Cyanide lurking in your summer peaches?

Some foods really should have a safe word. They should let you know when things are going too far, when you should stop. For example, if you get out of control with a stone fruit, it might try to poison you.

When writer Hanna Phifer tweeted the question earlier this month, “What’s the weirdest thing a client has ever asked you?” Content creator Henny immediately blew it out of the park with a shocking, viral reaction. “A woman asked me to mix cherry pits into her son’s smoothie,” they wrote. “I explained that Pit fruit contains cyanide compounds that can be literally deadly if crushed and ingested. She yelled at me for refusing to do what she asked and for contact with the regional manager.

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It’s a darkly entertaining story, perfectly told, an anecdote that feels right at home in a Knives Out sequel or a Shirley Jackson novel. And its accuracy makes it all the more terrifying. The insides of cherry pits and other stone fruits like peaches and plums actually contain a chemical called amygdalin, which converts to cyanide when ingested. “Not a day goes by,” Henny added, “that I don’t think about how this woman tried to make me an accomplice in the murder of her son.” But how deadly would that smoothie have been exactly? How bad would it be – not just for my Vitamix – if I accidentally dropped a whole fruit in the blender this morning?

If you unknowingly swallow a whole cherry pit because your French friend insists, it’s not like that Yes, really Clafoutis If you don’t spit up seeds at dinner time, don’t lose sleep over it. The worst that’s likely to happen is an uncomfortable experience if that pit completes its journey through your digestive system intact.

It’s not the pit itself that’s the problem. It’s the components inside – so crushing, grinding, or chewing the kernels increases the risks. The same warning applies to other pits from other fruits, such as apples and pears. Children are more susceptible to the effects. If you or your child have any concerns, Healthline advises that you seek immediate medical attention for any symptoms of severe toxicity, including “headache, nausea, seizures, convulsions, and difficulty breathing.”

The good news for the little boy in this Twitter story is that even if his mom had given her smoothie order to a less unscrupulous person, he probably would have been fine anyway. As the National Capital Poison Center explains, “small accidental ingestions generally do no harm.” However, the keyword here is “small”.

There are other common foods that also fall into the not entirely safe category. Potatoes that have turned green or sprouted can contain compounds known as glycoalkaloids, which research from the National Library of Medicine warns can cause diarrhea, nausea, vomiting and other “gastrointestinal upset.” European research has even found that “in severe cases, paralysis, respiratory failure, heart failure, coma and death have been reported.” Just do yourself a favor and ditch all the potatoes with a sketchy hue.

Kidney beans contain a protein called lectin that can cause nausea, vomiting, and diarrhea when eaten raw or undercooked. Even a small amount can make you ill, so cook your beans thoroughly and at a high enough temperature. Mango skin contains a chemical called urushiol, which can cause an allergic reaction similar to poison ivy in some people. Peel your mango. Rhubarb leaves are high in oxalic acid, and eating them can cause shortness of breath, nausea, vomiting, and in rare cases, kidney stones and even death. Stick to the stalks.

Of course, most common sense people would avoid things like green potatoes and raw beans. But what makes this Twitter cherry pit story different is that there really are a lot of people consuming these kinds of things on purpose. In 2017, doctors of a 67-year-old Melbourne man were baffled by the low levels of oxygen in his red blood cells – until they learned he had been taking an apricot kernel supplement as a supposed cancer preventive. As HuffPost reported at the time, “Blood tests showed he had cyanide in his bloodstream at 25 times acceptable levels.”

Memorial Sloan Kettering points out that “although laboratory experiments suggest anticancer properties, clinical evidence does not support this use”, adding that the product “has been linked to several cases of cyanide poisoning in cancer patients”. But the quackery around the core remains, as evidenced by the rampant testimonials for “a highly effective treatment for cancer” on Amazon for a similar product. Things get even more complicated because the apricot kernel extract, properly handled, can be a culinary delicacy. Oh, and did I mention that apricot kernels look almost identical to delicious and non-lethal almonds?

The easiest way to avoid getting sick is to educate yourself and your kids about what fruits — especially seemingly harmless ones — may pose a risk. Regarding fruit, Poison Control advises clearly: “Seeds should never be crushed or chewed. And don’t be ignorant by ever feeding them to your child — or worse, try to force your local smoothie maker to do so.