Water and its effect (or lack of effect) on bone or joint health?

In general, coffee is an acidic substance. Hence, it is quite logical that it would have some sort of negative effect of bone structure (since calcium is base). Moreover, I know for a fact that doctors recommend patients who suffer from osteoporosis to cut down on their coffee intake.

This is actually two different questions.  First, does drinking a lot of coffee affect the joints, and second might too much or too little water intake affect the joints.

 The coffee question is interesting to me because I have had a couple episodes where I was eating very badly or very little and drinking lots of coffee and my joints, in particular my hands, started hurting.  I never found any "hard" science evidence that coffee would affect the joints, but many of the more holistic type health people said that lots of coffee will affect the mineral balance in the body which may then affect the joints.  (As the previous respondent noted vis-a-vis calcium.  But I think other minerals were said to be involved as well.)  Arthritis is related to mineral activity in the body so this may be a factor.

 Being dehydrated or overly hydrated can affect the mineral balance in the body too.  Over-hydration can be quite dangerous because you excrete minerals with the urine.  But more than that I don't know.

I've done some searching on the Internet about this and based on all the answers I've found I can say a resounding "Beats me." 

I think it is more important to look at coffee and its effects on long term bone and joint health, instead of water ( or the lack of water ).  Most of the studies done on water concentrate on whether the water is flouridated or not.

Even the studies on coffee leave plenty of room for your interpretation.  Some say it contributes to loss of spinal bone density but not hip bone density, another says there is no detrimental effect at all as long as your drink only one to three cups a day. 

Just read carefully.

Seeing how our bodys are made of water and the studdies on water molecules show that it is not the intake but the thought put it to the water at the time of intake. So if you want to get the good stuff just think good things at the time. As for coffee I have no idea. Don't drink it.