why the level of cortisol rises in the morning?

Answer:
Circadian clock regulates cortisol production.It is at it's highest at about 4 am and then your body uses it up during the day as necessary.

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cortisol is a long-term stress hormone, and at night you r relaxed, you don't need cortisol that much, while in the morning you need attention

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Any hormone for that matter is at its high levels in the morning. The time betwen 11pm to 3 am is when we are supposed to relax and our metabolic rate decreases. This is the time when our hormonal levels gradually increase reaching a peak in the early mornings. This increased level helps us to sustain the whole day again repeating the process again and again.

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