"Far from being the bad guy, cortisol is a hormone that's vital for our bodies and brains"

To complicate matters further, cortisol is also released in bursts, about every hour or so.

- by GINNY SMITH

This pattern changes gene activity and is vital for a whole range of functions.

One study investigating this recruited healthy volunteers, blocked their natural cortisol and substituted it with matching doses that mimicked either a daily (circadian) rhythm without pulses, or a circadian rhythm with pulses (similar to a natural release pattern).

The participants on the non-pulsed protocol scored worse on working memory tasks and reported poor sleep. Those on the pulsed protocol, however, were less able to accurately identify facial expressions, which is conversely linked to better mental wellbeing. The results suggest that it’s not necessarily the amount of cortisol in your system that affects your ability to function, but the pattern with which it’s released.