A recent small study published in the Annals of the New York Academy of Sciences (2004; , 211–15) suggests that older women who regularly practice meditation may have a reduced cortisol response to stress—and that the longer a woman has been practicing, the less likely she is to react to stress with high levels of blood cortisol.
Walton and colleagues studied 30 women, 16 who were long-term practitioners of TM and 14 controls, all between the ages of 65 and 92 years. The subjects ingested 75 grams of glucose in order to stress their systems metabolically. Cortisol levels were measured before and after administration of the stressor. The researchers found that cortisol levels rose much higher and with greater speed among the controls than among the meditators. Moreover, the longer a subject had practiced meditation, the lower her cortisol response was. The study authors theorized that this lower cortisol response may reflect improvement of the endocrine system regulation and recommended that more research be conducted.