Calorie restriction causes temporal changes in liver metabolism

May 04, 2009

Moderate calorie restriction causes temporal changes in the liver and skeletal muscle metabolism, whereas moderate weight loss affects muscle, according to a new study in Gastroenterology, the official journal of the American Gastroenterological Association (AGA) Institute. In addition, researchers found that short-term calorie restriction (CR) with a low-carbohydrate diet caused a greater change in liver fat content and metabolic function than short-term CR with a high-carbohydrate diet.

Insulin resistance is the most common metabolic complication associated with obesity and is associated with an increased risk of developing non-alcoholic fatty liver disease (NAFLD) and type 2 diabetes. Although an energy-deficit is the cornerstone of therapy for obesity, the most appropriate macronutrient composition of diet therapy needed to improve metabolic health remains controversial.

"Our data underscore the complexity of the metabolic effects of calorie restricition with diets that differ in macronutrient composition, and demonstrate differences among organ systems in the response to and subsequent ," said Samuel Klein, MD, of the Washington University School of Medicine and lead author of the study. "Our findings help explain the rapid improvement in glucose levels observed after low-calorie diet therapy and bariatric surgery," he added.

In the present study, 22 obese patients were randomized to a high-carbohydrate or low-carbohydrate energy-deficit diet. A euglycemic-hyperinsulinemic clamp, muscle biopsies and were used to determine action, cellular insulin signaling and intrahepatic triglyceride (IHTG) content before, after 48 hours and after ~11 wks (7 percent weight loss) of diet therapy. An euglycemic-hyperinsulinemic clamp is a widely used experimental procedure for the determination of insulin sensitivity.

Researchers found that short-term CR caused a rapid decrease in IHTG content, an increase in hepatic insulin sensitivity and a decrease in endogenous glucose production rate, whereas longer-term CR and a moderate 7 percent weight loss improved skeletal muscle in conjunction with an increase in cellular insulin signaling. The effect of moderate CR in obese patients with either a low-fat or low-carbohydrate diet on metabolic function is a continuum, with differential effects on specific organ systems.

Source: American Gastroenterological Association (news : web)

Explore further: Regulating the regulators: Degradation is key to the activity of the miR-21 oncomiR

add to favorites email to friend print save as pdf

Related Stories

Low-carb diets alter glucose formation by the liver

Oct 20, 2008

A new study shows that a low-carbohydrate diet changes hepatic energy metabolism. When carbohydrates are restricted, the liver relies more on substances like lactate and amino acids to form glucose, instead of glycerol. These ...

Low-carb diets can affect dieters' cognition skills

Dec 11, 2008

A new study from the psychology department at Tufts University shows that when dieters eliminate carbohydrates from their meals, they performed more poorly on memory-based tasks than when they reduce calories, but maintain ...

Recommended for you

Autophagy protects insulin-secreting cells of the pancreas

Jul 19, 2014

Diabetes affects almost 400 million people worldwide. One of the hallmarks of this disease is a loss of pancreatic β cells, which secrete insulin. In many patients the reduction of β cells is associated an accumulation ...

User comments : 0