Tons of friends end up posting about "getting healthy" and "starting a health challenge" on facebook, and without fail it's some "detox" and supplement and packaged crap program. Just saw another one this morning.
It's really hard not to post stuff like "So...what happens after that 21 days?" or "Wouldn't it be easier to just not eat crappy food?" or "I just put a note on my calendar to check in and see how your health is 6 months from now" or "I dunno; I like eating a bunch of bacon and being super healthy, but that's just me I guess."