All health problems can be physical, chemical or emotional in nature.  Most people understand how emotional stress can contribute or cause certain types of health problems and pain.  

Everyone knows when the chemistry of the body is not normal, you can develop health problems, however the majority of people do not understand how and why many health problems can come about from physical causes. 

An example of how a problem can come about from something physical would be having a pebble in your shoe. You would feel pain from the pebble. The pain would not be from something chemical or emotional.  If you were in pain long enough this could lead to emotional stress and could perhaps even throw off your chemistry in the area, but the cause of the problem would still be something physical. 

The reason the person feels pain is because the pebble puts pressure on a nerve of pain.  If there was no nerve of pain in your foot you would not feel the pebble.

When you remove a pebble from your shoe, pain disappears because pressure or irritation to the nerve has been physically removed.  If there is pressure on nerves in the neck causing head or neck pain, when that pressure is relieved these problems will clear up. 

If there is pressure on a nerve inhibiting normal function, when that pressure is removed, normal function is once again restored. This explains why some people have gone to a chiropractic clinic for back pain and then recovered from a different problem altogether.  As they were treated to remove pressure from the nerves that were causing them pain, their digestive or breathing problems improved as well.