A brand new peer-reviewed examine has evaluated the short-term pores and skin results of clay-based face masks, specializing in three generally used clays: purple, inexperienced, and black. The analysis, revealed this month within the scientific journal Cosmetics, factors to a transparent discount in pores and skin oiliness after software, however no lasting adjustments to pores and skin firmness or elasticity.
Researchers from the College of São Paulo and Lusófona College in Lisbon developed formulations utilizing every clay kind and examined them on contributors beneath real looking use circumstances. Not like each day skincare, clay masks are sometimes utilized for brief durations a couple of times per week. To mirror this, the examine used a two-hour contact time earlier than rinsing.
Oil management impact is evident, however short-lived
Throughout all examined formulations, floor oil dropped considerably after use. “All formulations considerably lowered superficial sebum ranges in comparison with the untreated management website, together with the placebo,” the researchers wrote.
The best focus (7%) confirmed the strongest oil-reducing impact. Nonetheless, two hours after elimination, sebum ranges had rebounded previous baseline. “There was no proof of a compensatory regulation induced by the clays,” the authors wrote, indicating the impact was rapid however not long-lasting.
For producers, the outcomes help the position of clay in oil-control merchandise, significantly rinse-off codecs, however recommend restricted potential for sebum regulation over time with out repeated use.
No measurable influence on elasticity or firmness
Regardless of claims usually linked to clay masks, the examine discovered no enchancment in pores and skin firmness or elasticity. “We didn’t observe important variations over time for any website,” the authors famous after analyzing cutometry knowledge.
The outcomes are per earlier research that query whether or not clay masks ship a lifting impact within the brief time period. For manufacturers selling anti-aging or firming advantages, these findings might underscore the necessity to again claims with long-term or repeated-use knowledge.
Formulators can draw on distinct clay properties
Every clay used within the examine introduced completely different mineral and bodily traits. Black clay had the smallest particle dimension, which can provide a smoother texture in software. Purple clay confirmed the best iron content material, supporting its use in photoprotective or pigment-rich formulations. Inexperienced clay was denser and contained smectite, a mineral linked to increased absorption capability.
These variations might inform ingredient choice relying on product targets, whether or not concentrating on oily pores and skin, bettering spreadability, or delivering visible results.
Heavy metallic ranges increase formulation issues
Ingredient security was additionally addressed. Whereas inexperienced and purple clays met U.S. FDA limits for heavy metals, black clay confirmed arsenic ranges above the allowable threshold to be used in shade components and “have to be extra precisely studied regarding achievement of arsenic limits,” the researchers wrote.
The discovering highlights a key consideration for manufacturers sourcing mineral components, which is that pure origin doesn’t eradicate the necessity for thorough testing and compliance verification.
The examine was designed to reflect typical client use of rinse-off masks, however the authors say additional testing is required to evaluate results over time or in several codecs. “Additional analysis is warranted to analyze the remoted results of every clay and their efficiency in several formulation autos and after repeated purposes,” they wrote.
Supply: Cosmetics, 2025,12, 219. doi: 10.3390/cosmetics12050219 . “Clay-Based mostly Beauty Formulations: Mineralogical Properties and Quick-Time period Results on Sebum Regulation and Pores and skin Biomechanics”. Authors: Sarruf, F.D., et al.
