The fat in obese people is different than the fat in lean people, researchers said in a study Wednesday.
Obesity is a result of the body working improperly and the "sick fat" tissue doesn't work in the same way as that in a lean person.
Guenther Boden, lead author of the study published in Diabetes, said it's possible that "sick fat" could help researchers find out more about the ties between obesity and diseases such as diabetes, heart disease and stroke.
Researchers at the university took fat biopsies from the upper thighs of six lean and six obese patients and found considerable differences in the cells.
"The fat cells we found in our obese patients were deficient in several areas," Boden said. "They showed significant stress on the endoplasmic reticulum, and the tissue itself was more inflamed than in our lean patients."
Endoplasmic reticulum (ER) is found in every cell and helps synthesize proteins and monitor how they're folded.
The stress causes the ER to produce proteins that could lead to insulin resistance -- a major factor in developing conditions such as diabetes
Researchers say reducing weight can help reduce stress on the ER, and in turn lower the risk of insulin resistance.
Boden and other researchers are examining whether FFAs cause stress on the ER.
Plasma free fatty acid levels are increased in most obese people and raising these levels increases insulin resistance.
FFA-induced insulin resistance includes the buildup of fat.
"Obesity is associated with insulin resistance and with a low-grade state of inflammation," authors wrote. "Whereas the cause of neither is completely understood, there is good evidence to show that free fatty acids (FFAs) play an important role in the development of obesity-related insulin resistance and inflammation."
