Health experts warned that some supplements can interact with certain medications and reduce their effectiveness, according to Eating Well website.
While these supplements are usually sold over-the-counter, taking them without asking a health care provider can have dangerous impact on your health.
Naturopathic doctor Jacob Wolf said that for instance, some vitamin and mineral supplements can interfere with absorption of medications.
Other supplements can bind with medications, preventing the drug from being utilized in the body, or they may be metabolized by the same or similar pathways as medications, explains Wolf. That can have a dangerous impact on your health.
Top offenders include calcium, magnesium, iron, fiber, activated charcoal and vitamins C and K.
Minerals like calcium, magnesium and iron can bind with medications, especially levothyroxine, a drug used to treat hypothyroidism, said Wolf.
“This can impact how levothyroxine is utilized in the body, adversely affecting treatment,” he explained.
These minerals can also interact with antibiotics in the tetracycline and fluoroquinolone class, said pharmacist Amanda Corbett.
Taking these mineral supplements at the same time as antibiotics may reduce the bioavailability of the antibiotic, creating risks like bacterial resistance or ineffective treatment.
And while scientists affirm fiber is an important nutrient for digestive regularity, healthy cholesterol levels and blood sugar management, supplementing isn’t always a great idea, as large doses can impact the absorption of certain medications.
Fiber-rich foods are a cornerstone of blood sugar management, even for those taking blood sugar–lowering medications, like metformin.
Fiber may also impair the effectiveness of other drugs, including digoxin (which treats certain heart conditions) and levothyroxine for hypothyroidism, Wolf said.
Therefore, if you do choose to take a fiber supplement, Wolf recommended speaking with your health care provider about spacing out your fiber and medication doses.
As for activated charcoal, it is a form of carbon that is used in the emergency room to treat the ingestion of toxic drugs and poisons.
“Activated charcoal acts like a sponge and can bind to many medications. It is best to completely avoid activated charcoal if on any life-critical medication,” said Wolf.
For Vitamin C, it is an important antioxidant that protects cells from free radical damage and supports proper immune system function.
However, if you are undergoing chemotherapy treatment for cancer, experts strongly caution against taking vitamin C supplements.
“Vitamin C can lead to certain chemotherapies being less effective or ineffective in treating cancer,” said Corbett.
Vitamin E, another antioxidant, can also interfere with chemotherapy’s effectiveness.
If taking Vitamin K, which is a fat-soluble vitamin that helps blood clot and shores up bone health, you should know that it can reduce the effectiveness of a blood-thinning medication called warfarin (Coumadin).
That, in turn, can make blood more likely to clot, which can lead to a heart attack or stroke.
If you are taking warfarin, you don’t necessarily need to avoid vitamin K, but it is critical to keep the amount you consume—from both foods and supplements—consistent to avoid clotting problems.
Experts advise that to take supplements safely, consult with your health care provider.
Many supplements can interact with medications, and so it’s critical to connect with your prescribing health care provider to make sure that the supplements you’re taking play nice with your medications.
Also, look for those that have been independently tested in a laboratory, recommended Corbett.
Experts say you should also know how much to take. Supplement dosages are listed on the label, but they aren’t standardized.
That means they can vary from product to product, and may far exceed safe levels.