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Ingredients You Never Want to Find in Your Supplements

Learn the three ingredients in supplements to avoid at all times. 
FACT CHECKED BY Emilia Paluszek

From fish oil to vitamin C, people who are trying to boost their immunity and improve their overall health are turning to supplements. According to the Centers for Disease Control and Prevention, an estimated 58% of U.S. adults ages 20 and over take dietary supplements and while companies promise everything from perfect skin to shiny hair, not all supplements are safe or beneficial. Eat This, Not That! Health spoke with Dr. Jacob Hascalovici MD, PhD as the Clearing Chief Medical Officer who shares what to know about supplements and three ingredients to avoid. As always, please consult with your physician for medical advice. Read on—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.


What to Know Before Taking Supplements

Woman holding a pill in her hand.

Dr. Hascalovic tells us, "While it can be easy to think that supplements are a great idea across the board, it's not always advisable to take more than 100% of the recommended dose of any particular supplement. For one thing, the body cannot always process or use that high of a daily dose, so you may be wasting money. For another, certain supplements can interfere with other vitamins, supplements, or medications, so it's possible they can actually make things worse instead of better. Since they aren't necessarily regulated, monitored, or tested for quality or to ensure that their claims are justified, supplements can be contaminated or low-quality. Finally, your individual experience with specific supplements may be different than others' experiences with them. Some supplements, including ones aimed at weight loss, sexual function or body building, may even lead to an emergency room visit, as happens about 23,000 times a year in the US. We are all unique, and a lot can influence how our bodies function, including how they process supplements."


What to Look For in Supplements

Young Woman Taking Yellow Fish Oil Pill.

Dr. Hascalovic suggests, "The best course of action is to do your homework, buy reputable supplements from highly-regarded sources, remain vigilant for any adverse interactions, and track whether the supplement seems to actually be helping you. Check reviews, research studies, consumer reports, and any other information you can get about particular supplements before you purchase them. Make sure you're getting your information from credible sources – websites that end in .gov or .org are more likely to be accurate. Also read the ingredient list to make sure you're not allergic to any of the contents. When you do that, you can also check for information about whether or not the supplement's maker conducts third-party checks for purity and safety. A seal from ConsumerLab, NSF International, Underwriters Laboratory, or US Pharmacopeia is often a good sign. Keep an eye out for red flags or meaningless phrases such as "pharmaceutical grade" or specific claims about diseases."


Titanium Dioxide


Dr. Hascalovic explains, "A whitening agent, you might find titanium dioxide in sunscreen and cosmetics, as well as in paints and scads of other places. That doesn't mean it's good to eat. The substance has been linked to inflammation in the small intestine, and may not be recommended for people with digestive issues." 


Magnesium Silicate


Dr. Hascalovic says, "The mention of 'magnesium' in magnesium silicate may sound like a desirable additive, but the silicate part can be worrisome. Also called talc, magnesium silicate can be added to some supplements to prevent ingredients from caking or clumping up. The FDA doesn't consider magnesium silicate to be food grade, however, and it may cause issues for the stomach and lungs." 


Heavy Metals


"Listen to heavy metal music as much as you like, but heavy metals like lead and mercury have no place in modern supplements," Dr. Hascalovic states. "Sometimes they sneak in, however, showing up as additives in ashwagandha, turmeric or other supplements to enhance the supplement's appearance. It always pays to check the ingredients and research anything suspicious!"

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