Some thoughts from Doug: Evolution isn’t perfect
If our bits and pieces work well enough to survive long enough to produce another generation evolution will tend to keep them. The appendix, tonsils, thin skin, low backs, necks, shoulders, balance, anxiety, autoimmunity and quite a few others things just strain, tear and malfunction often for no apparent reason. How annoying!
Our old active (but short and dangerous) lives have been replaced by safe (but longer and sedentary) ones. As a result our lifestyle can weaken our bodies. Everything from joint strain and limb pain to metabolic diseases such as high blood pressure and diabetes is made far worse simply because we no longer move around. But knowledge is power and understanding what increases the risk of injury and malfunction is often extremely useful.
Our job in many cases is simply to get people going, keep them going and encourage activity. It this last very simple but significant element of the health care puzzle which does most of the good work.