That's right, we're recommending that you ditch your digital scale with the two decimal places. When dieters at the University of Utah received a “health index score” that was pleasingly vague—a weight range rather than an actual number—they lost up to four pounds in just three weeks. In contrast, when participants received their score in the form of an exact number, they gained up to a pound on average. The fuzzier the feedback, the more room there was to interpret it optimistically, the study concluded. (“Almost there!”) As a result, the goal seems more achievable—and we become more motivated. On the flip side, a precise number makes us aware of when we're not doing well—which all too often drives our discouraged self to lapse or quit.
The lesson: If you weigh yourself daily, even normal fluctuations could throw you off. Instead, get on the scale weekly and use a range as a goal (“I'd like to lose 5 to 10 pounds this year”).