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Dec 18, 2023

These Are the Supplements You Should Avoid Taking Together

DIPA / Getty Images More than half of adults in the United States take some kind

DIPA / Getty Images

More than half of adults in the United States take some kind of supplement or vitamin daily. Depending on the supplement you take, some claim to fill nutrient gaps in your diet and lifestyle while others aim to fight off deficiencies, lower the risk of certain diseases, strengthen specific parts of your body, or support overall health.

While supplements can offer a variety of potential health benefits, experts say it's important to use them wisely and consider the timing of their intake. For example, taking all of your supplements at once after a meal or at a specific time of the day can impact their potency or absorption rates or even cause dangerous health effects.

"Certain supplements can interact with each other, leading to decreased effectiveness, increased risk of side effects, or potential harm to your health," Danielle Crumble Smith, RDN, a certified registered dietitian at Top Nutrition Coaching, told Verywell.

Other experts say people should use supplements with caution, especially since they are not regulated by the Food and Drug Administration (FDA) and most are not vigorously studied.

"Some supplements may have inconsistent ingredients and doses from batch to batch," Marilyn Tan, MD, double board certified in endocrinology and internal medicine and a clinical associate professor of medicine at Stanford University School of Medicine, told Verywell in an email.

Tan said that manufacturers also frequently make health claims that have not been well-studied in randomized controlled trials. In addition, some supplements can cause harm even though they are considered "natural."

If you take any supplements or plan to add some to your lifestyle, here are combinations you should look out for and avoid mixing, according to experts.

According to Crumble Smith, there are certain supplements that shouldn't be taken together because one can negate the effectiveness of the other.

It's important to note that the order in which supplements are taken can affect how well they are absorbed in the body and how effective they are, Mary Sabat, RDN, LD, a registered dietitian nutritionist and an ACE-certified trainer, told Verywell in an email. For example, some supplements like calcium are best taken with food to enhance absorption, while others like iron are better absorbed when taken on an empty stomach.

Experts say it's also important to pay attention to powders and other products that contain various supplements, including protein powders, gummies, energy drinks, or bars. That's because some of the ingredients in these products may not work well together or could pose health risks when combined with other things, Crumble Smith said.

For example, some people may blend athletic powders or caffeine with herbs, stimulants, and supplements like ashwagandha and Rhodiola. In the short-term, mixing these things can provide an energy boost. But there may be health risks associated with long-term use.

"Rhodiola is really common and you’ll see that in products in combination with caffeine," Crumble Smith said. said. "In the long-term, if this is something that people are taking on a consistent basis, it could stress the adrenal gland. People might experience adverse symptoms like anxiety, insomnia, or even heart palpitations."

Whatever powder or supplement blend you decide to use, be sure to look at all of the active and inactive ingredients and check for any FDA warnings, Tan said. You may also want to inform your healthcare provider about all of the supplements you are taking, including pills, liquids, powders, and topical creams.

Before you decide to take any supplements, experts suggest consulting with your healthcare provider to determine the best options for your individual needs. This is especially important for people with pre-existing medical conditions or those who are taking medications.

"Supplements are great, but they’re not meant to replace balanced eating, sleep, or exercise," Crumble Smith said. "If you want to take supplements, first address those basics like sleep, hydration, eating well, and exercise. Then you can meet with a healthcare provider or dietitian and figure out where there might be gaps where supplementation could help."

If you are taking supplements or plan to add any to your lifestyle, experts recommend talking with your healthcare provider first. A professional can help determine which supplements you should avoid mixing and which ones you shouldn't take if you’re on certain medications.

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By Alyssa HuiAlyssa Hui is a St. Louis-based health and science news writer. She was the 2020 recipient of the Midwest Broadcast Journalists Association Jack Shelley Award.