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Leucine

What Leucine is & what it does

Leucine is a branched-chain amino acid that occurs naturally in proteins. In cosmetic and sunscreen formulas it is used as a skin-conditioning agent and can help support the skin's natural moisturizing factors. As a small, water-soluble amino acid it is generally well tolerated and contributes to a smooth skin feel.

What does Leucine do in skincare?

Leucine is an amino acid used in cosmetics as a skin-conditioning agent. It can help support the skin's natural moisturizing factors and contribute to a smooth, soft skin feel.

Is Leucine safe?

Leucine is a naturally occurring amino acid that is widely used in cosmetics and generally considered gentle and well tolerated. As with any ingredient, sensitivities differ between individuals.

Is Leucine natural or synthetic?

Leucine occurs naturally as one of the building blocks of proteins, but the leucine used in cosmetics is often produced through fermentation or synthesis for purity and consistency. Both natural and lab-produced sources are chemically the same amino acid.

Sunscreens with Leucine

We rate 17 sunscreens that contain it, showing the top 10 by overall score:

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