Earlier we found a high percentage of subnormal total glutathione (G(T)) levels in blood from elderly subjects and patients with chronic diseases. These findings suggested a hypothesis that high levels of G(T) in the blood occur in old persons who are in excellent physical and mental health. To this end, we recruited 87 white women who ranged in age from 60 to 103 years and reported that they felt healthy. Their health was verified with physical examinations, clinical chemistry profiles, psychosocial assessments, and blood G(T) determinations. This evaluation was performed in three waves over a 5-year period. The values were compared with those from representative individuals in this region and with normal national data. The results verified that these healthy subjects were in top physical and mental health. We also found that subjects of all ages had very high blood G(T) levels in waves I and II but only normal levels in wave III. These findings confirm that high blood G(T) concentrations and excellent physical and mental health are characteristics of long-lived women.