Cortisol is a substance released by the adrenal glands under stressful conditions and is widely considered to be a reliable marker for an individual's response to, and recovery from, stress. Cortisol levels start high in the morning and steadily decline over the course of the day with intermittent rises as stressors arouse the adrenal gland. The slope of the hormone's daily decline is believed to be correlated with well-being, with steeper declines reflective of better health and shallower declines predictive of health problems. A study of 30 couples in Los Angeles asked them about their marital satisfaction, got them to monitor their stress levels throughout the day and monitored the participants' cortisol levels. The study found that cortisol levels dropped further among happily-married women than less happily married ones suggesting that those with poorer marriages didn't recover from the stresses and strains of the workplace as well. Long-term elevated cortisol levels have been associated with depression, burn-out, chronic fatigue syndrome, relationship problems and poor social adjustment. The men's cortisol levels declined just as quickly after work whether they were happily or unhappily married.
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