Question: how many calories in a us envelope?
Answer: Fat Loss School suggests an envelope has around a thousandth of a gram of gum arabic, while DietFacts estimates that a U.S. postage stamp accounts for a tenth of a calorie. The U.K. Royal Mail, in one estimate to The Guardian, says that its stamps range from 5.9 calories to 14.5 calories. Don't fill up on stamps.