I have tried grapefruit, lemon and they were both hard for me...yuck. My last flush (4th) I did a little differently. I chased the OO (Olive-Oil) with Coke. I didn't mix them but just downed oil, then a swig of Coke until it was gone. By far, it was my most productive flush so far. Who knows if that is why, but it worked for me. :) I like the pineapple juice idea...I love it! This time I also held my nose when drinking the oil and honestly I did not taste it at all...whatever you do just don't let go until you are done!