Lipids are a large category of natural (plant based or animal based) ingredients insoluble or sparingly soluble in water but soluble in alcohols and organic solvents. This group covers from simply fatty acids to fat-soluble vitamins to waxes such as beeswax and steroids such as cholesterol.
This diagram shows the most important subcategories from a cosmetic chemist's point of view.
Lipids are basically classified into glycerides and non-glycerides. Fatty acids are present in glyceride skeleton but are found as stand-alone ingredients as well.
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