Bentonite clay is a natural volcanic ash derived clay known for its strong ability to absorb oil and impurities from the skin's surface, largely due to its negatively charged mineral structure that attracts and binds to positively charged particles like excess sebum.
A review of the scientific literature on clays used in cosmetics found supportive evidence for bentonite's oil absorbing and mild antimicrobial properties, making it a common ingredient in masks for oily and acne prone skin. A separate study evaluating a clay mask's effects on oily, acne prone skin found genuine improvements in oiliness and skin clarity after use.
Because it is so absorbent, it can also pull moisture from skin if left on too long or used too frequently.
Bentonite Clay References
The Scenario of Clays and Clay Minerals Use in Cosmetics/Dermocosmetics, Cosmetics, 2024
Comprehensive Assessment of the Efficacy and Safety of a Clay Mask in Oily and Acne Skin, 2023
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.
