Fat in obese 'sick' compared to lean fat

PHILADELPHIA, Aug. 28 (UPI) -- Researchers at Temple University in Philadelphia said that fat in obese patients is "sick" when compared to fat in lean patients.

Lead author Dr. Guenther Boden theorizes that "sick fat" could more fully explain the link between obesity and higher risk of diabetes, heart disease and stroke.

Researchers from the departments of endocrinology, biochemistry and surgery at the Temple University School of Medicine took fat biopsies from the upper thighs of six lean and six obese patients and found significant differences at the cellular level.

"The fat cells we found in our obese patients were deficient in several areas," Boden said in a statement. "They showed significant stress on the endoplasmic reticulum and the tissue itself was more inflamed than in our lean patients."

Endoplasmic reticulum is found in every cell and helps synthesize proteins and monitor how they're folded, but the stress that Boden describes causes the endoplasmic reticulum in fat cells to produce several proteins that ultimately lead to insulin resistance, which has been linked to obesity-related conditions.

The study, published in the September issue of Diabetes, said reducing weight can help reduce stress on the endoplasmic reticulum, which can lower the risk of insulin resistance and the resulting conditions.