So what does cortisol really do, and what does it effect?


Also called the “stress hormone” cortisol is a big player in influencing, regulating and modulated a lot of the changes that take place in the body when responding to stress. Including things such as: blood sugar levels, the metabolism of fat, carbs and proteins, immune response, blood pressure and CNS. (central nervous system activation)

All of these actions will be a contributing factor to muscle gain or fat loss and your overall progress towards your fitness goal.

So maintaining an optimal amount of cortisol in your blood is critical on your journey. Optimal levels of cortisol range from 6-23 micrograms per 100ml – towards the higher end of the spectrum in the mornings.


Prolonged high levels of cortisol may result in:

  • Impaired cognitive performance
  • Blood sugar intolerance
  • Sleep disruption
  • Slow wound healing
  • Dampened thyroid function
  • Decreased bone density
  • Decreased muscle mass
  • Lowered immune function
  • Increased body fat


Prolonged low levels of cortisol may result in:

Brain fog/ mild depression

Low thyroid function

Blood sugar imbalance


Sleep disruption

Low blood pressure

Lowered immune function