Ingredient guide
What Is Castile Soap? Ingredients, Uses and Myths
Castile soap started as olive oil soap from Spain. Today the word usually just means soap made from plant oils. Here is what is inside, how it is made, and the myths to ignore.
Ingredients
Plain-English guides to what goes into soap, from lye and glycerin to olive oil, goat milk and essential oils, and what each ingredient actually does.
5 articles
Every bar of real soap starts with fats, oils and lye. The guides below explain what each common ingredient does, where it comes from and what to look for on a label. New here? Start with what castile soap is, then read about olive oil in soap and the debate over palm oil.
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Ingredient guide
Olive Oil in Soap: Why It Makes Such a Gentle Bar
Olive oil is the classic soap oil behind castile and Aleppo soap. Here is what it brings to a bar, its trade-offs, and how to spot it on a label.
Ingredient guide
What Is Aleppo Soap? Olive and Laurel Oil Explained
Aleppo soap is a traditional Syrian soap made from olive oil and laurel berry oil, then aged for months. Here is how it is made and what the laurel percentage means.
Ingredient guide
What Is African Black Soap? Ingredients, Uses and Cautions
African black soap is a traditional West African soap made with plant ash and oils. Here is what goes into it, what the evidence says, and how to use it without drying your skin.
More in this topic
Ingredient guide
Palm Oil in Soap: What It Does and How to Choose Responsibly
Palm oil is common in bar soap because it makes hard, long-lasting bars. Here is why makers use it, the deforestation concerns, and how to read palm and RSPO labels.