Science & Technology

/

Knowledge

Why diets backfire: A year or more after weight loss, the desire to eat grows stronger

Melissa Healy, Los Angeles Times on

Published in Science & Technology News

Every six months from enrollment to two years out, researchers checked in to conduct a series of tests. Before and for three hours after meals, they gauged subjects' subjective feelings of hunger, fullness and desire to eat, and asked how much food they planned to consume. And they measured circulating levels of five separate hormones that regulate appetite to see how they responded to the prospect of a meal or a meal just eaten.

What they found was the body's reaction to weight loss shifted over time.

In the short run -- four weeks after their exercise-and-weight-loss regimens got underway -- the subjects had lost an average of 3.5 percent of their body weight. Their levels of appetite-boosting hormones had risen rapidly -- probably a response to their getting roughly 31/2 hours of exercise per day while at the retreat.

But they did not report increased hunger or desire to eat. And with rising levels of satiety hormones, they were feeling more full in the wake of eating a meal.

As they met their weight-loss goals, however, things changed.

At the end of a year of dieting and exercise, the study's participants had lost about 7.4 percent of their weight and had improved their fitness considerably. But they reported to researchers a significant increase in their hunger and desire to eat. And the sensations of fullness they reported after meals had plummeted.

Two years after enrolling in the study -- and a year into their weight-maintenance programs -- the subjects had, on average, kept the weight from coming back. But they continued to report levels of hunger and desire to eat that were just as high or higher than at the end of Year One. And they reported feeling no more full after a meal.

At both time points, their hormone levels continued to show increases in appetite-stimulating compounds, as well as those that would signal fullness. Though they lost the weight and -- with the study's unusual level of support -- managed to keep it off, they were hearing the loud cries of their hunger-boosting hormones. The fullness ones, not so much.

--Sponsored Video--

The good news, according the researchers: A sustained and supportive program of dietary restriction and physical activity does induce weight loss and can help very obese patients keep the weight off.

The bad news: "Patients with severe obesity who have lost significant amounts of weight ... will have to deal with increased hunger in the long-term."

If these patients are to beat the odds and sustain their weight loss, professionals working with them will have to find ways to help them cope with that, they added.

(c)2018 Los Angeles Times

Visit the Los Angeles Times at www.latimes.com

Distributed by Tribune Content Agency, LLC.

 

Comments

blog comments powered by Disqus