Post-Exercise Hormone Predicts Biological Age

In that calorie restriction has been observed to extend lifespan in mammals, irisin – a newly-identified hormone released from muscle after exercise – is thought to induce similar effects by increasing adipose tissue will energy expenditure by adipose tissue. James Brown, from Aston (University United Kingdom), and colleagues enrolled 81 healthy men and women, ages 18 to 83 years with a mean body mass index (BMI) of between 20 and 30 kg/m2, in a study to assess whether a molecular link exists between circulating irisin levels and the length of telomeres – the endcaps of chromosomes which are thought to be a marker of aging. The team found that those subjects with  higher levels of Irisin also had longer telomeres.  Writing that: "relative telomere length can be predicted by age and plasma irisin levels,” the study authors conclude that: "irisin may have a role in the modulation of both energy balance and the ageing process.”