In case you missed the torrent of social media commentary on the drastic weight loss of this year’s Biggest Loser winner, here’s the gist: Losing 155 pounds is a big deal. It gets people talking. It causes a stir. That amount of weight loss, however, may have some less than desirable consequences. Our bodies are programmed to defend against starvation, so substantial amounts of weight loss often get some physiological alarm bells ringing.
When individuals set out to maintain a weight lower than their previous highest weight (a concept known as “weight suppression”), they find themselves up against a number of biologically determined roadblocks. Diet-induced weight loss activates behavioral, hormonal, and metabolic responses that are adaptive in situations where starvation is due to a lack of available food, but can actually lead to weight gain when food is available. In other words, weight loss – particularly extreme weight loss – signals to the body that it should take in and hold onto as many calories as possible, because food might be difficult to come by. Great when you’re on a deserted island, less helpful when you’re walking past Starbucks and McDonald’s every day on your way to work.
With all these biological gizmos and gadgets churning away inside slimmed down bodies, sending not-so-subtle messages to eat more food more frequently, it comes as no surprise that weight suppression has been linked with increases in overeating and the onset of eating disorder symptoms. Among individuals with full-syndrome bulimia nervosa, higher levels of weight suppression have been associated with more frequent binge eating and longer time to meaningful symptom improvement when in treatment. Similarly, in a study of inpatients with anorexia nervosa, those who reported binge eating and purging while in the hospital tended to have been at higher weights prior to the onset of their illness.
We still don’t know much about the biological and behavioral consequences of long-term weight suppression in individuals with eating disorders. What we do know has led us to wonder about whether or not eating disorder patients with high levels of weight suppression might benefit from slightly different (or very different) treatment approaches than others with these illnesses.
With all of our questions, we are on a mission to get some answers. In collaboration with the Lowe Lab at Drexel University, we here at Columbia are currently conducting a study to test out our best guesses about how dieting, weight suppression, metabolism, and appetite interact in bulimia nervosa. We’re hitting all the highlights: hormone levels, resting metabolic rate, body composition, and bone density are all tested and compared between individuals with high and low levels of weight suppression. To look in detail at the impact of weight suppression on eating and appetite, study participants carry smartphones that are programmed to ask them questions a few times each day. This cutting-edge method of data collection, known as Ecological Momentary Assessment (EMA), gives us a glimpse into what goes on for folks as they go about their everyday real lives.
If you or someone you know struggles with bulimia nervosa and would like to learn more about participating in our weight suppression study and receiving treatment, contact our program. Advancing science and getting specialized care for bulimia nervosa? That should get people talking.
