Is There Lye in the Soaps?

By definition soap is the result of a chemical reaction between an acid (the fats and the oils) and a base, sometimes called a caustic (the lye). This is true of all soap even those made by Proctor and Gamble and their competitors. This is also the definition of soap (paraphrased) sanctioned by the FDA.

But the answer to the question: “Is there lye in the soap?” is “No” because while lye is required to make soap, it is chemically changed in the process of making soap and is no longer lye. Here is how it works:

What’s required to make soap:

Lye (NaOH) is made up of Sodium (Na) and Hydroxide molecules (OH).


Fat is made up of Fatty Acids and Glycerol.


When the lye and the fats are mixed together a chemical change takes place that destroys the bonds of the sodium and hydroxide and the fatty acids and the glycerol. They are no longer combined and are free agents that recombine and change partners with the other elements.

lye3 lye4lye5lye6

And this how they recombine and change partners.


This is true soap.


This is glycerine – note that handcrafted soap is about 25% glycerine.

So – while you need lye to make the soap – there is NO lye in handcrafted (or any other) soap.