What are the causes of ridges in fingernails?

Vertical fingernail ridges are ones that start under the cuticle and extend to the end of the nail. These are not to be confused with horizontal nail ridges (running across the nail).

The actual source or cause of these vertical ridges is unknown, but heredity is thought to play a role. These ridges tend to become more prominent as we age. Vertical ridges do not pose a health problem - although sometimes the nail becomes weaker at these ridges and will split.

There is NO product on the market that can make these ridges go away. If you are getting splitting at these ridges then gently file the ends of your nails to help stop snagging. Also a penetrating nail conditioner not only helps maintain your nails, but it is an excellent way to lessen the chances of your nail cracking or breaking at these ridges.

Again, don't confuse vertical ridges with horizontal ridges. If your nails change color or have HORIZONTAL ridges you should see your doctor as this could indicate a health problem.

Vertical fingernail ridges are ones that start under the cuticle and extend to the end of the nail. These are not to be confused with horizontal nail ridges (running across the nail).

The actual source or cause of these vertical ridges is unknown, but heredity is thought to play a role. These ridges tend to become more prominent as we age. Vertical ridges do not pose a health problem - although sometimes the nail becomes weaker at these ridges and will split.

There is NO product on the market that can make these ridges go away. If you are getting splitting at these ridges then gently file the ends of your nails to help stop snagging. Also a penetrating nail conditioner not only helps maintain your nails, but it is an excellent way to lessen the chances of your nail cracking or breaking at these ridges.

Again, don't confuse vertical ridges with horizontal ridges. If your nails change color or have HORIZONTAL ridges you should see your doctor as this could indicate a health problem.

source:
http://www.flexinail.com/vertical-fingernail-ridges.php

One extremely common cause of ridges on fingernails is malnutrition or malabsorption. Many vitamin deficiencies cause ridges on fingernails, as the body's production of the materials in the nail is interrupted. Another cause of ridges on fingernails is lack of moisture. If your nails are ridged or cracked, massaging the nails or with a moisturizing cream or oil can be very beneficial, as can increasing the amount of water you drink.