AUG 19, 2016

"Healthy Obesity" May be a Myth

WRITTEN BY: Julianne Chiaet
Back in December, I wrote an article titled "Being 'Lean and Unfit' is Better Than Being 'Fat and Fit’" that outlined research suggesting normal weight men, regardless of their fitness level, were at a lower risk of death than obese individuals in the highest quarter of aerobic fitness. The article ended up being the most popular one I’ve written for this publication - and this popularity was partly due to the fact that the research was both highly disconcerting and directly affected many individuals (specifically, individuals on Reddit). 
 

In general, those considered metabolically fit have a high sensitivity to the hormone insulin. Until recently, medical experts estimated that up to 30 percent of obese individuals were metabolically healthy; and these individuals were less prone to obesity-related complications. 

Obesity-related complications include cancer, heart disease, and stroke. Symptoms of these diseases don’t always lie in areas where extra fat has accumulated. Yet, obesity increases the risk of those diseases because it is a condition of systemic inflammation, according to research from the Institute for Molecular Medicine.

Now, research published on August 18 in Cell Reports has provided further evidence that being healthy while obese is a myth.

Researchers found that white tissue samples from obese patients showed nearly identical abnormal changes in gene expression in response to insulin regardless of whether the patient was metabolically healthy or unhealthy.
 
"The findings suggest that vigorous health interventions may be necessary for all obese individuals, even those previously considered to be metabolically healthy,” said Mikael Rydén, first author of the paper, from the Karolinska Institutet. "Since obesity is the major driver altering gene expression in fat tissue, we should continue to focus on preventing obesity."

The researchers are currently tracking the participants post-bariatric surgery to see whether the weight loss normalizes gene expression in response to insulin stimulation. 

Source: Cell Press press release via EurekAlert!, Cell Reports, Rydén et al.: "The Adipose Transcriptional Response to Insulin Is Determined by Obesity, Not Insulin Sensitivity"