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Thioctic Acid

What Thioctic Acid is & what it does

Thioctic Acid, also known as alpha-lipoic acid, is a sulfur-containing compound that occurs naturally in the body and is used in skincare as an antioxidant. In formulas it helps neutralize free radicals and is sometimes added to support a smoother, more even-looking complexion. It is both fat- and water-compatible, which lets it work across different parts of a formulation.

What does Thioctic Acid do in skincare?

Thioctic Acid, or alpha-lipoic acid, acts as an antioxidant in skincare formulas, helping to neutralize free radicals. It is sometimes included to support a smoother and more even-looking complexion. Because it is both water- and oil-compatible, it can be formulated in a range of product types.

Is Thioctic Acid safe?

Thioctic Acid is widely used in cosmetics and is generally considered safe at the levels found in skincare products. As with many active antioxidants, some people may find it irritating, especially at higher concentrations. If you have sensitive skin, patch testing a new product is a sensible precaution.

Is Thioctic Acid natural or synthetic?

Thioctic Acid occurs naturally in the body and in some foods, but the version used in cosmetics is typically produced synthetically for purity and consistency. The synthetic material is chemically the same compound. This makes it reliable and reproducible across formulations.

Sunscreens with Thioctic Acid

We rate 25 sunscreens that contain it, showing the top 10 by overall score:

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