THURSDAY, Oct. 11, 2012 (HealthDay News) -- For overweight people with diabetes, intensive exercise and dieting not only aids weight loss, it can also help train their fat cells to produce a hormone believed to boost production of "good" cholesterol, according to a new study.
And this so-called "good" cholesterol, or HDL cholesterol, has been linked to positive effects for cardiovascular health.
The new study, from researchers at The Methodist Hospital in Houston, included data on overweight and obese people with type 2 diabetes who were taking part in a multicenter clinical trial examining how increased physical activity and reduced calorie intake affected their risk for cardiovascular disease.
The participants were randomly assigned to either an intensive diet and exercise program (the "lifestyle intervention" group) or a program that offered only diabetes support and education and no lifestyle changes (the "control" group).
After one year, the lifestyle intervention group had achieved significant improvements in a measure of total fat called "adiposity," fitness, blood sugar levels and fat levels, the investigators found.
In addition, while levels of "bad" LDL cholesterol did not change, levels of the fat hormone adiponectin and HDL cholesterol did increase: Total adiponectin produced by fat cells increased about 12 percent and HDL cholesterol increased nearly 10 percent in the people who made lifestyle changes, compared to those in the control group, the research showed.
It's well established that adiponectin plays a role in fat burning and sugar storage. This study suggests that the hormone also encourages the liver to produce HDL cholesterol, the study authors pointed out in a hospital news release.
"What we're learning is that even overweight people who are physically active and eating a healthy diet are getting benefits from the lifestyle change," principal investigator Dr. Christie Ballantyne, director of the Center for Cardiovascular Disease Prevention, part of the Methodist DeBakey Heart and Vascular Center at The Methodist Hospital in Houston, said in the news release.
"When you exercise and diet, you're improving the function of your adipose tissue, your heart and vascular systems, and even muscle performance. You're getting a lot of benefits that you may not see by just looking at the weight on a scale," he added.
The study was released online in advance of publication in an upcoming print issue of the Journal of Lipid Research.
The American Heart Association has more about cholesterol.