I dunno... there are studies that show what they are discussing, obviously, but I've taken milk thistle and had crazy good gains on cycles. Not sure if I'd have gained 10% more or something if I didn't take the MT but I personally didn't see any clear hindering of my gains from taking it. Thats just my opinion and I've yet to try Liv.52 with the same cycle again but I'll probably give it a shot. You will still get good gains, so don't think you are SOL. If you can do the non-MT containing products, then go for that to be 'safe' I suppose. Just don't skimp on cycle support... you need it haha. Thats just my two cents tho...