Bananas contain natural levels of radioactivity that have turned them into an informal scientific unit of measurement.
This tropical fruit contains potassium-40, a naturally occurring radioactive isotope that makes up approximately 0.012% of all potassium present in bananas. An average banana emits about 0.1 microsieverts of radiation.
Scientists have coined the term 'Banana Equivalent Dose' (BED) to help the public understand radiation levels. For example, a dental X-ray is equivalent to eating 50 bananas, while a transatlantic flight is equivalent to 400 bananas.
Curiously, eating bananas can trigger radiation detectors at airports and nuclear plants. However, the amount is completely safe: you would need to eat 10 million bananas at once to suffer radiation poisoning, which would be physically impossible.
Source: Nuclear Physics Review
