Weight Watchers' new - and surprisingly effective - points system doesn't take into account how much weight you want to lose
But the calculation at the heart of the company's lauded new program, Beyond the Scale, doesn't actually take members' weight loss goals into account.
The company's calculation plugs these attributes into a widely cited scientific equation to determine members' resting metabolic rate, which is the number of calories their bodies burn per day carrying out basic living functions.
Once Weight Watchers has that number, the company uses it to determine how many calories members should be eating per day in order to lose 1-2 pounds per week.
Even if members want to lose more weight faster, Foster said, the company doesn't support those goals because they're often not safe.
"Losing more has some safety issues with it," he told Business Insider. "We take these things very seriously. We will not prescribe an intake that we do not think is nutritionally adequate."
As members lose weight on the plan, Foster said, they'll get fewer and fewer SmartPoints to eat per day, gradually decreasing the amount of food they're eating to foster weight loss.
What the science says
Participants in a clinical trial on the original plan for a year lost nearly 7 pounds, and an analysis from the company following hundreds of thousands of members found they had 15% greater weight loss with the new program compared to the old one.
Other studies have found Weight Watchers members also tend to lower their heart disease risk and blood pressure, as exercising and losing weight in general have also been shown to do. An interesting analysis (by a researcher who has been a paid consultant for Weight Watchers) found that participants on the plan for a year typically paid $70 per pound lost, but gained $54,130 in quality of life improvement.
So while it may be surprising that Weight Watchers doesn't take into account how much weight members want to lose on the plan, scientifically, it's actually a pretty good thing.