What sets alpha lipoic acid apart from most antioxidants is its dual solubility: unlike vitamin C, which is water-soluble, or vitamin E, which is fat-soluble, ALA works in both watery and oily environments within skin cells. This lets it neutralize free radicals in locations other antioxidants can't reach as effectively.
Research also points to ALA's ability to help regenerate other antioxidant systems in the body once they've been depleted, functioning as a kind of antioxidant recycler rather than working in isolation.
Alpha Lipoic Acid References
Biewenga GP, et al. The pharmacology of the antioxidant lipoic acid. General Pharmacology, 1997, as cited in Addor FAS, Antioxidants in dermatology, 2017
Saini RK, et al. "Alpha-lipoic acid and skin: a comprehensive review" — Dermatologic Therapy, 2021
Note: Lin JY, et al. "Alpha-lipoic acid is ineffective as a topical antioxidant for photoprotection of skin" — Journal of Investigative Dermatology, 2004
Our team reviews ingredient research and uses up-to-date evidence to rate ingredients based on the categories below.
Best
Ingredients with the most rigorous and convincing evidence. These are the standouts backed by consistent findings across independent, peer reviewed clinical research.. When we call an ingredient Best, it has earned that distinction through genuine, reproducible proof that it improves skin.
Good
Reliable, well tolerated ingredients that do their job without complaint. They may not carry the headline benefits of a Best rated active, but they hydrate, stabilize a formula, or support the ingredients around them in ways that make a real difference in how a product performs and feels.
Average
Ingredients that are perfectly safe and serve a clear function, typically as an emollient, thickener, or filler, but do not offer any meaningful skin benefit beyond that basic job. Not a red flag, just not a reason to choose one product over another.
Bad/Worst
Ingredients with documented potential to irritate skin, disrupt the barrier, or trigger sensitization in some users, often synthetic fragrance, drying forms of alcohol, or certain essential oils. Not automatically a dealbreaker for every skin type, but worth knowing about before you commit to a product.
