Calorie restriction causes temporal changes in liver metabolism
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 diet 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 calorie restriction and subsequent weight loss," 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 magnetic resonance spectroscopy were used to determine insulin 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 insulin sensitivity 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.
- Low-carb diets alter glucose formation by the liverMon, 20 Oct 2008, 14:35:30 EDT
- Low-carbohydrate diet burns more excess liver fat than low-calorie diet, UT Southwestern study findsTue, 20 Jan 2009, 5:49:35 EST
- Moderately reduced carbohydrate diet keeps people feeling full longerThu, 11 Jun 2009, 14:12:47 EDT
- Diets that reduce calories lead to weight loss, regardless of carbohydrate, protein or fat contentWed, 25 Feb 2009, 17:22:19 EST
- Researchers note differences between people and animals on calorie restrictionWed, 24 Sep 2008, 15:42:51 EDT
- Calorie restriction causes temporal changes in liver metabolismfrom Science CentricTue, 5 May 2009, 14:07:21 EDT
- Calorie restriction causes temporal changes in liver metabolismfrom PhysorgMon, 4 May 2009, 17:14:15 EDT
- Calorie restriction causes temporal changes in liver metabolismfrom Science BlogMon, 4 May 2009, 16:49:31 EDT
Latest Science NewsletterGet the latest and most popular science news articles of the week in your Inbox! It's free!
Learn more about
Check out our next project, Biology.Net
From other science news sites
Popular science news articles
- UC Davis engineers create on-wetting fabric drains sweat
- Not just blowing in the wind: Compressing air for renewable energy storage
- Amazon River exhales virtually all carbon taken up by rain forest
- 1 in 10 teens using 'study drugs,' but parents aren't paying attention
- Slow earthquakes: It's all in the rock mechanics
No popular news yet
No popular news yet
- Stem cell transplant restores memory, learning in mice
- 2 landmark studies report on success of using image-guided brachytherapy to treat cervical cancer
- Researchers discover mushrooms can provide as much vitamin D as supplements
- Cutting back on sleep harms blood vessel function and breathing control
- Study: Low-dose aspirin stymies proliferation of 2 breast cancer lines