It's exfoliation, nothing more. The stiff bristle dislodges dead cells from the skin's dead outer layer before they'd flake off on their own. Same job a washcloth, a salt scrub, or a lactic-acid lotion does, by a different route. Bristles don't reach the living skin underneath at normal pressure.

The pink flush is blood, not lymph. Friction makes small vessels near the surface widen; the whole skin surface flushes at once, so it feels systemic, but it stops at the skin and fades within the hour.

There is no trial of dry brushing at all — not for smoother skin, ingrowns, cellulite, or lymph. The nearest real evidence is on kanpumasatsu, a Japanese dry-towel rubdown: a five-minute session nudged up pulse, temperature, and blood oxygen, like light exercise ¹, on a base the reviewers call thin and unsettled ². A cotton towel is gentler than a brush, and those studies are tiny. Exfoliation is real because exfoliation is well-studied; the brief alertness lift is plausible. Everything past that has nothing under it.

The pressure is the whole game. Start conservative and let your skin set the pace.

If you shave, this is where it earns its keep. Legs, bikini line, neck, chest — brushing the follicle mouths clear before a shave gives curling hairs a straighter exit, and pre-shave exfoliation is a standard fix for razor bumps. Brush the night before or on a non-shave morning, never right after shaving. Keratosis pilaris, the rough bumps on upper arms and thighs, is the other spot where it visibly helps, though a lactic- or salicylic-acid cream beats mechanical scrubbing for it ³.