Food and Nutrition Health — 01 January 2013

DietingBy Richard Lenti

With the holidays behind us, many Americans are looking down at their waistlines, hoping to shed some of the extra weight they managed to put on. But how they gained that weight and where the fat went could be the difference between success and failure.

According to a study published in the Journal of the American Medical Association (JAMA), people who ate foods that contained a high level of fructose will have a harder time losing weight than those who consumed glucose. They are also less likely to control their appetite.

While both are sugars, fructose is found in fruits and processed corn syrup. Glucose is generally produced in the body after eating carbohydrates.

Researchers led by Dr. Kathleen A. Page at Yale University School of Medicine studied 20 healthy adult volunteers who had magnetic resonance images (MRI) of their brains after ingesting a fructose or glucose drink.

What the MRI’s detected were changes in the brain’s blood flow caused by glucose and fructose.

Glucose significantly reduced cerebral blood flow and activity in parts of the brain that regulate appetite — providing an increased feeling of satisfaction and fullness.

Fructose had pretty much the opposite effect — making people want to eat more.

“Glucose but not fructose ingestion reduced the activation of the hypothalamus, insula, and striatum—brain regions that regulate appetite, motivation, and reward processing,” Page wrote.

This new study adds to an increasing body of research showing how the body processes the two sugars.  One documented difference is that glucose enters the body through the bloodstream, while fructose is processed by the liver. If too much fructose enters the liver, it’s converted into triglycerides which are a risk factor for heart disease.

Researchers have also found that the weight gained from fructose is stored in the belly, while most of the fat gained from glucose is subcutaneous, stored under the skin.  Belly fat has been linked to an increased risk for heart disease and diabetes.

Previous research has also shown that a rise in fructose consumption has paralleled the increasing prevalence of obesity, and high-fructose diets are thought to promote weight gain and insulin resistance. Page cites lab tests with rodents where the administration of glucose promoted satiety in the animals while those administered fructose wanted to eat more.

In an accompanying editorial, also appearing in JAMA, two doctors at Oregon Health & Science University wrote that the study provides further evidence that fructose can cause an unhealthy increase in food consumption.

“Advances in food processing and economic forces leading to increased intake of added sugar and accompanying fructose in U.S. society are indeed extending the supersizing concept to the population’s collective waistlines,” wrote Jonathan Purnell, MD, and Damien Fair, PhD.


About Author

Richard Lenti

Richard Lenti has worked as a news writer for the last 20 years at various television stations in Los Angeles. He is a Golden Mike winner and a graduate of California State University, Fresno. With roots in print journalism, Richard is excited to be “published” once again; having people read his work as opposed to having it read to them. As a freelance writer his work has appeared in the Easy Reader, L.A. Jazz Scene, Irrigation and Green Industry, and the KCAL 9 Online website.

(1) Reader Comment

  1. This article explains the medical research very well–also helps me see what we need to change in our diets at home. I’ve been trying to lose weight for years and struggling–the belly fat is getting worse. My husband already has Type II Diabetes and high cholesterol. Making this change is worth a shot!