This day in age our bodies are under constant stress.  These stress responses can manifest into disease if not treated properly.  Our body doesn't know the the difference between  work deadline stress, being stuck in traffic or being chased by a bear.  It learns to adapt to the stress by releasing hormones to combat it.  Over time your body will give you signals that it needs to have more rest and digest time rather than being in fight or flight mode. You might notice pain and stiffness in joints, irritability, and lack of sleep creeping in.