If you’re considering going on a diet to lose weight, beware—research shows that for many people the net effect of diets is weight gain.
This is not to say that diets don’t work—they do. Most people who go on a diet lose weight, usually through some combination of eating less and eating differently.
But the weight comes back—sometimes all of it, and then some. That’s what research studies have found for a large percentage of dieters. What accounts for this difficulty keeping the weight off?
I recently interviewed two psychologists who specialize in behavioral change and sustained weight loss: Dr. Aria Campbell-Danesh and Dr. Lucy Faulconbridge (both coincidentally from the UK).
I learned a lot during our discussions, especially about why the weight we lose through dieting tends to come back. The following factors stood out to me:
Dieting Demands Deprivation
All diets are based on what not to eat, whether carbs, fat, refined sugar, other food types, or simply quantity. Placing these limits on our eating may not feel too restrictive at first; in fact, we might enjoy the novelty.
But over time we start to feel like we’re missing out. “If only I could eat that,” we think as we watch those around us eat our “forbidden” foods. Will power is a finite resource, and eventually we’re going to cave in. We may even end up binging on the foods we’ve been missing.
When we feel like we’re not allowed to have things, our minds tend to fixate on them. Thus our motivation to deprive ourselves is going to erode over time.
Diets Are Temporary
If I’m “on a diet,” that strongly implies that at some point in the future I’ll be off the diet. Indeed, many diet programs are specifically designed to be a fixed length, like “The 17 Day Diet,” “The 22 Day Revolution,” the 30 days of Whole30, and countless others.
Given that diets emphasize deprivation, inevitably we’ll return to our old ways of eating once the diet ends. We may even “make up for lost time” and binge on the foods we’ve avoided—which is even more problematic for the following reason.
Dieting Lowers Metabolism
Aria pointed out that some of the weight lost by dieting will be muscle, and that drop in lean mass slows down our metabolism. Our bodies also become more efficient at extracting energy from our food, which also slows metabolism—an effect that may be especially pronounced among people who have been obese, as Lucy noted.
This drop in metabolic rate makes it hard to maintain weight loss, which means we’ll have to be extra motivated to avoid gaining back the weight.
Maintenance Isn’t Very Motivating
It’s exciting when we see progress as we shed pounds, and that sense of progress feeds our motivation to stick with the changes we’ve made. The people around us can fuel our motivation, too, as they compliment us on losing weight.
But if we reach our target, where does our sense of progress come from? Our motivational system is tuned to relative changes, so it’s hard to be inspired by the status quo. Thus our motivation is typically lower for maintaining gains versus making progress.
What’s the Alternative?
Thankfully my interviewees didn’t stop with describing the obstacles to sustained weight loss—they both offered evidence-based strategies that are much more likely to work
Some have too much to eat – some have nothing to eat.