They studied levels of the stress hormone cortisol in 156 people, ages 54 to 71. Cortisol increases blood sugar levels and blood pressure in response to stress and can also cause changes in mood and memory.
The study found that cortisol levels tend to fall at bedtime but are usually high when people wake up and increase during the first 30 minutes after getting out of bed, BBC News reported.
"You've gone to bed with loneliness, sadness, feelings of being overwhelmed, then along comes a boost of hormones in the morning to give you the energy you need to meet the demands of the day," said lead researcher Emma Adam.
The findings appear in the journal Proceedings of the National Academy of Sciences. – (HealthDayNews)
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