Why is cortisol production so important. Any ideas?

Needed to live! Cortisol is a hormone whose production on a daily basis helps keep us healthy. Without it, blood vessels cannot respond to other hormones (such as epinephrine), which results in an abnormally low blood pressure. Many other symptoms can accompany a lack of cortisol (adrenal insufficiency), such as weakness, fatigue, anorexia, nausea, constipation, abdominal pain, and weight loss.