Lose weight. Regain it. Blame hormones?

U. MELBOURNE (AUS) — Obese people may regain weight after dieting due to hormonal changes, a new study shows.

Worldwide, there are more than 1.5 billion overweight adults, including 400 million who are obese. In Australia, it is estimated more than 50 percent of women and 60 percent of men are either overweight or obese.

Although restriction of diet often results in initial weight loss, more than 80 percent of obese dieters fail to maintain their reduced weight.

Published in the New England Journal of Medicine, the study involved 50 overweight or obese adults, with a BMI of between 27 and 40, and an average weight of 95 kg (209 pounds), who enrolled in a 10-week weight loss program using a very low energy diet.  A kilogram is equal to 2.2 pounds.

Levels of appetite-regulating hormones were measured at baseline, at the end of the program, and one year after initial weight loss.

The results showed that following an initial weight loss of about 13 kgs, the levels of hormones that influence hunger changed in a way that would be expected to increase appetite. These changes were sustained for at least one year. Participants regained around 5kgs during the one-year period of study.

The study shows the important roles that hormones play in regulating body weight, making dietary and behavioral change less likely to work in the long-term, says Joseph Proietto, professor from the University of Melbourne and Austin Health.

“Our study has provided clues as to why obese people who have lost weight often relapse. The relapse has a strong physiological basis and is not simply the result of the voluntary resumption of old habits.”

Although health promotion campaigns recommended obese people adopt lifestyle changes such as being more active, they are unlikely to lead to reversal of the obesity epidemic.

“Ultimately it would be more effective to focus public health efforts in preventing children from becoming obese. The study also suggested that hunger following weight loss needs to be addressed. This may be possible with long-term pharmacotherapy or hormone manipulation but these options need to be investigated,” he says.

The study was done in collaboration with La Trobe University.

More news from the University of Melbourne:

chat9 Comments


  1. Rachel Styles

    Most people think they can just starve themselves to lose weight but you can’t do that because your body will go into something called starvation mode. What happens is your body will slowly eat itself. If you want to know why you can’t starve yourself to lose weight, this article gives a great explanation on it.

  2. HowToLoseWeight

    Important questions left un-answered:

    1. What evolutionary purpose would such hormone problems serve?

    2. Is there a point at which these levels drop, or are people doomed to be hungry/fat forever?

    Fascinating study though.

  3. Suzan

    Hormones effect women big time when it comes to gaining weight!. Pregnancy and becoming a mom comes at a price! women tend to gain weight 10- 40 pounds. I gained 15 pounds and kept on adding more and more. I found this site: It helped me pick a weight loss program and I have lost 10 pounds in 3 months. slowly but surely.

  4. Mikestonn

    The environmental factors involved with diabetes and obesity have largely been ignored by the media. A blame the victim mentality has been created by those who are not knowledge about chemical pollutants. The “Super size me” lets blame McDonald’s and other private food enterprises shift the blame from the governments that allow chemical pollutants in the environment. Many cannot lose weight which was reported on Philadelphia news The link to pollutants as a cause of diabetes
    In a recent study from Ohio States University researchers exposed young mice to higher levels of air pollution and saw surprising results. Dr. Rajagopalan says, “What we found was, when you expose animals very early on in life, over a duration of 6 to 8 weeks, they do develop very subtle abnormalities in metabolic dysfunction

  5. Galina Oneill

    Wonderful guide and guidelines. Looking forward to lose a few kilos. I’ll provide some feedback immediately after i try this. Appreciation!


    Weight loss, in the context of medicine, health or physical fitness, is a reduction of the total body mass, due to a mean loss of fluid, body fat or adipose tissue and or lean mass, namely bone mineral deposits, muscle, tendon and other connective tissue. Thanks.


    naturally like your website but you have to check the spelling on quite a few of your posts. A number of them are rife with spelling problems and I find it very troublesome to tell the truth however I will definitely come again again.

  8. natural green coffee bean

    Hi, yup this paragraph is genuinely pleasant and I have
    learned lot of things from it on the topic of blogging.

  9. Lean Muscle FOrmula Price

    My brother suggested I might like this website. He was totally right.
    This post truly made my day. You cann’t imagine just how much time I had spent for this information! Thanks!

We respect your privacy.