Brazil nuts, dangerous?

[Fit4meee]

After checking my graph, I found out that 1 brazil nut contains 115% RDI of selenium!!! The other day I unknowingly had around 2350% of the mineral . These nuts should come with a warning

[VitoVino]

Good tip. Who wudda thunk?

[VitoVino]

You're totally correct, these nuts should come with a warning.

According to the National Institutes of Health, abnormally high levels of selenium in the blood can cause a condition called selenosis, characterized by symptoms such as hair loss, garlic breath odor, white blotchy nails, gastrointestinal problems, irritability, fatigue and nerve damage. The effects of selenium poisoning are similar to the symptoms of arsenic poisoning, though symptoms may vary depending on factors such as the type of selenium ingested as well as the dose. Other symptoms of selenium toxicity include lightheadedness, facial flushing, tremor, muscle tenderness, liver and kidney problems and blood clotting problems.

And just one ounce of them have 776% the RDA of selenium. But other than all that, they're very healthy!

[Rubystars]

You know guys the RDA (based on a 2000 calorie diet) is not the end all and be all. I think the number you would need to consider would be the LD50 for Selenium or at least find out what a toxic dose is. Have you read anything that said selenium is dangerous from a whole food source like Brazil nuts?

[VitoVino]

Originally Posted by Rubystars

You know guys the RDA (based on a 2000 calorie diet) is not the end all and be all. I think the number you would need to consider would be the LD50 for Selenium or at least find out what a toxic dose is. Have you read anything that said selenium is dangerous from a whole food source like Brazil nuts?

Linus Pauling Institute:

Toxicity

Although selenium is required for health, like other nutrients, high doses of selenium can be toxic. Acute and fatal toxicities have occurred with accidental or suicidal ingestion of gram quantities of selenium. Clinically significant selenium toxicity was reported in 13 individuals after taking supplements that contained 27.3 milligrams (27,300 mcg) per tablet due to a manufacturing error. Chronic selenium toxicity (selenosis) may occur with smaller doses of selenium over long periods of time. The most frequently reported symptoms of selenosis are hair and nail brittleness and loss. Other symptoms may include gastrointestinal disturbances, skin rashes, a garlic breath odor, fatigue, irritability, and nervous system abnormalities. In an area of China with a high prevalence of selenosis, toxic effects occurred with increasing frequency when blood selenium concentrations reached a level corresponding to an intake of 850 mcg/day. The Food and Nutrition Board (FNB) of the Institute of Medicine recently set the tolerable upper intake level (UL) for selenium at 400 mcg/day in adults based on the prevention of hair and nail brittleness and loss and early signs of chronic selenium toxicity (15). The UL of 400 mcg/day for adults (see table below) includes selenium obtained from food, which averages about 100 mcg/day for adults in the U.S., as well as selenium from supplements.

[RunbikeSki]

Remember the difference between acute (basically a single dose) and chronic (long term exposure) doses.

Vito's post indicates that one needs to eat grams of Selenium for an acute exposure. A brazil nut has 544 micrograms (1 millionth of a gram) of selenium so you'd have to eat some where around 10 thousand brazil nuts to recieve an acute toxic dose.

Or, you could probably eat 1000 brazil nuts a day for many months to get a chronic exposure.

Selenium is water soluble so it does not generally get stored in the body. You eat a bunch of brazil nuts, blood concentrations are a bit elevated for a while, and then the excess is excreted.

So as long as you are not living on brazil nuts exclusively (or have some other underlying health issue) enjoying a few from time to time is pretty harmless.

Selenium does, however, have some environmental implications:

http://www.northtrinitylake.com/wate...mCaseStudy.pdf

[VitoVino]

Nice post, Pam.

For the record, my post pointed out that 1 ounce of Brazil nuts exceeds the daily upper limit. Eating Brazil nuts every day, in this quantity, long term, seems to suggest that toxicity will occur.

[Fit4meee]

I agree with Vito, it seems that prolonged high exposure, such as 1 ounce a day long term can cause complications. Not to mention, selenium occurs in other foods as well so one would have to only eat these nuts and no other selenium rich foods (chicken, eggs, fish, etc). Not sure if I can post links but on this site Selenium at the bottom it states that we should limit brazil nuts to 2 a day to avoid getting too much selenium. It seems that whether the mineral comes from a whole food or a supplement, it could nevertheless produce undesired effects. I still think they should come with a warning :P I bought a big bag but I'm sticking to 1-3 a day now

[VitoVino]

Nice post, Fit4meee.

And you can certainly post links, links are allowed. Links can even have a "bit" of advertising on them so long as they are not BLATANT hawking of a particular product/service. It's difficult to post a link these days which doesn't have ANY advertising in some way. I know, I've posted them myself.

Finally, we know who our regular members are, and the ones that are new who come here for the sole purpose of spamming.

I may have to start a thread about this topic, for clarification.

[Rubystars]

Well one of the tricks of a healthy diet is to eat a varied diet, so I think this would fall into that category. Eating some extra selenium here and there is probably healthy, but not every day.