Mentions of radioactivity can send the mind in a dramatic direction, but many ordinary items are technically radioactive โ including the humble banana. Radioactivity occurs when elements decay, and for bananas, this radioactivity comes from a potassium isotope called K-40. Althoughย it makes up only 0.012%ย of the atoms found in potassium, K-40 can spontaneously decay, which releases beta and gamma radiation. That amount of radiation is harmless in one banana, but a truckload of bananas has been known toย fool radiation detectorsย designed to sniff out nuclear weapons. In fact, bananas are so well known for their radioactive properties that thereโs even an informal radiation measurement named theย Banana Equivalent Dose, or BED. 
So does this mean bananas are unhealthy? Wellโฆ no. The human body always stores roughly 16 mg of K-40, which technicallyย makes humans 280 times more radioactiveย than your average banana. Although bananas do introduce more of this radioactive isotope, the body keeps potassium in balance (orย homeostasis), and your metabolism excretes any excess potassium. Oh, and in case you were wondering, a person would have to eat many millions of bananas in one sitting to get a lethal dose (at which point youโd likely have lots of other problems). So go ahead and eat that banana cream pie โ you can leave the Geiger counter at home.
Media Release/Interesting Facts
