To Lose Weight, You Need to Burn 7000 Calories, Not 3500
For a daunting task like trying to lose weight, it’s nice to rely on math and logic to figure out how to do it. For example, if you’ve ever calculated how much weight you will lose by eliminating a certain number of calories per day, you know the most famous diet equation: one pound of fat = 3,500 calories. Too bad the equation is wrong .
This might be correct in a strict mathematical sense, for example if you are burning a pound of fat in a lab, but cutting 500 calories a day for a week will not lose a pound of fat. We’ve talked about this before: trying to balance your calorie intake and burning never works .
Now, the city has a new equation, or rather a calculator called Body Weight Planner , based on research conducted by the National Institutes of Health . Amby Burfoot explains in Runner’s World why we must abandon the old rule and embrace the new:
“The biggest drawback of the 500 calorie rule is that it assumes weight loss will be linear over time,” says [mathematician Kevin] Hall. “The body doesn’t react to it. The body is a very dynamic system, and a change in one part of the system always brings about changes in other parts. “
What’s real? In the first year of the new weight loss program, most overweight people will lose about half the weight predicted by the 3500 calorie rule, Hall said. In other words, for 12 months, the new rule is 7,000 calories = one pound. (The math changes slightly over shorter and longer periods of time, and only a few manage to lose weight after 12 months.)
Of course, the results will differ from person to person.
And the new figure may sound daunting at first, but long-term dieters may feel validated: Science has finally confirmed what your body has already told you. It’s not that you’re not working hard enough – it’s just that we were given the wrong equation.
This story was originally published on 7/22/15 and updated on 10/10/19 to provide more complete and up-to-date information.