A:

Poliosis is white hair from loss of pigment. This can happen in the eyelashes, eyebrows, scalp hair, or any other areas with hair.

There are a few causes for poliosis:

• Inherited defects.
• Autoimmune conditions. Here, the body's immune cells, for unknown reasons, attack pigment cells.
• Damage to hair follicles from radiation therapy or certain medical conditions, such as skin cancer.

Otherwise healthy people can get poliosis from minor genetic defects. In some cases, poliosis can be linked with more serious defects such as deafness and mental retardation.

An example of an autoimmune condition that causes hairs to turn white is vitiligo. In this condition, immune cells attack skin pigment, leaving patches of white skin. Hairs in the affected areas may also lose pigment.

In many cases, poliosis isn't medically serious. But in others, there may be underlying medical problems. It's a good idea to see your doctor.

Since you mention white eyelashes, ask your doctor whether you should have an exam by an eye specialist. Although unlikely, an ophthalmologist could check for any associated eye problems.