Actually, in my experience so far, one of the better ways to bring down the body's tolerance, is to drink really strong green tea [Madura Green Tea With Paw Paw leaf is what I do reccommend] that has been brewed for at least two hours in a electronic travel mug [the kind Jaycar sells], or preferably all night at a constant temperature. Then when you do hit the marijuana leaf at last, you'll get so blazed you'll have trouble focusing your eyeballs, let alone move to masturbate.
True, if you drink enough tea bags [four, five or so... ] in a day, you'll get stoned on it, but it's NOT the same as marijuana... distinctly less pleasant.
Drink enough tea of this kind for at least a week, and you'll feel peppier and find yourself walking a lot faster, automatically with less effort. Keep it up long enough, and you may get a sensation of your body feeling like it's a shirt several sizes too tight. Then when that happens, you'll get an appetite like a teenager and put on a noticeable growth spurt... particularly if you've been making an effort to be healthy in your diet, etc, etc.
IMHO, marijuana is one of those recreational drugs that ACTUALLY requires you to keep your body as healthy as possible - it's worth the effort, as the reward is that one needs much less work to get reeeeaaaalllyy HIGH as a result, with less valuable leaf or bud used.
Have fun.