Bananas are suddenly back in the spotlight thanks to a viral video by nuclear engineer Tyler Folse. On his Instagram reel, he breaks down a fun but very real scientific fact. Bananas contain a tiny amount of radioactive potassium. His light hearted explanations have sparked huge curiosity about how radiation works in everyday life.
Folse starts by answering the internet’s favourite question. Are bananas actually radioactive?
“They contain trace amounts of potassium forty. The key word is trace,” he says. He explains that the amount is so small “your body will not even notice it.”
Potassium forty is a naturally occurring isotope. Every banana has it. Every human body has it too. Folse reminds viewers of that with a laugh. “You are already radioactive. The body contains elements that are radioactive, including potassium.”
More importantly, your system keeps these levels in check. “Eating bananas will not make you radioactive because your body regulates it. Extra potassium would just get flushed out,” he says.
To make the concept easier to understand, Folse uses the playful unit that scientists often joke about. The banana equivalent dose.
“Measured in bananas, flying from New York to London would be like eight hundred bananas,” he says. One banana equals roughly 0.1 microsieverts. It is a tiny number.
A microsievert is a tiny unit used to measure the health impact of radiation exposure, commonly used in studies of everyday radiation exposure and safety.
Medical scans and daily life expose people to much more radiation. “A single chest X ray is like a thousand bananas,” Folse notes. “And every year, just by being out in the world, Americans get a dose of sixty two thousand bananas worth of radiation.”
Smoking increases that exposure even more. “Smoking a pack of cigarettes every day for a year would expose you to two hundred forty thousand bananas,” he explains. Tobacco contains small amounts of lead-210 (²¹⁰Pb) and polonium-210 (²¹⁰Po). “It is not the most hazardous aspect of smoking, but you are starting to get measurable at this point.”
Online viewers often ask how many bananas it would take to get sick. Folse answers that with a simple comparison.
“To actually feel radiation sickness, it would take about ten million bananas,” he says. At that point a person would suffer potassium poisoning long before radiation caused any problems.
The numbers become even more extreme when people ask about lethal levels. “Lethal dose of radiation would only happen at about fifty million bananas,” Folse says.
Folse ends the reel with a surprising fact about our own bodies.
“The weirdest part of all is that you, right now, are already two hundred eighty times more radioactive than a banana,” he says. We naturally carry potassium forty and other trace isotopes.
This is because the human body contains far more total potassium—including potassium-40—than a single banana.
Even close contact with another person gives a tiny dose. “You get a dose cuddling your spouse. It depends on how long you cuddle and how hot your spouse is,” he jokes.
With all this in mind, bananas remain one of the safest—and funniest—ways to learn about radiation.
(Rh/ARC/MSM)
