studies in humans suggest that leukocyte telomere length may act as a marker of biological aging. We investigated whether individuals in the Nicoya region of Costa Rica,known for exceptional longevity,had longer telomere length than those in other parts of the country. After controlling for agg,age squared,rurality,rain season and gender,
the mean leukocyte telomere length in Nicoya was substantially longer (81 base pairs,