I take the OPC also which has a lot of health benefits and not only is CalX great to add to it for better health, it enhances the flavor as well.
It is isotonic—works great and I feel better using it—especially my knees feel better after using this fantastic product. I was an Airborne soldier and landed hard many times this helps me Buy and become a satisfied user I did!!
I mix it with my OPCXtra and take every day.
Really enjoying the OptiHealth product line.