Our lives are full of weight-loss “advice.” Television infomercials are constantly pitching new diets and new exercise videos. Grocery store checkout lines are full of magazines selling “these 10 simple weight-loss tricks.” And if you really want to be inundated, walk through one of the ubiquitous “nutrition” stores at your local mall. You’ll find so many supplements that can supposedly trim the appetite or speed up your metabolism that you’ll be left wondering—when did the word nutrition stop meaning food, and starting meaning pills and powders?
In the world of weight-loss claims, it is hard to separate fact from fiction. Fortunately, the science of achieving a healthy weight is starting to catch up with the hype.
The Science of Weight Loss
During the past 20 years, weight loss has become a well-respected field of scientific inquiry. Clinical trials are no longer used just to test new medicines. We now have high-quality evidence that allows us to support or refute some our most firmly held weight-loss beliefs.
A recent article in the New England Journal of Medicine should be required reading for doctors and patients alike. Doctors from the University of Alabama at Birmingham set out to summarize what we know, and what we don’t know, about weight loss. They divided our common beliefs into three categories: myths, presumptions, and facts.
A few of the weight-loss myths they cataloged might surprise you.
Myth: Small decreases in calorie intake produce large, sustainable losses of weight. This simply isn’t true. Our body’s energy expenditure goes down when we eat less, so small changes inevitably produce small and diminishing returns. Diets work—but to a scientist, a “diet” means a drastic overhaul of your eating habits.
Myth: You should set small weight-loss goals. While it might have seemed obvious that people are more strongly motivated by goals that they can more easily attain, science refutes this. Ambitious goals—think “The Biggest Loser” here—produce the best results.
Myth: Gradual weight loss is better. Most people think that gradual weight loss is healthier; however, this just does not appear to be true. Rapid weight loss is safe and is just as sustainable as gradual weight loss.
Myth: You have to wait until you are “ready” to lose weight. Perceived readiness in a participant does not predict weight-loss success in clinical studies. Anybody in a weight-loss program can lose weight at any time. Studies in fact show that the right time for weight loss is right now.
Think big, think now!
As a doctor, I am often guilty of thinking small. That is, I ask my patients to make small changes in their eating habits, to lose just a few pounds, and to gradually adapt healthier behaviors. I too often assume the “snowball effect”—that just a little initial weight loss will get the ball rolling. And I commonly allow my patients to make excuses for deferring enrollment in exercise or diet programs, and so will make a note to refer them at our next visit.
It turns out that, on the contrary, we should think big and think now! To lose weight, we must be ready to make big changes in what we eat. By definition, a diet is not a small change in eating habits; it is in fact a big change! So think about setting some ambitious goals for yourself. It’s probably OK to lose a lot of weight quickly. And perhaps most importantly, don’t think you can outsmart yourself about the best time for losing weight. Everybody can be ready for weight loss. The time is probably now.