Medical advice of questionable (at least, in the speaker's opinion) nature/origin, especially if it involves something undesirable, such as yucky-tasting foods/supplements, unwanted or disagreeable adjustments in diet/lifestyle, excessively strenuous exercise, etc.
My doctor wants me to lose weight, eat salads and vegetables, give up red meat and beer, exercise, and take a whole bunch of hard sticky pills and bitter powders! Yeah --- RIGHT!! Like I'm gonna sweat and toil and withstand that kinda TORTURE just for my HEALTH?! Heck, I'd rather live with my maladies and die a few years sooner than suffer with all of his quackola... what good is living a bit longer if you're hungry and miserable all the time?!?!???