DISCLAIMER: The three supplements that are dangerous if you take too much – causing vomiting, blurred vision and even internal bleeding
Doctors have sounded the alarm about the risks of a handful of supplements 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 mostly in red meat, and vitamin E is abundant in seeds, nuts and fruits and vegetables.
However, experts have warned that some dietary supplement products contain large amounts of these nutrients – meaning it may be easier than you realize to overdose.
Symptoms of niacin overdose include dizziness, nausea, and fatigue
In a report for Discoverco-authored by Texas-based internal medicine physician 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 have only positive health benefits, but very little is known about how they actually work,” said Elena Goun, a University of Missouri chemistry professor. who studies nutritional supplements.
Niacin, or vitamin B3, is a popular supplement that has been recommended for high cholesterol, arthritis and brain function.
The recommended daily amount 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, according to the Harvard TH Chan School of Public Health.
but a series of studies found that niacin did not actually reduce your risk of developing heart disease, stroke, or increase your lifespan, but it was associated with negative side effects such as diarrhea and 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.
Taking more than 35 milligrams (mg) a day makes you more likely to have harmful effects, especially if taken over a long period of time, according to Harvard. Some side effects may include itching, reddened skin, dizziness, nausea, stomach upset or tiredness.
Dietary supplements available online package as much as 50 mg in a daily dose.
Vitamin A is a supplement that has been 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 3000 micrograms per day, you may be at risk of toxicity.
DailyMail.com found some products containing up to 7,500 micrograms in one pill.
“Vitamin A toxicity may be more common in the United States than a deficiency due to high doses of preformed vitamin A (retinol) found in some dietary supplements” according to Harvard TH Chan School of Public Health.
If you take too much vitamin A, you may develop bone pain, nausea, vomiting, dry skin, blurred vision and sensitivity to bright light.
In the long term, researchers have also linked the intake of vitamin A and similar forms, such as beta-carotene, to an increased risk of lung cancer– especially if you were a former smoker.
Many types of supplements contain far more than your recommended daily intake, experts say, which can increase the risk of you taking too much of the nutrients
Vitamin E is a supplement that has been recommended for its immune boosting effects. It is found naturally in nuts such as peanuts and almonds, seeds and some fruits such as mango and kiwi.
NIH recommends adult men and women consume 15 mg of vitamin E per day – either through diet or supplements.
If you take more than 1,000 milligrams of the nutrient, you may be at risk of developing vitamin E toxicity — which manifests itself in muscle weakness, diarrhea and nausea.
The more common risk of taking vitamin E is that it acts a bit like a blood thinner, according to Merck. So if you are injured while taking this drug, you may bleed, internally or externally, much more than you would naturally.
If you take too much vitamin E, you may have an increased risk of internal bleeding, or you may just see some unpleasant side effects, such as diarrhea
In rare cases, the NIH reports that vitamin E has led to life-threatening bleeding — including making the fallout from strokes worse. A study from Harvard Medical School reported that taking vitamin E increased the likelihood of developing a bleed by 22 percent.
In addition to the three particularly dangerous supplements, there are other things to be aware of in this sphere-like multivitamin.
These products may contain ‘amounts of some vitamins and minerals that are significantly higher’ than the daily recommended amount, and may even reach dangerous levels, according to the NIH.
There are also some dietary supplements that interact with prescription medications.
For example, taking herbal supplements St. John’s wort can make contraception ineffective. So experts recommend talking to your doctor before starting a new supplement regimen.
With all of this in mind, dietitians recommend getting your nutrients from a well-balanced diet whenever possible.