After being put on only 20 mg of generic Zocor, I gained 10 pounds in a very short time period.  I also became so sore and stiff that I didn't want to even climb a flight of stairs anymore.  I am a physically fit person, daily treadmiller, good diet, yet a sudden weight gain and soreness that I could no longer ignore.  I quit my medication last week.  My mind is no longer foggy, stiffness and soreness is gone.  Now I'm waiting for the weight to come off!  I'm so glad for this web page.  I didn't make the correlation between weight gain and statins because it didn't mention it in the instructions from the pharmacy.  Now I know.