Silymarin is a group of antioxidant compounds extracted from milk thistle seeds, best known as a liver supporting supplement but also studied for skin.
In mouse studies, applying silymarin before UV exposure meaningfully reduced the oxidative stress and inflammatory immune response that UV light normally triggers in skin, pointing to a real protective, antioxidant mechanism.
Separate laboratory research has found that silymarin can help calm skin inflammation and reduce the activity of enzymes that break down collagen. Because most of the strongest evidence comes from animal and cell based studies rather than large human trials, its topical use in skincare is considered promising but still developing.
Silymarin (Milk Thistle Extract) References
Silymarin, a Flavonoid from Milk Thistle, Inhibits UV Induced Oxidative Stress Through Targeting Infiltrating CD11b+ Cells in Mouse Skin, Photochemistry and Photobiology, 2008
Silymarin Inhibits Dermal Gelatinolytic Activity and Reduces Cutaneous Inflammation, 2024
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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.
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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.
