Common Types of Bar Soap

Not All Soaps Are Created Equal

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Not all soaps are made the same. Did you know that so-called "cleansing" soaps can actually be the most damaging to the skin? Soaps vary as far as their chemical makeup and clinical effects. If you've ever dealt with skin issues that may have been exacerbated by the kind of soap you use, you'll want to read on.

How Soap Is Made

There are several ways to make soap, but traditional, made-from-scratch soap is made by mixing animal or vegetable oil, water and lye, a process known as saponification.

Many soaps include added fragrance, colors, essential oils and other ingredients, although they are not necessary components in a typical bar of soap.

Lye is an extremely caustic, alkaline, chemical solution used in many cleaning products. The amount of lye used to make soap depends on the type of oil that is being used. When mixed with water, solid lye dissolves and the water heats up. Lye is an extremely dangerous material to work with because it's so abrasive. It can cause severe burns, even if it only comes in contact with skin for a couple of seconds.

There are two types of oils used to make soap: vegetable and non-vegetable (animal).

Vegetable Oils

Non-Vegetable Oils

  • Tallow (beef fat)
  • Lard (pig fat)

Types of Soap

There are many different types of soap, from laundry soaps, to kitchen cleansers, to medicated soaps. Different soaps are made with different ingredients, which vary depending upon the soap's purpose.

For example, laundry detergent does not contain the same ingredients as a medicated bar of soap. These are some of the most common:

Common Bar Soaps

Common bar soaps contain the most aggressive surfactants, which reduce surface tension between oil and water and keep them from separating. Surfactants do the best job of picking up dirt and grime from the skin and washing it away.

However, surfactants do not completely rinse away, and they also have high pH levels, making them irritating to the skin. Common ingredients found in ordinary bars of soap include sodium tallowate and sodium cocoate.

Superfatted Soaps

Superfatted soaps are created using a process called incomplete saponification. Soap is made according to the typical saponification process, but chemicals are added, which prevents some of the oil or fat from being totally processed. The superfatting process improves the soap's moisturizing abilities and makes it less irritating to the skin.

Transparent Soaps

Transparent soaps are just like common bar soaps, but that have added glycerin, a moisturizer. The components of transparent soaps are still irritating to the skin, but the glycerin helps make the soap​ milder.

Syndet Bars

Syndet bars are made from synthetic surfactants. These surfactants are made from oils, fats or petroleum products that are processed in some way other than saponification. These synthetic surfactants make syndet bars the mildest personal cleansing bars.

Dove®, which was launched in 1955, was the first syndet bar produced. Common ingredients found in syndet bars include:

  • Sodium cocoyl isethionate (the most widely used)
  • Sulfosuccinates
  • aApha olefin sulfonates
  • Alkyl glyceryl ether sulfonate
  • Sodium cocoyl monoglyceride sulfate
  • Betaines

Combination Bars

Combination bars are exactly what they sound like. They are a combination of different types of cleansers designed to maximize cleansing while minimizing irritation. These bars commonly combine ingredients of superfatted soap and syndet bars. Combination bars are less irritating than soaps, but less mild than syndet bars.


Abbas, Syed, Goldberg, Jessica, and Massaro, Michael. "Personal cleanser technology and clinical performance." Dermatologic Therapy. Vol. 17 2004: 35-42.

Ananthapadmanabhan, K., et al. "Cleansing without compromise: the impact of cleansers on the skin barrier and the technology of mild cleansing." Dermatologic Therapy. Vol 17 2004: 16-25.

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