Cosmetic chemists are some of my favorite influencers in the skin-care space these days. Their approach to the subject through a technical, science-backed lens gives me intel outside of my expertise—the kind I can’t gather on my own by reading a press release or scanning an ingredient label. They know which ingredients play well together (and which ones don’t), and they can tell which ingredients are there for marketing hype versus efficacy. Here, some of the industry’s leading cosmetic chemists share their best under-the-radar skin-care tips.
Ramón Pagan
@glowbyramon, cosmetic chemist and product developer
“If an app on your phone is telling you a skin-care ingredient is dangerous, it’s not. Nothing that is used in commercial products is toxic or dangerous to you. Apps like Yuka and EWG are considered a scam in the scientific community because both are a result of people without scientific literacy trying to interpret complex data. They’re also the result of lobbying to manipulate the uninformed consumer. A lot of testing, safety assessments and toxicology are used to test and verify consumer safety with ingredients, such as if they absorb, up to what quantity, and an array of impacts they could have in the body. Even then, the amount approved for use in cosmetics is lower than the limit deemed safe to use, just to be more conservative. Therefore, if it’s used in a commercial product sold at a retailer, it’s a safe product. Also, no one wants a lawsuit. Big Skincare isn’t trying to hurt you.”
Julian Sass, PhD
@drjuliansass, cosmetic scientist
“The vast majority of ingredients are absolutely fine to use together, BUT keep an eye out for benzoyl peroxide and hypochlorous acid. These are strong oxidizers and can inactivate any antioxidants in other products, like vitamin C, retinol or niacinamide. For hypochlorous spray, you just need to let it dry before applying anything else on top of it, and for benzoyl peroxide, either use it in a leave-on product on its own without other actives. Or, use a cleanser with benzoyl peroxide and let it dry after rinsing it off!”
Kelly Dobos
Cosmetic chemist
The most underrated, overachieving skin-care product of all time? Petrolatum, aka Vaseline. It’s the humble goop in that big tub you can snag for less than $3. It’s a powerful occlusive that locks in moisture and protects compromised skin, and it also makes a great lip treatment. Its safety profile is exemplary, backed by over a century of use and regulatory scrutiny. Dermatologists love it, chemists trust it, and your grandma probably swore by it. Bonus tip: Petrolatum can even prolong the life of your fragrance. Apply a very thin layer to your pulse points—like your wrists or behind your ears—before spritzing your perfume. It slows down evaporation, helping your scent last longer. It’s a science-backed technique that costs pennies.”
Gloria Lu
@chemist.confessions, cosmetic chemist and cofounder of Chemist Confessions
“Hypochlorous acid may be one of the few ingredients we actually recommend storing in the fridge, but don’t put it in the freezer. This antimicrobial is quite unstable with a short shelf life. In fact, when purchasing hypochlorous acid sprays, we recommend not to buy in bulk. Fresh is definitely better here!”
Ginger King
@thebeautysharkginger, cosmetic chemist and president and CEO of Grace Kingdom Beauty
“Everyone is obsessed with ingredient lists, but ingredients are only half the story. What really matters is how they’re sourced and formulated. Two products can say ‘hyaluronic acid,’ but one hydrates while the other just sits there. Percentage matters, but more does not necessarily mean better because there is just so much the skin can take—the rest is a waste. It’s not about what’s on the label; it’s about the chemistry and formulation skills behind it. That’s where new beauty is born…yes, pun intended.”
Krupa Koestline, PhD
@krupakoestline, cosmetic chemist and biotech expert
“Packaging quietly makes or breaks everything. Light-and oxygen-sensitive actives, such as retinal, L-ascorbic acid, some enzymes and next-gen antioxidants, don’t belong in clear glass bottles with a metal-spring pump. That tiny coil can catalyze oxidation, and clear walls act like a tanning bed for your formula. If a product truly relies on sensitive, hard-to-stabilize actives, I want to see opaque, airless, low-headspace packaging and antioxidants/ chelators in the base to mop up trace metals. Otherwise, you paid for ‘vitamin C’ and are using ‘vitamin C’s eulogy’ by week six.”
Victoria Fu
@chemist.confessions, cosmetic chemist and cofounder of Chemist Confessions
“A vast majority of the data behind vitamin C is based on one specific molecule: ascorbic acid. It’s important to skim the ingredient list of vitamin C serums because many brands will label their serums generically as ‘vitamin C serum’ and will actually use vitamin C derivatives that are not ascorbic acid. Unfortunately, many of these vitamin C derivatives are not as well validated. However, there is a place for them because some skin types do not tolerate ascorbic acid as well. If you are in this group and prefer an alternative, I recommend sodium ascorbyl phosphate and magnesium ascorbyl phosphate.”
Stephen Ko
@kindofstephen, cosmetic formulator
“The SPF number on sunscreen products represents the average protection provided for a population, not an individual. That doesn’t mean you should fear or not trust an SPF number, but it should mean that you’re more attentive when applying. Apply a thick layer, reapply frequently and opt for a higher SPF. I personally like to apply my sunscreen in two layers to ensure a more even coat. Also, sprays, aerosols, powders, balms, foams and mousses are harder to apply sufficiently when compared to liquid and lotion formulas.”
Ron Robinson
@ronrobinsoncosmeticchemist, cosmetic chemist and founder of BeautyStat Cosmetics
“If you have sensitive skin, you may have tried ‘the sandwich method’ when using retinol, but did you know you can also do it with vitamin C? Instead of applying vitamin C serum directly to your skin, sandwich it by applying it over your moisturizer at night to lessen the direct impact of the active ingredient. Do this for a week or so to allow your skin to slowly adapt to this potent ingredient and still reap the benefits.”
