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Weight Loss New Formula: A Study
– Reported, July 09, 2012
Until recently, the standard weightloss axiom centred around the notion that a pound of body fat contains 3,500 calories’ worth of energy. So by increasing your activity or cutting your intake by, say, 500 calories per day, you could expect to lose a pound of body fat per week
Unfortunately, while the 3,500-calorie rule – also known as the static model of body weight change – is wonderful for its simplicity, it is also inherently flawed.
Perhaps the most glaring flaw with the static model is that, even if we did lose pounds at a predictable rate, your weight eventually levels off.
Until recently, the 3,500 calorie rule was all that we had to predict weight loss. Last year, however, a group of researchers led by Dr. Kevin Hall of the National Institute of Diabetes and Digestive and Kidney Diseases, introduced a new model that predicts weight loss by accounting for the way our metabolism, or the amount of energy our body burns at rest, changes as we lose weight.
Happily, the revised model gives a much more accurate prediction of weight changes as a result of cutting down intake than the old one. Unfortunately, it also demonstrates that weight loss is a much slower process than the 3,500-calorie rule suggested.
Roughly speaking, the dynamic model predicts that for every 10 calories you permanently add or subtract from your diet, you can expect a life-long weight change of about one pound. Timingwise, about half of that weight loss would occur in the first year, and about 95 per cent would be achieved within three years. So putting it another way, if you want to lose 10 pounds, you would need to permanently reduce your intake by about 100 calories per day; after a year, you could expect to be down about five pounds, and after three years, you would be within a half-pound of your goal.
As an extension of the dynamic model, Hall and colleagues have developed an online tool known as the Body Weight Simulator (bwsimulator.niddk.nih.gov), which allows users to estimate their individual predicted long-term weight changes (note that the simulator allows users to add as much information as they have available; the basic model requires basic variables such as height, weight and age, but advanced options allow for other variables such as body fat to be entered).
While permanent weight loss remains a tremendous challenge, having a more accurate tool such as this can give a better idea of what to expect in the long run. Also, while this dynamic model predicts slower weight loss than the older, 3,500 calorie model, it also illustrates the importance of even the tiniest changes to our habits.
Credits: The Province.
Read more: http://www.theprovince.com/