Why the weight lost comes back

October 28th, 2011 by MorganDowney Leave a reply »

It comes as no surprise that regaining weight after weight loss is common and frustrating to dieters. It also limits choices for policy makers who, in general, had avoided treatment strategies because of the transient nature of weight loss.

It also comes as no surprise that, after weight loss, metabolism of overweight persons slowed down and hormonal changes increased the powerful sensation of hunger. This double whammy makes maintenance of weight loss so challenging.

Now come researchers from Australia who studies a small group (only 50 overweight and obese patients without diabetes) . The group lost about 13.5kg  which led to reductions in levels of leptin, peptide YY, cholesystokinin, insulin and amylin and increases in ghrelin. There was also an increase in subjective appetite.(See Brain and Gut for background.) What is new is that these changes persisted for one year after initial weight loss. They did not revert to the levels recorded before weight loss, probably explaining why so many dieters relapse. See http://www.ncbi.nlm.nih.gov/pubmed/22029981.

Gina Kolata, writing in the New York Times, quotes Dr. Jules Hirsch as saying that researchers may just not know enough about obesity to prescribe solutions yet. “One thing is clear, he said, “A vast effort to persuade the public to change its habits just hasn’t prevented or cured obesity.” “We need more knowledge,” Dr. Hirsch said, “Condemning the public for their uncontrollable hedonism and the food industry for its inequities just doesn’t seem to be turning the tide.” Study Shows Why It’s Hard to Keep Weight Off – NYTimes.com