Myth #8: It Can be Made Without Lye

No Lye, No Soap… And That’s No Lie!

I’ve come across claims about making soap without using lye, but here’s the truth: you can’t make true soap without it. Soap is created through a chemical reaction called saponification, which requires an alkali—most commonly sodium hydroxide (for bar soap) or potassium hydroxide (for liquid soap). Without an alkali, saponification cannot occur.

Making “No-Lye Soap”… Chemically Impossible

Some sources suggest that soap can be made without lye by using methods such as melt-and-pour (M&P). M&P involves pre-saponified soap that can be melted in a microwave and reshaped. After my first Christmas of gifting M&P creations and the shredded to liquid soap, the creative bug in me craved a bigger challenge. That desire led me to devote six months to researching the art and science of soapmaking. When I finally made my first loaf of cold-process soap, I was hooked—seriously hooked—and I’ve never looked back!

This terminology can be misleading, particularly for those unfamiliar with soap chemistry. For instance, someone using M&P might believe they’ve created a lye-free soap and could even gift it under that impression. While the intention may be to avoid handling lye directly, the base soap used in M&P has already been fully saponified using lye.

Then there’s the method of shaving a bar of soap, dissolving it in hot water, and calling it “lye-free” liquid soap. Spoiler alert: it’s still not free of lye, because the original soap was created through saponification. In addition, the resulting mixture is unstable and typically congeals or separates over time.

Years ago, I tried both approaches for making gifts. Even then, I understood that I wasn’t eliminating lye from the process—I was simply using products in which saponification had already been completed.

What Does the FDA Say About Soap?

The FDA defines soap as being made “by combining fats  or oils and an alkali, such as lye.

In short, without an alkali such as lye, soap cannot be made. This is a fundamental requirement of the chemistry of saponification.