Generally speaking, the entire nail bed should be a pinkish color in most individuals, although there is usually a lighter colored "moon shape" near the nail base. If your nails beds are not pink throughout, then I wonder if you might have something going on causing discoloration of the nail or separation of the nail from the nail bed, which can make the nail appear white.
There are many different nail diseases that can cause these changes, and you will need to make an appointment with either your primary care doctor
or a dermatologist
in order to figure out what is going on.
One very common cause of nail discoloration is frequent application of nail polish and nail polish remover, or chemicals used in manicures or with the application of false nails. The repeated exposure to these chemicals causes changes directly to the structure of the proteins that make up the nail, lead to color changes.
Also, a fungal infection of the nails will lead to whitish or yellowish color changes, as the fungus works its way under nail. Usually, there is also distortion or thickening of the nails as well.
Onycholysis, or separation of the nail from the nail bed, will also cause color changes. Onycholysis can sometimes be caused by repetitive trauma to the nails, or by various inflammatory problems in the body, and your doctor can investigate this possibility a bit more closely.