Tuesday, June 16, 2009 — A team of UNC researchers has proven that a key protein called p16INK4a is present in human blood and is strongly correlated both with chronological age and with certain behaviors such as tobacco use and physical inactivity, which are known to accelerate the aging process

as cells and tissues age, the expression of a key protein, called p16^INK4a, dramatically increases in most mammalian organs

p16^INK4a is a tumor suppressor protein, cancer researchers are interested in its role in cellular aging and cancer prevention

This is a major step toward a practical tool to clinically determine a person’s actual molecular, as opposed to just their chronological age

We found a very weak correlation between the biomarker and obesity – as measured by body mass index (BMI) – despite other data suggesting that caloric restriction slows aging. The data suggest the possibility that reduced exercise may actually be worse with regard to molecular age than a higher BMI