Brazil Nuts’ Superpower


Bring in the new year by starting a new habit that will benefit your health. It’s not even a hard one, so you can actually keep this year’s resolution! Just eat one Brazil nut every day (but not more than that) to ensure that you are taking in enough selenium in your diet. This powerful nutrient is an essential mineral found to have a profound effect on our health! It’s critical in protecting us from toxins and fighting diseases.

Offering the most concentrated source of selenium, one Brazil nut provides a full day’s amount of selenium (from 40 to 90 mcg per nut) depending on the size and growing soil. Seafood is also rich in selenium. But one Brazil nut has as much selenium as three ounces of tuna.

Research studies have found that the selenium in seafood protects against adverse effects of mercury and other metals that can be toxic to the body. According to Dr. Nick Ralston, a leading researcher in mercury toxicity, there is enough selenium in most seafood to neutralize the mercury. So you can worry less about metals in seafood, and focus more on taking advantage of the other valuable nutrients found in seafood.

Brazil nuts are actually seeds of this 5 pound nut that resembles a coconut and holds 12–20 seeds.

Making sure that we have enough selenium in our diets helps our bodies to combat toxins. Selenium recycles and restores many vital antioxidants (like vitamin C and E) to their active forms, protecting against damage in vulnerable tissues like the brain. Selenium prevents and reverses cell damage throughout the body. All cells need selenium, and there is no substitute for it in the body.

Besides selenium’s critical role in neutralizing harmful substances and controlling cell damage, it appears to fight disease in other ways as well. Many chronic diseases are inflammation-based. Selenium is involved in the production of prostaglandins that regulate inflammation, positively influencing the body. Selenium appears to stimulate the body’s immune responses to invaders (including viruses like the flu) to prevent or stop illnesses. More research is needed in this area, but it appears that selenium helps prevent and slow the development of cancer and cardiovascular disease, as well as boost brain function, fertility, and possibly our mood.

Selenium plays a significant role in healthy thyroid function which regulates much of our metabolism. A selenium-containing enzyme is responsible for transforming a less active thyroid hormone called T4 into the more active T3. Researchers have found problems develop with the thyroid gland in just two months of a low-selenium diet.

Stay with a natural, whole food method to consistently consume this powerful mineral, rather than selenium supplements, which have been shown to cause problems. But a word to the wise: more is not always better. That is especially so in the case of selenium. While some selenium is critical, too much is problematic. High levels of selenium over a long period leave a metallic taste in the mouth, cause garlic odor in the breath, hair and nail loss, rashes, diarrhea, or fatigue. An excessive intake of selenium in supplement form has been found to raise the risk of type 2 diabetes.

Given that Brazil nuts are the most concentrated source of selenium, don’t go crazy and stick to just one serving, or at the most two servings per day, here and there, if you’re not a seafood fan. If you do eat a lot of seafood, only eat a Brazil nut on the days you don’t have seafood, to be extra careful. However, unlike supplements, consuming nutrients in whole food form give us some wiggle room. It’s difficult to “overdose” on selenium when it naturally occurs in foods. But don’t snack on Brazil nuts like peanuts, either!

In fact, check any vitamin and mineral supplement you might be taking to see how much selenium it contains. The Recommended Dietary Allowance (RDA) of selenium for adults is 55 micrograms, and 400 micrograms per day or more is the upper limit. If your supplement contains selenium, be aware of the amount. It’s so much better to get this particular nutrient in whole foods, but 55 micrograms (or 60 mcg for pregnant woman and 70 mcg for lactating women) in a supplement shouldn’t be a problem either, assuming your remaining selenium intake is coming from whole food sources.

Because selenium is so critical to our health, it’s worth making an effort to buy Brazil nuts and always have them at home, especially if seafood is not a big part of your diet. Brazil nuts are also high in protein, fiber, thiamine, copper, magnesium, phosphorus, zinc, manganese, and vitamin E. I buy raw, shelled Brazil nuts from Trader Joe’s and leave them in an easily accessible place. Take my January’s Healthy Challenge and start eating one Brazil nut every day to ensure that your body is equipped to fight off disease.


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A Daily Brazil Nut Better than a Supplement for Selenium