Skip the sauna before your manicure: how humidity affects your nails
Nails absorb water quickly and swell. If gel is applied to a nail that is still swollen from a hot bath, steam or sauna, the nail shrinks back as it dries, but the cured gel can't. That breaks the bond and causes lifting. Keep your hands dry for a few hours before your appointment.
I often get asked if it's okay to go to a sauna or steam room, or take a hot bath, right before a manicure. A spa day sounds relaxing, but soaking your hands before gel is one of the main reasons gel starts lifting early. This is what I took from Douglas Schoon's book Nail Structure and Product Chemistry.
Nails act like sponges
The natural nail plate is hygroscopic. That means it takes up and gives off water very quickly. When your hands are in high humidity, hot water or steam, the layers of keratin absorb water and expand. The nail plate actually becomes thicker and wider as it fills with moisture.
A healthy nail plate normally holds about 15 to 18 percent water. After soaking, that can double to 25 to 30 percent, and the nail gets thicker and wider. Substantial absorption starts within about a minute. As the nail dries, it shrinks back to its original size and shape.
Milady's textbook agrees that the nail plate is porous to water, and says its water content follows the humidity of the surrounding air.
Why gel on a wet nail lifts
If gel polish or builder gel goes on while the nail is swollen with water, the coating is sitting on a surface that is still changing shape. Over the next day or two the nail dries out and shrinks back to its normal size. Cured gel is rigid and can't shrink with it. The stress at the border between the two breaks the bond, and you get small gaps and lifting at the free edge or along the sidewalls.
Water also gets in the way of adhesion itself. Gel holds on by gripping the tiny irregularities in the top layer of the nail plate, and a nail that is wet cannot be gripped as well as a dry one.
How I keep your nails dry in my studio
I work waterless, with the European/Russian technique, so the nail stays in its normal dry state:
- I never soak your fingers in a bowl of water during cuticle care.
- I use a dehydrator to remove surface moisture and natural oils without damaging the keratin.
- I ask you to keep your hands away from heavy steam, saunas and hot baths for at least 2 to 3 hours before your appointment.
When the nail is dry and at its natural size, the gel bonds to it properly and your manicure lasts longer.
The effect is different for every client. Thick, firm nails are often hardly affected, while thin or weak nails are affected much more.
Can I take a hot bath or go to a sauna before my manicure?
It's better not to. Steam and hot water make the nail swell. Please keep your hands out of heavy steam, saunas and hot baths for at least 2 to 3 hours before your appointment.
Why does gel lift when the nail was wet?
A wet nail is slightly larger. When it dries it shrinks back, but cured gel is rigid and can't shrink with it, so the bond breaks and small gaps appear.
Why don't you soak my fingers during a manicure?
Soaking makes the nail plate absorb water and swell. A waterless manicure keeps the nail dry and at its natural size, so the gel adheres better.
By Volha Zhybuliova
Sources: Douglas D. Schoon, Nail Structure and Product Chemistry (Milady); Doug Schoon, Water vs. Waterless Manicures (Nail Knowledge); Milady Standard Nail Technology, 7th ed. (Cengage Learning), Ch. 8, Nail Structure and Growth