dietary supplements can provide beneficial results, especially when it comes to vitamin deficiencies, but that doesn't mean they're all without risk and effective. Many can cause harmful side effects and should not be taken, according to experts Eat This, Not That! Health spoke with. Read on—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.


Vitamin B-17

Young Woman Taking Yellow Fish Oil Pill.

Kelly Johnson-Arbor, MD, FACEP, FUHM, FACMT Medical Toxicologist and Co-Medical Director at the National Capital Poison Center tells us, "This 'vitamin' actually contains amygdalin, which is broken down into cyanide within the human body. Although vitamin B-17 is sometimes touted as an alternative treatment for cancer, it is more commonly recognized as a potent poison due to its production of cyanide. People have experienced severe cyanide toxicity and death after taking "vitamin B-17" for treatment of cancer."


Turmeric Without the Addition of Piperine

turmeric in bowl and wooden spoon
Shutterstock / monticello

Dr. Johnson-Arbor explains, "Turmeric is used as a natural remedy against inflammation, cancer, and infection. The main active ingredient in turmeric, curcumin, is poorly absorbed by the human gastrointestinal system, so piperine (a component of black pepper) is often added to turmeric formulations to enhance intestinal absorption of the drug. In one study curcumin was undetectable of the blood of human subjects when it was given by mouth alone, but the addition of piperine increased the bioavailability 2000%. Basically, if people take turmeric without piperine, it's not absorbed by the human body. Fortunately, many turmeric preparations also contain piperine as an ingredient."



assortment of red pills and capsules of iron supplements

According to Dr. Jacob Hascalovici MD, PhD Clearing Chief Medical Officer, "

While iron supplements can benefit people with anemia, the usefulness of copper and iron supplementation drops off rapidly for women after the age of 50. In fact, these supplements may actually raise the risk of Alzheimer's and heart disease, so it's advised to avoid them after 50 or so. Copper and iron can be found in some meats, leafy greens, beans, and nuts."


Vitamin B3

young woman taking pill
Shutterstock / New Africa

Jordyn Mastrodomenico (LCADC, LAC, CTP) Clinical Director, ChoicePoint shares, "Vitamin B3 is known as niacin. It is used to control cholesterol levels in patients with a history of cardiovascular disease. However, it increases the chances of developing low blood pressure which is harmful. It causes blurring of vision by increasing fluid in the eyes. In addition, niacin causes tiredness, nausea, and diarrhea."




Mastrodomenico says, "Folate is not advised for post-menopausal women as it reduces plasma levels and enhances hot flashes. Generally, folate causes intestinal disturbances such as nausea, gas, stomach pain, and bloating. In some people, it causes a complete loss of appetite leading to electrolyte imbalance and malnutrition. Folate increases the chances of developing sleep and memory disorders."


Poison Control Can Help With Side Effects from Supplements

taking vitamin

Dr. Johnson-Arbor urges, "People who have unwanted or unexpected symptoms after vitamin or supplement use should contact poison control for expert advice. There are two ways to contact poison control in the United States: online a or by phone at 1-800-222-1222. Both options are free, confidential, and available 24 hours a day."

Heather Newgen
Heather Newgen has two decades of experience reporting and writing about health, fitness, entertainment and travel. Heather currently freelances for several publications. Read more about Heather