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Dangers of Taking Supplements

Buyer beware.

If you're taking over-the-counter supplements, be careful—not all of them are safe, and certain dosages can be harmful to your health. "It's recommended to always talk with your doctor before taking any sort of supplement," explains internal medicine specialist Ronan Factora, MD. "Unregulated supplements can pose a serious risk if taken with other medicine, in excessive amounts or taken for an unconfirmed medical problem. Speaking with your doctor can help determine potential interactions. Often, asking the pharmacist about any specific concerns you have about a new supplement is worthwhile, too. It's always better to be safe than sorry." Here are five dangers linked to taking supplements, according to experts. Read on—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.


Prescription Medications

closeup woman taking high blood pressure medication

Certain supplements can interfere with prescription medications. "Garlic, ginger or ginkgo extracts could potentially interact with blood thinners and increase the risk of bleeding," says Dr. Factora. "And St. John's Wort is commonly taken for depression, but it can interact with other antidepressants being taken at the same time."


Protein Powder

drinking protein shake

Do you know what's in that harmless-looking protein powder? Researchers at the Clean Label Project investigated 134 different types of protein powder and discovered many contained dangerous levels of toxins, heavy metals, and BPAs. "I don't recommend using protein powders except in a few instances, and only with supervision," says registered dietitian Kathy McManus, director of the Department of Nutrition at Harvard-affiliated Brigham and Women's Hospital. 


Colon Cleanse Supplements

Colon Cleansers

"Colon cleanses and enemas are safe only when prescribed by a licensed physician before a colonoscopy or for treatment of constipation," says David R. Heiman, MD. "They can come with their own set of side effects, including bloating, dehydration, and cramping, but these are temporary and last for just a day before a colonoscopy. Non-prescription colon cleanses may make big promises, but the truth is that they're more likely to cause harm than good… Laxatives and enema solutions can lead to severe abdominal pain, cramping, and bloating. These can last hours or even days afterward."


Energy Supplements


Over-the-counter energy supplements can contain dangerous levels of caffeine, doctors warn. "Small amounts of caffeine are not generally dangerous to most people," says Anne-Michelle Ruha, MD, a medical toxicologist at Banner Health. "But large amounts can increase blood pressure and accelerate the heart rate. There are many situations in which these side effects can be hazardous."


Weight Loss Supplements

weight loss supplements

Weight loss supplements land thousands of people in the ER every year, and the FDA's list of tainted weight loss supplements is extensive. "Patients quickly get into trouble when they take powerful prescription weight loss medication outside a doctor's supervision, combine multiple weight loss supplements – particularly stimulants aimed to speed up metabolism – with illegal stimulants like methamphetamine or cocaine," says Michael Daignault, MD. "They present to the ER with an accelerated heart rate and elevated blood pressure, altered or agitated mental status, potential damage to liver or kidneys, and diarrhea or rectal bleeding."


Ferozan Mast
Ferozan Mast is a science, health and wellness writer with a passion for making science and research-backed information accessible to a general audience. Read more about Ferozan
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