The present invention relates to a method of treating osteoarthritis by administering a mineral composition in the form of a nutritional supplement, where the mineral composition may contain Smectite, Gypsum, Quartz, Feldspar, Jarosite, Kaolinite andor Zeolite. Electrolyte precursor powders are fed to a continuous blender type mixer using precision metering equipment that controls material feed rates. The invention is suitable, for example, for enteral nutrition lines.