brazil nuts, selenium

Q. My wife is always telling me not to eat so many Brazil nuts. The last 10 days I have eaten more than usual, up to six a day. I probably ate at least 40 nuts. I estimate that batch contained up to 6 mg of selenium, which is way too much.

I have noticed a metallic taste in my mouth. That’s a known symptom of selenium toxicity, so I am going to stop for a while and not OD in the future!

A. Your wife is right about not pigging out on Brazil nuts. Brazil nuts are high in selenium and an ounce (roughly half a dozen) provides 800 micrograms. That’s about double the US recommended tolerable upper limit. Overindulging regularly could lead to selenium toxicity. Symptoms may include a metallic taste, garlic odor on the breath, hair loss, brittle nails, fatigue, nausea, rash, diarrhea, runny nose, cough and nerve pain. Selenium-containing supplements are another potential source of this mineral.

It's almost Black Friday at The People's Pharmacy!

Black Friday at People's Pharmacy 2017
View Specials Now

Get The Graedons' Favorite Home Remedies Health Guide for FREE

Join our daily email newsletter with breaking health news, prescription drug information, home remedies AND you'll get a copy of our brand new full-length health guide — for FREE!

  1. Donald

    I ate a lb of nuts and now my toilet glow in the dark , should I be concerned ?

  2. Ashfaq


    For a few weeks I consumed many brazillian nuts, some days more than 20 nuts and some days less plus other nuts like walnuts, hazelnuts – I am observing bump type of pimples on back of my head since few weeks. Also type of flu which is not going away.
    Can I link these with nuts? If so, do I need a treatment?

  3. cpmt

    Chilbob… what are you talking about? I don’t understand your comment (sorry I must be dumb today or brain fog). Please explain

  4. Chilibob

    Some people get freaked out about possible ingestion of radiation. Most people know bananas contain the potassium isotope (naturally occurring). What they don’t know is that brazil nuts contain 5 times the level of bananas. The element in the spotlight here is Radium. Look it up…

  5. M

    Ooooops just ate about 15 :( they were big too!

  6. Mara

    Hmm interesting. Confession time! I went to the market on an empty stomach and bought 50 grams of Brazil nuts, usually I have 2 a day but not today. Over the course of 3 hours whilst running around doing chores and what not I consumed this whole 50 gram bag. Oh my. Now what?

  7. may

    I’ve read (or heard) that macadamia nuts also are a good source of selenium but not as much selenium as contained in Brazil nuts.

  8. cpmt

    I read in a government website the you should not eat more than 2 or 3 a day.

  9. Kay

    Great information. I just bought a big bag of brazil nuts from Trader Joe’s and have been having 4 or 5 a day.

  10. NDF

    The NIH only lists brazil nuts as a source that is extremely high in selenium. It is a source that is over 30 times higher than the next listed source, in that 1 oz gives nearly ten times higher levels than 3 oz of tuna, the next most concentrated source.

  11. Noah T.

    I am not an expert and constantly on the heels of Joe and Terry. From what I remember brazil nuts are the only one.

  12. Deon

    What about those of us who are “nuts” about other nut species too? Is the selenium a problem that is restricted to Brazil nuts?

What Do You Think?

We invite you to share your thoughts with others, but remember that our comment section is a public forum. Please do not use your full first and last name if you want to keep details of your medical history anonymous. A first name and last initial or a pseudonym is acceptable. Advice from other commenters on this website is not a substitute for medical attention. Do not stop any medicine without checking with the prescriber. Stopping medication suddenly could result in serious harm. We expect comments to be civil in tone and language. By commenting, you agree to abide by our commenting policy and website terms & conditions. Comments that do not follow these policies will not be posted.

Your cart

Shipping and discount codes are added at checkout.