Dry brushing mechanically removes dead skin cells from the surface, improving texture and allowing moisturiser to penetrate better. The stroking motion toward the heart does stimulate lymphatic flow and surface circulation, giving a temporary warming effect.
The claims about cellulite reduction and toxin removal are not supported by evidence. Cellulite is structural and cannot be brushed away. Toxin elimination is the liver and kidney’s job. Dry brushing is a pleasant ritual with real exfoliation benefits worth doing for those reasons.