It still has notable impact on your gut microbiome, including bacterial species and total load.
"Rapamycin is a natural macrolide compound isolated from bacteria and a pharmacological inhibitor of TOR signaling. It can reduce the rate of aging and effectively improve age-related diseases.Citation110 Rapamycin treatment has reportedly altered the number and structure of gut microbiota in flies and mice. The addition of rapamycin to food can significantly reduce the bacterial load of flies (40 days) and delay microbial expansion in the aging gut.Citation93 It also reduces the level of Alphaproteobacteria, which is a group that has been previously recognized to be related to a decline in health and mortality in the elderly.Citation94 In middle-aged mice, transient rapamycin treatment is also associated with microbial remodeling, including a dramatically increased prevalence of segmented filamentous bacteria in the small intestine.Citation95 However, only a few studies have investigated the interaction between rapamycin and gut microbiota. Therefore, whether the change in gut microbiota plays a causal role in the beneficial effect of rapamycin treatment remains to be answered."
Don't get me wrong, it's exciting and super.promising, I'm just going to opt for the compound with zero evidence of gut microbiome impact.
Once we know more with Rapamycin, maybe. But for now, I spend way too much on specific bacterial colonies to turn into yogurts to risk undoing that work, lol.