A Cosmetic Chemist Explains Why Applying Water to Skin Doesn’t Hydrate It

By ·
A Cosmetic Chemist Explains Why Applying Water to Skin Doesn’t Hydrate It featured image
Getty Images

A somewhat counterintuitive-sounding truth: If the secret to healthy and hydrated skin was as easy as applying some water to it…well, those Sephora shelves would be rather stark.

As cosmetic chemist Marta Pazos succinctly explains, water won’t penetrate the skin’s barrier—in some scientific speak, skin is predominately hydrophobic, which means it’s not that easy to get through it—and the key to getting more moisture is finding a skin-care formula with ingredients that can “match the chemistry of the skin,” all while carrying some water along in the process.

Hyaluronic Acid (HA)

While she is quick to praise it, Dr. Marta admits hyaluronic acid is anything but lesser known, yet calls out the importance of understanding all its forms. “HA is a naturally occurring substance in the connective tissue. Chemically, it is made of a repeat unit not too different from glucose, and it is part of the cartilage, helping collagen keep in its desired state of hydration (which preserves it from degradation). The best formulations that incorporate HA should have a blend of different ‘sizes’ (or molecular weights) of this molecule to ensure penetration through the skin as well as a time-released ability for those larger ones that diffuse through the skin slower.”

A Synthetic Peptide

Besides HA in multiple sizes, Dr. Marta is also a huge fan of SYN-HYCAN, a synthetic tripeptide that can boost production of the body’s own HA. (Pro tip: Our bodies tend to like best what they produce, as opposed to what we put into them.) “When properly formulated, this ingredient can penetrate deep into the layers of the skin, and it is believed to not only boost hydration, but also collagen production,” she says.


You’ve likely seen this ingredient on the label and wondered-what-the-heck it was, but Dr. Marta is quick to classify it as another wonder ingredient. “It loves water, is a small molecule and fairly compatible with skin—which translates into the ability to drag hydration deep into the layers of the skin, a place where it is not only very necessary to get to, but hard to get into.”


They may have a reputation for being drying, but Dr. Marta likes clays for a quick hydration boost. “They come ‘premoistened’ in a formula, which means they are already dissolved in water, and can redistribute hydration to ensure that it goes where most needed.”

Cellulose Derivatives

These are the complicated-sounding names that can create a perfect hydration layer on the skin, protecting it and leaving a nice, silky feel behind. Dr. Marta also says they are “great in water-based serums for very oily skin type that can be prone to clogging when using regular moisturizers.”

Vitamin B3 (niacinamide)

No matter what you call it, the super vitamin can penetrate skin and drag water, while also acting as a collagen-production stimulant (i.e., it increases elasticity). Best when formulated with HA for hydration purposes, it also helps with reducing inflammation, reducing hyperpigmentation and it’s an antioxidant.

Sucrose and Sodium chloride

These “so understated and so underrated ingredients” are great at “fixing” water and helping skin to avoid hydration loss. As Dr. Marta says, they are so readily available, inexpensive and incredibly easy to incorporate into formulations. “In that same note, honey must also be considered, which also has amazing antiseptic properties.”

Related Posts

Find a Doctor

Find a NewBeauty "Top Beauty Doctor" Near you

Give the Gift of Luxury

NewBeauty uses cookies for various reasons, including to analyze and improve its content and advertising. Please review our Privacy Policy and Terms of Use for more about how we use this data. By continuing to use this site, you agree to these policies.