"Glucosamine is fine but don't bother with the additions some firms mix with it (e.g. chondroitin) says my osteopath!"
"Glucosamine, a sugar amino-acid, helps form the "network" of strands covering the joint surfaces of bones. Chondroitin is the cartilage itself, which is then laid down upon that network. The two substances are symbiotic and must be used together, which is why manufacturers package them together. To take one without the other is tantamount to useless."


Well, a little knowledge is a dangerous thing...

Both such chemicals are useful, Some 'counter self medications' also include many other things including omega 3&6, various minerals, etc.

There is an old saw... "moderation in all things except moderation itself". This applies to both the taking of 'drugs' and physical exercise.