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How Body Soap Works

Body Soap Chemistry

Maybe you have several different kinds of body soap sitting around your house. There's the old standard bar of deodorant soap that usually sits on your shower shelf, the pump of antibacterial soap next to the kitchen sink, the shower gel and loofah sponge you received as a gift, and that small bottle of body wash from the hotel you stayed at during your last vacation. All these products have at least one thing in common: They clean. The difference is in how.

Water alone can wash away dirt from your skin by sheer force, but because water doesn't mix with oil, it is ineffective in removing oily buildup [source: Ophardt]. In order to get rid of excess oils from your skin, soaps have to have bonding power. True soap is made up of fatty acids, which contain a chain of connected hydrogen, carbon and oxygen atoms. One end of this chain is lipophilic - it is attracted to oils. The other end of the chain is hydrophilic, or attracted to water [source: The Soap and Detergent Association]. When you lather up, the lipophilic ends of the molecules pick up the grease and oils on your skin. When you rinse, the hydrophilic ends of the molecules follow the water, letting you rinse the soap molecules -- and their attached impurities -- away.

When picking out your body soap, you'll want a product that can wash away the dirt and extra oils from your body. However, you'll also want a soap that doesn't strip away the natural oils that should be in your skin. Removing too many of the oils from your body will leave your skin dry, flaky and irritated. Ideally, your body soap should remove the oils you don't need and leave the moisturizing oils behind.

Chemistry lesson aside, if you're ready to lather up, read on to find out what you can expect from bar soaps.