According to the August 2, 2002, issue of Science - Postscripts - longevity in men - Brief Article

Nutrition Health Review, Spring, 2003

According to the August 2, 2002, issue of Science, three physiological measures have been associated with longevity in men: lower blood insulin levels, lower body temperature, and higher blood levels of dehydroepiandrosterone sulfate (DHEAS).

Further study is needed to provide a definite link between these values and a longer life, but gerontologists are eager to find a way to distinguish biological age from chronological age.