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Taking Too Much of This Common Supplement Can Cause Hair Loss, Joint Pain, and Fatigue

You don't want to overdo it with this one.


Eating a diet rich in vitamins and minerals can help fight infections and inflammation, and taking supplements to ensure you’re getting enough of the right ones can act as an extra shield of protection for your health. However, getting too much of certain vitamins and minerals can actually have a negative effect. Selenium is one of those minerals. When taken correctly, it has several benefits. But overdoing it can lead to hair loss, fatigue, and other scary symptoms.

What is selenium?

Selenium is a key component of several enzymes and proteins called selenoproteins, which help protect against cell damage. It’s found in foods like Brazil nuts, chicken, and whole wheat bread, and is available in supplement form as well.

While your body only needs a small amount of selenium to function (it’s known as a “trace mineral” for this reason), taking a selenium supplement can have numerous benefits. It helps neutralize free radicals in the body that might otherwise cause oxidative-stress related illnesses like heart disease and Alzheimer’s. Also, it works to rev up your metabolism for improved thyroid health and quicker weight loss. Sounds great, right? But use caution: Taking too much selenium can have some pretty dangerous (not to mention unpleasant) side effects.

How much selenium is toxic to humans?

According to the National Institutes of Health, adults 51 to 70 years of age can take 55 micrograms of selenium per day. This recommended dosage will help prevent selenium deficiency, which can cause weight gain and lowered immunity against common viruses. But they warn against taking 400 micrograms or more of the mineral a day, which can be toxic.

What happens if you have too much selenium in your body?

The effects of taking too much selenium (also called selenium toxicity) over time will be very apparent. A study published in Archives of Internal Medicine found that common symptoms of selenium toxicity include nausea, fatigue, hair loss, diarrhea, joint pain, and nail brittleness and discoloration. Researchers added that people who take excess amounts of selenium in their system might also have “garlic breath” — when they haven’t even eaten any garlic! Yuck.

If you have any of these symptoms and are worried they might be due to your selenium intake, see your doctor. (Or really, even if you have these symptoms and don’t take selenium!) And if you have questions about selenium supplementation in general, check with a health professional to see if it might be a good addition to your daily routine. This way you can get all of the benefits from this powerful mineral without any of the negative side effects.

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