Doctors have sounded the alarm about the risks of a handful of supplements that may be lurking in your medicine cabinet.
Vitamin A, vitamin B3, also known as niacin and vitamin E, can be dangerous in large amounts, leading to nausea, bone pain and even internal bleeding.
A balanced diet contains all these nutrients in small amounts. Vitamin A is found in green leafy vegetables, milk and eggs, vitamin B3 is mainly found in red meat and vitamin E is abundant in seeds, nuts, fruits and vegetables.
However, experts have warned that some supplements contain high amounts of these nutrients, meaning it could be easier than you think to overdose.
Certain supplements can have unpleasant and potentially dangerous side effects, such as blood thinning, which is associated with an increased risk of bleeding.
In a report for To discoverco-authored by Texas-based internist Dr. Ahmad Talha Azam, the three vitamins above are highlighted as potentially harmful due to the risk of taking too much.
“Some people take them [vitamins and supplements] because they automatically assume that vitamins and supplements only have positive health benefits, but very little is known about how they actually work,” says Elena Goun, a professor of chemistry at the University of Missouri who studies supplements.
Niacin, or vitamin B3, is a popular supplement recommended for high cholesterol, arthritis and brain function.
The recommended daily allowance of niacin is 16 mg for men, 14 mg for women and 18 mg for pregnant women.
Niacin used to be recommended for people at risk of developing heart disease Harvard TH Chan School of Public Health.
But one series of studies found that niacin did not actually reduce your risk of developing heart disease or stroke or increase your lifespan, but it was associated with negative side effects such as diarrhea and skin flushing.
Other forms of vitamin B3, such as the popular anti-aging supplement nicotinamide riboside, have been linked to an increased risk of brain cancer.
If you take more than 35 milligrams (mg) per day, you’re more likely to experience harmful effects, especially if you take it over a longer period of time, according to Harvard. Some side effects may include itching, red skin, dizziness, nausea, stomach upset, or fatigue.
Supplements available online package as much as 50mg in a daily dose.
Symptoms of a niacin overdose include dizziness, nausea, and fatigue
Vitamin A is a supplement recommended for eye health and to support the immune system.
The FDA recommends about 900 micrograms of vitamin A per day for men and 700 micrograms for women. If you take more than 3,000 micrograms per day, you may be at risk for toxicity.
DailyMail.com has found a number of products that contain up to 7,500 micrograms in one pill.
“Vitamin A toxicity may be more common than deficiency in the US, due to high doses of preformed vitamin A (retinol) found in some supplements,” the statement said. Harvard TH Chan School of Public Health.
If you take too much vitamin A, you may experience bone pain, nausea, vomiting, dry skin, blurred vision and sensitivity to bright light.
In the long term, researchers have also linked taking vitamin A and similar forms, such as beta-carotene, to an increased risk lung cancer– especially if you were previously a smoker.
Many types of supplements contain much more than your recommended daily allowance, experts say, which could increase the risk of getting too much of the nutrients
Vitamin E is a supplement recommended for its immune-boosting effects. It occurs naturally in nuts such as peanuts and almonds, seeds and some fruits such as mango and kiwi.
The NIH advises Adult men and women consume 15 mg of vitamin E daily, either through diet or as a supplement.
If you take more than 1,000 milligrams of the nutrient, you may be at risk for developing vitamin E toxicity, which manifests as muscle weakness, diarrhea and nausea.
The more common risk of taking vitamin E is the fact that it acts a bit like a blood thinner. according to Merck. So if you are injured while taking this medication, you may bleed much more internally or externally than you would naturally.
If you take too much vitamin E, you may be at increased risk of internal bleeding, or you may experience unpleasant side effects such as diarrhea.
In rare cases, the NIH reports that vitamin E has led to life-threatening bleeding, including worsening the effects of strokes. A study from Harvard Medical School reported that taking vitamin E increased the risk of bleeding by 22 percent.
In addition to these three particularly dangerous supplements, there are other things to watch out for in this area, such as multivitamins.
These products may contain “amounts of some vitamins and minerals that are substantially higher” than the daily recommended amount, and may even reach dangerous levels, according to the NIH.
There are also some supplements that interact with prescription medications.
For example, you can take the herbal supplement St. John’s wort birth control not effective. Therefore, experts recommend talking to your doctor before starting a new supplement regimen.
With all this in mind, dietitians recommend getting your nutrients from a well-balanced diet whenever possible.