Lol I love that people are in here assuming I just pulled lemon juice helping kidney stones out of thin air. It is good to be skeptical, but not without doing your due diligence. Google is both user friendly and effective.
Y'all, you just got educated by a bartender. Remember that the next time you assume you're better than your waitstaff. (Not you, person I'm replying to, but the armchair naysayers).