Are those “all natural” supplements helping or harming you? Even seemingly innocent over-the-counter supplements can cause harm to your health. “Supplements may interact with other medications you’re taking or pose risks if you have certain medical conditions, such as liver disease, or are going to have surgery,” says Jeffrey Millstein, MD, via Penn Medicine. “Some supplements also haven’t been tested in pregnant women, nursing mothers or children, and you may need to take extra precautions.” Here are 7 popular supplements that could be hazardous to your health.
RELATED: “Ozempic Supplements” Are on the Rise for Weight Loss.
Caffeine Pills
ShutterstockCaffeine pills can be dangerous, experts warn. “While consumers of commonly available caffeinated products such as coffee, tea, and soda may be aware of caffeine’s less serious effects – such as nervousness and tremors – they may not be aware that these pure and highly concentrated caffeine products are much more potent and can cause serious health effects, including rapid or dangerously erratic heartbeat, seizures and death,” warns the FDA. “Vomiting, diarrhea, stupor and disorientation are also symptoms of caffeine toxicity. Pre-existing conditions can intensify the effects of caffeine and make these products even more dangerous for some individuals.”
Iron Supplements
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If you’re past the menopause, you might be taking too much iron. “Iron plays a key role in younger women’s diets for menstrual cycles and pregnancy, but the recommendations for iron after menopause significantly decrease,” says Beth Czerwony, RD, LD, via the Cleveland Clinic. “Despite the lower guidelines (8 mg per day after age 50) many postmenopausal women still take supplements that contain iron and copper. One study linked excess iron and copper to increased incidence of Alzheimer’s disease and heart disease.”
Vitamin C
iStockIt’s possible to take too much vitamin C, and the result may be very unpleasant. “High doses of vitamin C may cause diarrhea or stomach upset,” says Robert H. Shmerling, MD. “There have also been concerns that high-dose vitamin C supplementation may interfere with blood thinners or cholesterol-lowering medications.” The recommended upper limit for vitamin C intake for adults is 2,000 milligrams per day. Consuming more than this amount can lead to side effects such as nausea, diarrhea, abdominal cramps, and even more serious issues like kidney stones in some cases. While vitamin C is water-soluble, meaning excess amounts are typically excreted through urine, very high doses can still cause gastrointestinal discomfort and may interfere with certain medications.
Vitamin A and E Supplements
ShutterstockVitamin A and E supplements are linked to concerning health outcomes. “A 2012 review of research published in the Cochrane Database found that taking daily vitamin E supplements may increase the risk of dying prematurely,” says Donald Hensrud, MD. “Vitamin A — The same review found large doses of vitamin A supplements were also associated with an increased risk of dying prematurely.” It's crucial to stick to recommended dosages to avoid these potential dangers.
Beta-Carotene Supplements
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Beta-carotene supplements can be very dangerous. “Supplementation with beta-carotene, a compound that's converted to vitamin A by the body, was also shown to increase risk of death, especially for smokers or former smokers,” says Dr. Hensrud. “Since vitamin A deficiency is rare in the U.S., it's probably not worth the potential risk to take this supplement.”
Vitamin D
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While vitamin D supplements are important for those with deficiencies, taking excessively high doses can be dangerous. "High doses of vitamin D can cause severe symptoms, such as stomach upsets, kidney injury, and pancreatitis, and may even be life-threatening," says Dr. Shmerling. Generally, doses above 4,000 IU per day are considered too high for most people, and prolonged use of extremely high doses, such as 10,000 IU or more, can lead to vitamin D toxicity, resulting in serious complications like hypercalcemia (excess calcium in the blood), kidney damage, and other health issues. It's essential to follow medical advice on supplementing vitamin D based on individual needs.
Niacin
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Niacin is readily available but should not be taken without talking to a doctor. “Vitamin B-3 (niacin)....High doses can help lower high cholesterol levels, but this should be done only under the supervision of a doctor. Side effects, including severe liver disease, can occur,” says Dr. Hensrud. While niacin can be beneficial for some, taking doses above 2,000 to 3,000 milligrams per day can lead to serious side effects, including severe liver damage, gastrointestinal issues, and skin flushing. It's important to only take high-dose niacin under medical guidance to avoid these potentially harmful effects.
