Weight Regain may not be Solely a Willpower Issue
Some people may actually be programmed to gain weight back based on their levels of two key appetite hormones, leptin and ghrelin, according to study author Ana Crujeiras, Ph.D., of Compejo Hospitalario Universitario de Santiago in Spain
Appetite Willpower Study
In the new study, 104 obese or overweight men and women ate a low-calorie diet for eight weeks and were followed up with six months later. Their body weight, ghrelin, leptin, and insulin levels were measured before, during, and after the diet.
Ghrelin is the "go" hormone that tells you when to eat, and leptin is the "stop" hormone that tells you when to stop eating.
On average, study participants dropped about 5% of their body weight while adhering to the low-calorie diet. Six months later, 53% of the participants maintained their weight loss, while 53% regained 10% or more of the weight they had lost. Those individuals with higher leptin and lower ghrelin levels before dieting were more prone to regain weight according to the study.
Results Seem Counter-Intuitive
While this may seem counter-intuitive based on the actions of these hormones, the researchers suggest that it may be a matter of some people being resistant to the effects of the two key appetite hormones, leptin and ghrelin.
Their brains may not be getting the satiety (fullness) messages that these two key appetite hormones are delivering. You may have a lot of leptin, but your brain is resistant to its effects; much like people with type 2 diabetes become resistant to the effects of the hormone insulin.
The new research likely applies to significant numbers of people who are finding the battle of the bulge to be an uphill one.
Going forward, "these hormone levels could be proposed as biomarkers for predicting obesity-treatment outcomes," the researchers conclude. "Our findings may provide endocrinology and nutrition professionals a tool to identify individuals in need of specialized weight-loss programs that first target appetite hormone levels before beginning conventional dietary treatment."
The research may also help drive the research pipeline to look at drugs aimed to combat or improve leptin resistance.
The research appears in an online version of the Journal of Clinical Endocrinology & Metabolism.