A person who is overweight and has reduced sensitivity to the hormone insulin may be aging prematurely, according to new research.
Such people develop diseases associated with aging, such as type 2 diabetes and heart disease, earlier than normal. However, the mechanism by which being overweight and having insulin resistance lead to age-related diseases has been unclear.
To see whether obesity and insulin resistance affect aging at the cellular level, Gerald Berenson of the Tulane University School of Medicine in New Orleans and his colleagues examined blood samples drawn at least 10 years apart from participants in the ongoing Bogalusa Heart Study. The focus of the study, which has been running in Bogalusa, La., since 1973, is to identify cardiovascular-disease risk factors over the course of people's lifetimes.
The researchers analyzed white blood cells from 49 study participants. The team measured the length of telomeres on the ends of the chromosomes. These pro