New Weight Loss Math Makes Task More Daunting
Experts are weighing in on the old rule-of-thumb that says one pound of fat equals about 3,500 calories.
Sorry, dieters: Recent studies indicate the equation isn't that simple. In the short-term, the formula holds up. But over the long haul, much bigger dietary changes are needed, especially for more overweight and obese people.
On "The Early Show" Wednesday, CBS News Medical Correspondent Dr. Jennifer Ashton explained that there's some new math anyone trying to shed pounds needs to be aware of.
While the formula does work, the research suggests there are many variables. Cutting out 100 calories a day -- the chocolate chip cookie or that soda-- "the small changes" theory -- can help in the short-run, new research suggests weight loss doesn't continue indefinitely.
Special Section: Dr. Jennifer Ashton
Your body's self-regulatory mechanisms kick in. As body size diminishes, so does the amount of fuel needed to maintain and move it, and weight settles at a new steady level. Weight loss produces changes in hormones, the nervous system and the efficiency of the muscles to conserve energy. So, additional weight loss can only happen with a more severe diet or more intense physical activity. And most people do the opposite, after achieving weight loss, resuming their old diet and exercise habits, consequently regaining weight.
The dirty little secret is that, over a long period of time, much bigger dietary changes are needed to gain or lose pounds than the formula suggests.
One study in the Journal of the American Medical Association showed just how much Americans are overeating. A mathematical model revealed that, over 28 years, a typical man increased his caloric intake by 680 calories a day, putting him into the obese category.
The research does say small changes only make small differences in obesity, but they're useful if they lead to bigger changes. Studies have shown the most successful weight loss patients eat a low calorie, low-fat diet, have high levels of physical activity -- one report just last week said an hour a day, eat breakfast and maintain a consistent eating pattern on weekdays and weekends.
New Weight Loss Math Makes Task More Daunting