Stress triggers many physiological changes in the body through the "fight or flight" response. When stress levels are high, levels of the hormone cortisol released into the bloodstream are also high. Studies confirm that chronic stress is associated with increased fat in the abdominal area, higher concentrations of blood sugar and insulin, higher blood pressure and higher levels of cholesterol—conditions that are associated with metabolic syndrome and that increase the risk of heart disease.
A recent small study published in the Annals of the New York Academy of Sciences suggests that older women who regularly practise meditation may have a reduced cortisol response to stress—and that the longer a woman has been practising, 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 (transcendental meditation) 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 practised meditation, the lower her cortisol response was. The study authors theorised that this lower cortisol response may reflect improvement of the endocrine system regulation and recommended that more research be conducted.