Low-carb diets alter glucose formation by...( A new study shows that a low-carbohy...),Health

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 findings are in the November issue of Hepatology, a journal published by John Wiley & Sons on behalf of the American Association for the Study of Liver Diseases (AASLD). The article is also available online at Wiley Interscience (www.interscience.wiley.com).

Over the past 30 years, the U.S. population has reduced its fat intake, and increased its consumption of carbohydrates. During the same time period, obesity has been rising along with the prevalence of metabolic liver disease in which fatty deposits in the liver can lead to inflammation, fibrosis and cirrhosis. Some evidence has suggested that a high carbohydrate diet leads to fat formation in the liver, although confirming the association has been difficult.

To better understand hepatic energy production and glucose formation among various types of diets, researchers led by Jeffery Browning of the University of Texas Southwestern Medical Center measured the sources of hepatic glucose and TCA cycle flux in weight-stable subjects, and in subjects following carbohydrate- or calorie-restricted diets.

They recruited 14 subjects whose BMI fell between 25 and 35, and divided them into two groups of seven, matching them for age, BMI, gender and ethnicity. They also included seven lean subjects (BMI < 25) to act as a weight-stable comparison group.

The high-BMI groups followed either a low-carbohydrate or a low-calorie diet for fourteen days, while the weight-stable group continued their regular diet. All subjects then underwent an overnight metabolic study in which the researchers simultaneously assessed the metabolic pathways of hepatic glucose production and the TCA cycle.

In the weight-
'/>"/>