Eating too many Brazil nuts could trigger a raft of alarming health problems, a leading dietitian has revealed.
Abbey Sharp took to her social media channels claiming ‘this is not a drill, folks… so few people know about this, but [eating too many] can be deadly’.
Canadian Ms Sharp, 37, who has two million followers across TikTok, Instagram and YouTube, said the key concern was selenium.
The mineral aids fertility and metabolism and is found in a variety of foods such as eggs, fish, mushrooms and turkey — but Brazil nuts are by far the richest source.
Just 1oz — six to eight — Brazil nuts contains roughly 1,000 per cent of the recommended daily amount of selenium — meaning it’s very easy to overdose, according to Ms Sharp.
‘The upper limit for selenium is 400 micrograms, and it only take seven nuts to cross that threshold,’ she added. ‘And obviously much fewer for a child.’
In the post, which has been viewed more that 1.5million times in Instagram alone, she lists the downsides of consuming excessive amounts of selenium.
‘Toxicity symptoms can range from garlicky breath — gross — diarrhoea, brittle nails, up to life threatening symptoms like kidney and heart failure.
Dietitian Abbey Sharp took to her social media channels claiming ‘this is not a drill, folks… so few people know about this, but [eating too many Brazil nuts] can be deadly’
Canadian Ms Sharp, 37, who has two million followers across TikTok, Instagram and YouTube, said the key concern was selenium
‘I feel like Brazil nuts should be sold with a clear warning on the front and really should be treated more like a supplement than a snacking food.
‘So lets just stick with the peanut mix for parties and keep those Brazil nuts in the cabinet where they belong.’
The National Institutes of Health, Office of Dietary Supplements, in the US, provides details advice on selenium.
It states ‘you can get recommended amounts of selenium by eating a variety of foods, including seafood, meat, poultry, eggs, and dairy products, breads, cereals, and other grain products’.
Studies suggest that people who lower amounts of selenium could have an increased of developing a range of cancers, but the guidance warns: ‘Whether selenium supplements reduce cancer risk is not clear.’
Under the subheading ‘Can selenium be harmful?’ it states: ‘Yes, if you get too much. Brazil nuts, for example, contain very high amounts of selenium and can cause you to go over the upper limit if you eat too many.
‘Extremely high intakes of selenium can cause severe problems, including difficulty breathing, tremors, kidney failure, heart attacks, and heart failure.’
Other experts have suggested limiting Brazil nut consumption to two-to-five per day is safe.
‘I feel like Brazil nuts should be sold with a clear warning on the front and really should be treated more like a supplement than a snacking food,’ said Ms Sharp
In 2006 an Australian man, aged 75, died after consuming a large number of selenium supplements.
According to a report in the Medical Journal of Australia, he had become concerned about prostate cancer and read online that selenium played a role in preventing the disease.
In a 2020 study review experts at The National Research Centre For The Working Environment in Denmark outlined a number of cases of severe illness and death due to selenium poisoning.
The patients all had ingested a liquid chemical called gun bluing agent, which is primarily used to colour metals — such as those guns are made of — black.
It contains selenium dioxide, which is made by burning selenium. 
Brazil nuts do not contain this form of selenium, and the deaths are not linked to consuming Brazil nuts.
However they serve as a stark warning as to how toxic very large amounts of selenium can be.
The reports included a 24-year-old man and two women, one aged 40 and another 54, who all suffered a fatal cardiac arrests just hours after ingestion of gun bluing agent.
The National Institutes of Health states ‘you can get recommended amounts of selenium by eating a variety of foods, including seafood, meat, poultry, eggs, and dairy products, breads, cereals, and other grain products’
There were also numerous tragic reports of toddlers who had consumed the liquid and rapidly died, including a 22-month-old boy.
He had been taken to the emergency room and ‘initially, he was pink, alert, and combative, but his condition rapidly deteriorated.
‘His mental status deteriorated, he had to be ventilated and he became cyanotic [when the skin becomes blue], unresponsive, and without a palpable pulse.
‘He developed ventricular fibrillation [an abnormal heart rhythm] and died.’
The daily upper limits for selenium include intakes from all food sources are:
Birth to 6 months – 45 mcg
Infants 7–12 months – 60 mcg
Children 1–3 years – 90 mcg
Children 4–8 years – 150 mcg
Children 9–13 years – 280 mcg
Teens 14–18 years – 400 mcg
Adults over 18 – 400 mcg
*Source: The National Intitutes of Health
Brazil nuts contain very high amounts of selenium — between 68 and 91 mcg per nut.
A slice of whole wheat bread contains 13 mcg of selenium, while a portion of sardines or shrimp contains roughly 45mcg.
A skice of wholegrain bread contains 13mcg.
