HPA Axis Dysfunction
The HPA Axis is a series of three glands (Hypothalamus, Pituitary, and Adrenals) that are primarily responsible for regulating our stress response in the body.
When we experience hypoglycemia, as I mentioned before, the brain goes into an emergency response to starvation. In addition to sugar cravings, the adrenals will release cortisol. Cortisol signals the release of stored glucose in the body (glycogen stores) to provide immediate energy.
Because of this response, glycogen stores are quickly burned up, hypoglycemia reoccurs, and the cycle continues. This is where HPA axis dysregulation promotes the onset of related symptoms while also exacerbating hypoglycemia-related issues.
With HPA axis dysfunction you are likely to experience a disruption in sleep. This is because cortisol is antagonistic to melatonin (meaning it opposes its function). When the HPA axis is thrown off, cortisol levels begin to fluctuate and interfere with the release of melatonin that occurs at night-time.
To review briefly, hypoglycemia stimulates the release of cortisol. Cortisol signals the release of stored glucose in the body, called glycogen, from the liver and muscle tissue. Cortisol is a stimulating hormone that can disrupt sleep if this response happens at night. This results in either insomnia or very poor quality sleep.
Although this cortisol response is helpful in emergencies, you want to try and minimize it as much as possible during keto-adaptation and especially at night.