Insights:

1. Cortisol helps to regulate blood pressure, inflammation, blood sugar, thyroid function and more. When cortisol is persistently released, these systems do not function correctly.
2. When blood sugar is low cortisol is released to raise it up, but excess cortisol can lead to irritability (making people 'hangry').
3. Persistent stress keeps cortisol elevated. Diet can also keep cortisol elevated: eating inflammatory foods, and nutrient deficiency.
4. Regularly drinking black tea can reduce cortisol levels.
5. Improving magnesium levels can reduce cortisol.