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Isoleucine

What Isoleucine is & what it does

Isoleucine is a branched-chain amino acid that occurs naturally in proteins and is used in cosmetics as a skin-conditioning ingredient. In a formula it can act as part of an amino-acid blend that supports the skin's surface and contributes to a smooth feel. As an amino acid it is also water-soluble and compatible with hydrating, lightweight products.

What does Isoleucine do in skincare?

Isoleucine is used as a skin-conditioning ingredient, often as part of an amino-acid blend that supports the skin's surface and a smooth feel. As an amino acid it is water-soluble and fits into lightweight, hydrating formulas. Its role is supportive rather than active.

Is Isoleucine safe?

Isoleucine is a naturally occurring amino acid and is generally regarded as well tolerated in cosmetic use. As with any ingredient, individual sensitivity is possible, so patch testing a new product is reasonable. This is general information and not medical advice.

Is Isoleucine vegan?

Isoleucine can be vegan, since it is often produced by fermentation or synthesis using non-animal sources. However, amino acids can also be derived from animal proteins depending on the supplier. Check with the brand if vegan sourcing is important to you.

Sunscreens with Isoleucine

We rate 32 sunscreens that contain it, showing the top 10 by overall score:

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