hohonium
A theoretical, radioactive element (chemical symbol HoHo), which is theorized to be present in Hostess-brand snack cakes (Twinkies, Ho-Hos, Ding-Dongs, etc.) The presence of Hohonium would explain why these foods have a half-life, rather than a shelf-life.
Thanks to the miracle of Hohonium, we don't need to worry about our Twinkies ever going stale.