Isn't All Soap Just Oil and Lye?
When it comes to cleansing products, you might think, “Isn’t all soap just oil and lye?” The simple answer is "Yes" but if you've ever encountered a "beauty bar" and thought it's just a fancy marketing term for soap, you'll realize that the real question is a little more confusing. To understand why, let’s look at the history of soap and its transformation during the early-20th century.
World Wars Changed Everything - Including How We Clean
In the early-20th century, one of the war time struggles was a shortage of animal fats used to make soap. Basic hygiene necessities coupled with the intense focus on war-time chemical research led to advancements in cleaning compounds, now commonly called "synthetic detergents" or "syndets". These man-made cleansers proved effective at removing dirt and oils. Over the next several decades, these cleansers were tailored across a wide range of applications from laundry to skincare to toothpaste to heavy-duty auto oil degreasers. Today syndets are so embedded in how we clean, that we don't really differentiate between detergents and soap [History of Soap source: American Cleaning Institute].
Detergents vs. Soap for Your Skin
When it comes to cleaning our skin, syndets can sometimes disrupt the skin’s natural barrier due to their ability to dissolve skin lipids, leading to dryness and irritation, particularly with frequent use. Sodium Lauryl Sulfate (SLS) is one example because it is a commonly used detergent but it comes with strict usage guidelines to minimize the risk of irritation. You can read more about it here. A more gentle syndet is called Sodium Cocoyl Isotheinate (SCI) and it is derived from coconuts. It has a great reputation as a mild cleanser, it's biodegradable, and it's one of the main ingredients in our foaming sugar scrubs.
On the other hand, traditional cold-process soaps, which rely on oils and lye, can be more gentle to the skin. The natural saponification process creates glycerin which is a natural humectant and draws moisture to the skin. The cold process method of making soap also provides the opportunity to preserve some unsaponifiable material within the soap, such as certain fatty acids or minerals. All together, this can create a nourishing bar of soap that can be less harsh to your skin.
Overall, research confirms that both cold-process soaps and sythetic detergents are effective cleansers that can maintain skin health and hygiene. Neither option will affect the pH-maintenance mechanism of human skin. Ultimately, you know your skin best and the best skin care routine for you may include one or both of these cleansers depending on the season or even your mood.
How does soap or cleanser actually work?
When mixed with water, soap molecules form a bubbly lather. These bubbles physically lift dirt, oils, and impurities away from the skin, allowing them to be rinsed down the drain. Standard soap is proven to be effective for cleansing, without requiring additional antibacterial agents or harsher chemicals. Both the CDC and FDA recognize that simple handwashing with soap and water is highly effective in removing pathogens from the skin, highlighting that extra ingredients often don’t add significant benefits for general hygiene.
This understanding of soap’s cleansing mechanisms and the benefits of naturally saponified soap reinforces the appeal of traditional formulas. They cleanse without compromising the skin’s natural defenses, maintaining a healthy balance ideal for everyday use.
Know Your Skin & Choose Your Ritual
While all soap may start with the basic ingredients of oil and lye, not all cleansing products fit this traditional mold. Understanding the differences between traditional soap and syndets gives us more control over our skincare routines, allowing us to choose the best product based on our skin’s unique needs and preferences. Whether you reach for a classic bar of soap or a fluffy whipped scrub, the best solution is the one that honors your skin and self-care routine.
