Why land on 2,000 calories?
Doctors didn't just pull it out of thin air, did they? Of course not! They used (finger quotes) SCIENCE. Although a male college athlete's caloric needs vastly differ from those of a postmenopausal woman, for example, there's no way all those different benchmarks would fit on the side of a cereal box. So the FDA decided to go for a middle-ground approach. "The FDA wanted a single number so their recommendations would be simple to follow, and also they did not want to encourage overeating," Dr. Quebbemann says.
The FDA arrived at 2,000 using surveys of how much food people consumed per day, Dr. Quebbemann says. This ranged anywhere from 1,600 calories to 3,000 calories. It averaged the data and came up with a single number, which was… not 2,000. The FDA initially proposed setting the daily value at 2,350 calories, which gives you at least an extra snack, but decided on lowering the amount to 2,000 after asking for public comments and deciding that anything above 2,000 might encourage people to overeat. Which probably isn't a bad assumption, knowing Americans, even though going down to 2,000 is a significant reduction.