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Preventive care
Obesity: less risky for some people
E-mail| Print | Comments () July 5, 2011 12:25 PM

By Deborah Kotz, Globe Staff

No question being overweight or downright obese raises health risks, but just how much those extra pounds harm our health has long been a matter of debate. New research indicates that some 30 percent of obese individuals may be just as healthy as slim people -- at least when it comes to their arteries.

That’s according to a study published yesterday in the Journal of the American College of Cardiology in which researchers from Boston University School of Medicine and Boston Medical Center took biopsies of fat tissue from 109 obese volunteers and 17 lean ones. They found that about 70 percent of the obese participants -- who had an average body mass index of 45, which translates to a weight of 263 pounds for a 5’4” person -- had high levels of inflammation in their fat tissue, accompanied by increased cholesterol levels, blood pressure, insulin, and triglycerides. They also had abnormal blood vessel function diagnosed via ultrasound imaging.

Those who weren’t overweight -- with an average BMI of 22, or 128 pounds for a 5’4” person -- had higher “good” HDL cholesterol levels and no signs of diabetes, high blood pressure, or abnormal blood vessel function. They also had no signs of inflammation in their fat tissue. No surprises there.

What’s interesting, though, is that some 30 percent of those in the obese group -- probably due to genetic reasons -- also didn’t have body fat with high levels of inflammation and had arteries that looked like those of their thin counterparts. (This obese group’s levels of insulin, triglyercides, and hypertension were in between the levels of the thin group and the high-inflammation obese group.)

“I think it’s well recognized that a number of individuals despite being extremely obese have good blood tests and good cardiovascular function,” says study co-author Dr. Noyan Gokce, a cardiologist at Boston Medical Center. “And our findings suggest it could be due to reduced inflammation.”

Inflammatory chemicals called cytokines, he adds, could spill out of fat tissue and into the circulating blood, damaging blood vessels throughout the body and causing artery plaque to form.

This finding, of course, begs the question: Perhaps some overweight folks don’t need to worry so much about losing those excess pounds? Can’t they just get a few blood tests and an ultrasound to see whether they’ve got increased health risks?

Unfortunately not, says Gokce. “To say that low levels of fat inflammation protects you against all health consequences of obesity would be a stretch -- since there are other health risks associated with obesity like cancer.”

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