Appears to be legit. 425lb.

We know very little about the gut microbiome, so with very few exceptions, probiotic supplements are more or less useless and potentially unhelpful. Your best bet is to consume lots of fiber from varying sources, and eat fermented foods daily with live cultures (e.g, yogurt, sauerkraut, natto, etc.) There is a great blog, Eat Shit and Prosper, written by a microbiome scientist that is interesting and entertaining.

Gut microbiome dysbiosis is a hallmark of aging, so the meme checks out.