Study unveils gut health and obesity link, suggests novel approaches to weight management

26 Jun 2019 --- Loss of body fat causes the growth of the intestine and increases its capacity to absorb nutrients, which may present an opportunity for a new approach to weight management. This is according to research from Teagasc, the semi-state authority in the Republic of Ireland responsible for R&D services in the agri-food sector and researchers from the University of Aberdeen, Scotland. The researchers found that the depletion of fat stores inside the body causes the growth of the intestine via a signaling mechanism involving the brain (fat-brain-intestine signaling). The researchers note that the findings may lead to novel weight loss intervention methods.

“This effect is not limited to calorie restriction as our findings suggest that other interventions (specifically bariatric surgery, lactation, cold exposure and dietary whey protein intake), all of which decrease body fat, cause the above change in the intestine,” Kanishka Nilaweera, Research Officer for Food Biosciences Research Department at Teagasc Food Research Centre, tells NutritionInsight.

“While most nutritional interventions, such as calorie restriction, cause the loss of body fat, the weight is generally regained when one stops these interventions. This is generally the case post-weight loss because most people find it hard to continue with weight loss interventions long term,” he adds.

Obesity has become a global epidemic, affecting over 600 million adults worldwide and is linked to the over-consumption of high-energy palatable foods. While dieting is a popular way to lose body fat, it may cause the intestine to grow. The resulting increased nutrient absorptive capacity of the intestine may, in turn, cause quicker weight gain post dieting, the researchers say.

 Kanishka Nilaweera, Research Officer at the Teagasc Food Research Centre“This work will pave the way for more sustainable weight loss interventions”, explains Nilaweera. “Along with the obesity epidemic, there is an under-nutrition epidemic which affects over 462 million people worldwide. This is due to either physical inability to consume food (due to old age or chronic illness) or psychological reasons (anorexia).”

“For the affected individuals, strategies have to be developed to better absorb the nutrients that they are currently getting. This can potentially be done by targeting fat-brain-intestinal signaling components sensitive to nutrients with the objective of stimulating the growth of the intestine,” he adds.

In the study, the researchers looked into the use of whey proteins to address this problem as these proteins cause the gut to shrink.

“Our research shows that whey protein intake can suppress the growth of the intestine. We focused on these proteins because they are part of our diet since birth (in milk), but here we have isolated these milk proteins and enriched them in a diet. By feeding it to mice, we showed that the whey proteins suppress the growth of the intestine,” Nilaweera says. 

According to Nilaweera, following the cessation of the weight loss-intervention, one must be careful of the diet one chooses, because the extra calories ingested can quickly lead to a substantial weight regain due to the above-mentioned change in the intestine. Therefore, maintaining a low-calorie diet post-weight loss intervention would help to minimize weight regain.

Going forward, the researchers are planning more research to discover how dietary whey proteins cause the gut to shrink. 

“We believe that digestion of these proteins in the gut produces some mixture of peptides and/or amino acids, which then affects the intestine. Ultimately, we want to find these active components in whey proteins and include these in human diets, so that these active components can produce the same effect on the intestine (and hence body fat) within a few meals as compared to daily consuming whey proteins,” Nilaweera concludes.

By Kristiana Lalou