@bfree - I agree with you in part about endorphins and exercising however I'm not in complete agreement with your thoughts on painkillers.
There are millions of people suffering from some very serious illnesses like cancer and AIDS. These people's immune systems are greatly affected by their diseases.
And because certain diseases create a deficiency of endorphins their bodies require prescribed medications to help boost those powerful painkilling cells.
I agree with you also that in many cases it appears that painkillers are being abused not only by the patients but through the medical industry as a whole.
But when it comes to serious diseases that cause cell death, prescription medication is the only option they have to boost and increase the bodies natural endorphins and enkephalins restoration levels.
I'm sure most people understand the importance of the enkephalins function to help ward off diseases, but when the disease itself has destroyed the enkephalin structure, than they no longer have the ability to fight it through endorphin inducing exercises.