Yet as a rare-substance being, you are also composed of the most common elements of the rarest substance that is baryonic matter: Carbon, Oxygen, Hydrogen, and Nitrogen. Along with a song and dance of other things...INCLUDING ANTIMATTER.
Within your body is about 100 grams of potassium--about the same mass a banana weighs. Out of all populations of potassium in the universe, .0117% of that population of potassium is Potassium-40, which is radioactive. /2
This means that you contain 11.7 milligrams of radioactive potassium-40. To put this into perspective, 220 times that weight equals the mass of a post-1982 penny. /3
The decay of Potassium-40 often results in the emission of an anti-electron, an antimatter particle, once every 75 minutes of your life, give or take. The anti-electron eventually bumbles into a normal electron and they both annihilate and release some gamma ray photons. /4
This means all you mortals are on the road to becoming the Incredible Hulk. /5 
