It may come as a shock to you but some of the food that we eat is radioactive. Bananas are one such food. They contain about 450mg of potassium, some of which is potassium-40 which is, you heard it here first, radioactive. In fact, 50 bananas are about as radioactive as a dental x-ray.

But before you don your lead suit, we’ll break more bad news for you. Spinach, potatoes, oranges, some nuts, and your very own body are also radioactive. In fact, radiation is all around us. Everything in the world is composed of elements. Some of these elements have unstable atoms that decay over time, emitting radiation in the form of subatomic particles, such as electrons, alpha particles, and neutrons, or electromagnetic waves, like gamma rays. As with chemical toxins, how deadly this radiation is depends on the radioactive element, its amount, our distance from the source, and the length of time you were exposed (has to be at least a bananosecond).

Radioactive potassium in bananas

The element Potassium (K) is found in bananas but only a tiny amount (the Potassium-40 atoms) are radioactive. These radioactive K-40 atoms break down on their own, giving off beta radiation and gamma rays. Both types of radiation can hurt tissues. However, K-40 isn’t very radioactive, and it takes 1.3 billion years for half of it to break down meaning, only a few thousand atoms break down each second.

Will I die of radiation exposure if I eat bananas my entire life?

Do bananas pose a health risk if you eat them often throughout your life? Some people think they do because bananas contain radioactive Potassium-40 but our bodies already have potassium in them naturally and our metabolic system is designed to keep the levels stable. The amount of radioactive potassium in bananas is not enough to cause any harm. In fact, we get exposed to more radiation when we sleep next to someone than we do from eating bananas (honey, could you scoot over a little bit?).

So, break it to me easy, how many bananas will it take to kill me with radiation?

How many bananas would it take to kill us with radiation? Consider this. One thousand bananas are equivalent to a chest x-ray. 70,000 bananas equal a chest CT scan. A typical radiotherapy session hits you with about 20,000,000 bananas. So according to our calculations (and we feel compelled to remind you, we *are* geniuses), about 100 million bananas would equal a lethal radiation dose of 10,000,000 uSv – unless of course we left off a zero or forgot to carry a 1. So the point is – feel free to eat as many bananas as you’d like – but you might seriously consider asking your significant other to sleep in another room.