Caffeine in its pure form is a bitter, white substance that acts as a stimulant drug. Pure caffeine is an odorless white crystal or powder that is intensely bitter. In humans, it stimulates the central nervous system, temporarily warding off drowsiness and restoring alertness.

Caffeine is the main ingredient in anti-cellulite creams, temporarily dehydrating fat cells and making them smaller and the skin look smoother. As a vasoconstrictor, it’s used in de-puffi ng eye creams to temporarily tighten skin and reduce dark circles. By constricting blood vessels, it helps temporarily defl ate puff y eyes, reduce the appearance of dark circles, and minimize facial flushing. The acid in it functions as an antioxidant, and studies have found that caff eine may protect against sun damage to skin cells, and even repair damaged cells. Ground coffee beans are also an excellent exfoliant in scrubs.

It can be found in eye creams and anti-cellulite creams, sunscreens, and beauty products such as body washes, soaps, lip balms, and scrubs.