Your favorite soap may be one that smells good, lathers well, or just leaves your skin squeaky clean. Can it be irritating your skin? If you have itchy, dry skin between showers, you might want to consider whether the soap you're using is the culprit.
Soap is a surfactant, a substance that, when mixed with water, can remove dirt and oil from a surface to leave it clean. Soap is the natural result of a chemical reaction between an alkaline solution and a fat or oil, yielding alkali salts of fatty acids (the soap) plus glycerin. In contrast to soap, detergents are made without the fats and oils in an effort to avoid soap scum.
Soap can irritate the skin in a couple of ways. First, you can have an allergic response to a fragrance or dye added to the soap. Even if you have used the same soap for years, you could develop the allergy and suddenly respond to the soap in a way you hadn't before. The other way soap can irritate your skin is by stripping it of too much of the natural oils needed to keep your skin soft and elastic. If you suspect your soap is making you itch or drying out your skin, be sure to rinse well each time you wash, and consider choosing a different body cleanser such as mild cleansing product that isn't actually soap.