Since heart disease is the leading cause of death in the U.S., maintaining our heart health should be at the top of our to-do list each morning. Chronic sleep deprivation directly influences the adrenal cortex to release more cortisol into the bloodstream. 
This rise in cortisol increases receptor sensitivity to norepinephrine and epinephrine, causing an increase in heart rate. Being sleep-deprived for even five days out of the week can immensely increase the workload on the heart if looked at it on a scale of twenty to thirty years. High cortisol levels also directly decrease inflammatory and immune responses. This is why you are more likely to catch a cold when you have been sleep-deprived for a period of time. The next time you crawl into bed, try to get at least seven hours!
Written by: Student Doctor Navpreet Singh Badesha
