Stearic acid (SA) is a saturated fatty acid with an 18-carbon backbone (18:0). Although it is mainly abundant in animal fat, cocoa butter and shea butter are also very high in SA. It is also commonly used in detergents, soaps, cosmetics, shampoos, and shaving cream. Additionally, it can be synthesized in the body from palmitic acid. SA is not a strong substrate to make triglycerides compared to other saturated fatty acids and it generates a lower lipemic response. As compared to other saturated fats, SA doesn’t raise plasma LDL cholesterol. This may be due to absorption of SA and the amount of energy metabolized from it. In fact, SA may have some beneficial effects in regulating mitochondrial morphology and function, though these mechanisms are still being studied. The American Heart Association recognizes that a diet low in trans fats from industrial food sources and low in saturated fatty acids is optimal for cardiovascular health. SA is being studied as a solid-fat alternative to trans fatty acids in baking goods and shortenings since it is transfree, oxidatively stable, and doesn’t raise LDL cholesterol. (Unsaturated fats are not suitable for solid fat applications but are suitable for liquid fat applications, like frying.) However, the safety of using SA substitutes in industrial products is still being studied and debated.
References:
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Stearic C18:0
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