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6 Worst Supplements You Should Stop Taking Right Now, Say Dietitians

They may be doing more harm than good.
FACT CHECKED BY Olivia Tarantino

All supplements are not created equal. In fact, some supplements may be doing more harm than good.

"Supplements are meant to replenish deficiencies. They were never meant to replace a healthy diet and should be taken only when an individual can't meet needs due to either dietary restrictions or a malabsorption disease," says registered dietitian Paula Doebrich, RDN, MPH, owner of private nutrition practice, adding that it is important to keep in mind that supplements are not regulated by the FDA, therefore manufacture have a lot of freedom in what products they sell and promote.

"Always make sure you talk to a healthcare professional before taking supplements. Some substances used in supplements may interact with medications, including antidepressants or blood thinners," she continued, noting that you should also keep in mind that often the claim on a supplements bottle is not rooted in science and simply is marketing. "While most consumers believe supplements count as drugs and are regulated the same way, this is not the case. They are the least regulated product on supermarket or pharmacy shelves."

Read on for six supplements some people shouldn't take and why, and for more on how to eat healthy, don't miss The #1 Best Juice to Drink Every Day, Says Science.

Energy-boosting supplements

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Do you regularly take such supplements pre-workout or to give you an a.m. boost? It's time to reevaluate. "Any 'energy boosting' supplement is likely to contain caffeine. Energy supplements often have high levels of caffeine and most consumers will take them on top of their daily coffee. Excessive intake could lead to complications, such as anxiety, insomnia, fast heart rate, diarrhea, or high blood pressure," said Doebrich. "Energy supplements are common causes for emergency room visits due to extreme side effects." Here's more on why you should avoid caffeine pills.

Herbal supplements

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These buzzy supplements may not be worth the hype. "Herbal supplements are usually derived from plants or herbs, but they're not necessarily safe or effective," says Ronald Smith, RD, from EatDrinkBinge.com. "It's possible that they could contain ingredients that interact with prescription drugs or cause dangerous side effects," he added. As always, consult with your doctor before adding any supplement, even herbal ones, to your routine.

St. John's Wort

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As Doebrich notes, St. John's Wort is a popular herb used to naturally relieve depression, insomnia, or menopause symptoms. "But while this powerful herb could help with certain conditions, it may also cause life-threatening complications when taken together with an antidepressant," she said. "Additionally, it could potentially reduce the effectiveness of certain birth control pills, chemotherapy or antivirals."

 6 Popular Supplements That Don't Actually Work, According to Experts

Ashwagandha

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This supplement may be trendy, but experts warn that some people should steer clear. "The herb is said to improve immunity, have a calming effect, and reduce blood pressure; however, ashwagandha might increase thyroid hormone production. This might increase the side effects of thyroid medications," says Doebrich. "The herb could also lower blood sugar levels. People with diabetes should avoid taking ashwagandha as blood sugar might drop to dangerously low levels." That's why Doebrich recommends that anyone taking ashwagandha should monitor for low blood sugar symptoms such as tiredness, anxiety, or a fast heartbeat.

Fish oil supplements (in certain cases)

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"Fish oil supplements contain omega-3 fatty acids, which can help lower blood pressure, triglycerides, and cholesterol levels as well as reduce inflammation throughout your body," explained Smith. "But some people have an allergic reaction to fish oil (which can cause hives), while others may experience diarrhea, nausea, and stomach pain after taking the supplement. If you have heartburn, ulcers, or GERD (gastroesophageal reflux disease), fish oil isn't recommended for you because it can irritate your esophagus." Researchers also recently found fish oil pills may not be all they are cracked up to be.

Too much calcium from supplements

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Could you be in this camp? "Excessive calcium from supplements could increase risk for atherosclerosis and kidney stones," says Doebrich. "When taking calcium supplements, it is best to stick to the recommended dose: 1,000 milligrams for adults between 18-50 and 1,200 milligrams for older adults."

Perri O. Blumberg
Perri O. Blumberg is a freelance food, health, and lifestyle writer. Read more about Perri O.