Gel manicures are known for shining brighter and lasting longer than a regular manicure, lasting as long as two weeks without a crack.

But can the special process that gives your nails their patent leather gleam also be harmful to your health?

The gel manicure process requires four or five coats of polish, with each layer followed by a finish under a UV light, a similar light to those used in tanning beds, only far weaker.

Safer Mani-Pedis: Steps You Can Take

Some dermatologists warn the typical 5-10-minute exposure to the light during a gel manicure could be harmful.  A 2009 article in the Archives of Dermatology concluded that "further investigation" was warranted to see if the UV nail lamps can cause cancer.

A nail-industry sponsored study conducted at the Lighting Sciences Inc., an independent lab in Scottsdale, Ariz., found that getting a gel manicure every two weeks is equivalent to spending an extra two minutes in the sun every day.

Just as dermatologists have long advocated wearing sunscreen on a daily basis, they now also recommend wearing sunscreen on your hands when you go for a gel manicure.

Nail drying lights emit UV-A rays and not all sunscreens protect against those.  That's why dermatologists say you should be sure to apply a "broad spectrum" sunscreen that protects against both UV-A and UV-B rays before any manicure.

The American Academy of Dermatology (AAD) says sunscreens with the following ingredients provide broad spectrum protection:

Avobenzone

Cinoxate

Ecamsule

Menthyl anthranilate

Octyl methoxycinnamate

Octyl salicylate

Oxybenzone

Sulisobenzone

Zinc oxide

Titanium dioxide.

Here are 10 warning signs to look for when getting a gel manicure -or any manicure, according to the Professional Beauty Association.

1. Your salon uses bottles in unmarked containers.
2. The products smell unusually strong or have a strange odor.
3. Your skin is abraded or cut during the procedure.
4. The instruments used on you are not sterilized.
5. Your skin or nails hurt during or after the nail service.
6. The technician cannot tell you what is in the products.
7. The salon is not clean.
8. Licenses for the salon and individual operators are not visibly posted
9. You see swelling, redness or other signs of infection around your nails.
10. You are not asked to wash your hand and you do not see the nail technician wash his/her own hands before the nail service.