Why do lips get drier than skin? What the barrier shows

Your cheeks can feel fine at noon on a cold day while your lips already feel tight enough to crack when you smile. It is tempting to blame the weather or the lip balm you forgot at home. The better answer to why do lips get drier than skin sits in the lip surface itself, which is built less like facial skin than it looks, and which researchers can measure losing water in real time.

Why do lips get drier than skin?

Lips dry out faster because their surface holds less water and lets more of it escape. A dermatology study compared the lips and cheeks of 303 healthy women aged 21 to 80, measured in winter. Water loss through the lip surface was almost three times higher than through the cheek, and surface hydration on the lips was about one-third of the cheek’s.

Those numbers are striking because the cheek is not a dry-skinned comparison. The same researchers point out that the cheek already loses water faster than most other parts of the body. The lips outpaced it by a wide margin.

The authors also looked at the cells on the lip surface. On most skin, the outermost cells finish maturing into flat, tightly packed corneocytes that form the barrier. On the lips, those cells were larger and still carried traces of their nuclei, a sign they had not fully completed that process. The study concluded that this incomplete maturation explains the lips’ poor barrier and their low ability to hold water.

How is skin on the lips different?

The lip is the one place on the face where the lining of the mouth is permanently exposed to the outside, and its barrier reflects that. It sits between the skin of the face and the moist lining inside the mouth, and it behaves like neither.

A 2016 study of 41 women tied rough-looking lips to the lipids in that surface layer. How rough a person’s lips looked tracked with how little water the surface held, and with the levels of specific ceramides, the fats that help seal the barrier, rather than with the total amount of ceramide alone. A separate study found that people with dry lips have lower water-holding capacity, weaker barrier function and lower ceramide levels on the lip surface.

Even the two lips differ. A 2025 study of healthy volunteers in southern China found the upper lip held more water and lost less of it than the lower lip. If your lower lip is always the one that cracks first, that is consistent with the measurements.

Why do lips get so chapped in winter?

Cold, dry air weakens skin’s barrier in general, and the lips start with the weakest barrier on the face. A review of climate and skin concluded that low humidity and low temperatures lead to a general decrease in skin barrier function and make skin more reactive to irritants.

If you notice your lips tightening in the same weeks your hands start to feel rough, the cause is likely the same air working on two barriers of different strength. Our piece on whether misting your face before moisturizer helps explains why water alone evaporates in dry air unless something seals it in, and the same logic applies to lips.

Does licking your lips make them drier?

It makes things worse, not better, because saliva adds water that leaves again within moments. Licking is such a strong influence on lip measurements that researchers developing a way to test the lip barrier fitted volunteers with a dental tongue-fixation device, to stop them from moistening their lips on purpose or without noticing.

That detail is useful in daily life. If your lips are dry, the urge to lick them is constant and mostly unconscious. A balm within reach breaks the loop more reliably than trying to remember not to do it.

What actually helps dry lips?

A balm built on oils, waxes or butters helps, because it slows the water loss the lip surface cannot control on its own. In a 2019 study of 15 women, one application of a lip product made from a fruit wax, coconut oil and olive oil improved lip hydration and barrier readings, and the lipids stayed in the lip surface for two to six hours.

Ceramide-based balms have been tested too. In a four-week study of 30 people with dry lips and self-described sensitive skin, a lip balm containing a synthetic ceramide was used at least twice a day. By the end, 27% were judged markedly improved and 60% improved, with no adverse events recorded. The study was run with the manufacturer, so read it as one product’s result rather than a general rule.

What to leave out matters as much. Flavorings are the ingredient most worth checking if a balm seems to make your lips worse: a case series described four people whose lips reacted to peppermint oil in a lip balm, confirmed by patch testing. A plain, fragrance-light balm is a sensible first choice if your lips are already irritated.

Editor’s note

My lips are very dry, more than any other part of my face, and the lip product in my routine is SKINFOOD’s Avocado Stick Lip Balm. Its key ingredients are avocado oil and mango seed butter, which puts it in the oils-and-butters group the studies above describe. Reading the lip research explained something I had only noticed: the rest of my face can be comfortable while my lips are not, because the two surfaces are simply not built the same way.

Do lips need SPF?

Yes, when you are outdoors, a lip product with SPF is worth wearing, because lips get the same sun as the rest of your face and are easy to forget. In one study, the lower lip seemed to tolerate more UV before reddening than back skin, which the authors put down to its constant exposure to sunlight. The same study found that a lipstick sunscreen’s measured SPF on the lip was two units lower than the figure measured on back skin.

There is a moisture benefit too. In a three-month study of 140 people, those who applied a sunscreen lipstick three times a day had higher lip hydration by the end than those who applied nothing. Reapplication is the practical problem: lip products wear off when you eat and drink, so a stick you can reapply is more useful than a higher number you only put on once. For the rest of the face, our guide to how much sunscreen to use on your face covers the amount.

How do you take care of dry lips?

Treat lips as a separate area with a weaker barrier, not as an afterthought to your moisturizer. A few habits follow from the research:

• Apply balm before your lips feel dry, especially before going out into cold air or into a heated room.
• Keep a balm where your hand reaches for it, so it replaces the urge to lick.
• Use an SPF lip product outdoors and reapply after eating or drinking.
• If a balm stings or your lips get redder, stop using it and check it for flavorings.

If your lips are dry while the rest of your face is oily, that is not a contradiction. The two surfaces run on different rules. The same idea runs through how you cleanse: if you use an oil cleanser, see how to oil cleanse properly and remember that lips need their own care afterward.

If cracking, swelling or scaling continues for weeks despite a plain balm, see a dermatologist.

This article is for general cosmetic information and is not medical advice. If you have a skin condition, speak with a dermatologist.