Just to add another +1 to the anecdata points here, I had pretty bad acne well into my 20s, and experimented with a variety of measures for controlling it. The

Just to add another +1 to the anecdata points here, I had pretty bad acne well into my 20s, and experimented with a variety of measures for controlling it. The biggest win was to stop using ordinary soap to clean my face. Once I switched to just rinsing it with plain water, 70% of my acne disappeared. Some acne persisted around my nose and "T-zone" (the upper middle part of the face). I tried using a number of facial cleansers daily in the shower on just this area, and eventually found one that was far more effective than any other -- the brand is Aveeno and it has microbeads in it (which I heard are now illegal in the US). I'm now typically acne free, but to this day if I binge eat greasy foods for a couple days (the biggest culprit is pizza, followed by burgers), my face will start to get oily and pimples will start to form around my nose/T-zone. Also if I'm out in the heat sweating a lot, a bit of acne forms after a few days. Aside from these extreme situations I have very little acne. This all suggests to me that the face's microbiome plays a big role--too much soap or too much sweat are both capable of interfering with it, and too much oiliness probably blocks the pores. TL;DR more limited application of a milder cleanser seemed to be the biggest win for me. This experience led me to be judicious with soaps and other cleansers on the rest of my body as well--the stinky bits like armpits get soaped up and cleaned daily, but I pretty much just rinse the rest of my body in the shower unless I've been doing hard physical labor or something. My skin's very healthy and people say I smell good so it seems to be working.