All About Head Lice

Facts about head lice, nit removal and nontoxic, chemical free head lice treatment

All About Head Lice

A little knowledge (about head lice) goes a long way.


Facts About Head Lice

  • Nits (the eggs of the head louse) are small yellowish-white, oval-shaped eggs that are "to the side of a hair shaft glued" at an angle
  • Nits must be laid by live lice. You cannot "catch nits"
  • A female louse lays 3-5 eggs a day. Once laid, it takes 7-10 days for a nit to hatch, and another 7-10 days for the female to mature and begin laying her own eggs
  • Head lice are clear in color when hatched, then quickly develop a reddish-brown color after feeding
  • Head lice are about the size of sesame seeds
  • Head lice have six legs equipped with claws to grasp the hair
  • Head lice are crawling insects. They can’t hop, jump, or fly
  • Head lice do not thrive on pets
  • Head lice are small, wingless insects which feed on human blood. They need human blood in order to survive
  • Head lice live for approximately 30 days on a host and a female louse may lay up to 100 nits (eggs)
  • Head lice off of their human hosts will starve. The NPA suggests that, in most cases, a head louse will not survive for more than 24 hours off of its human host

When is a Nit Not a Nit?

If you perceive or are told about ongoing problems with nits without ever seeing a louse, it may be confusion between nits versus common hair debris.  This debris is often referred to as DEC plugs and hair casts.


A Nit (Louse Egg) is a smooth, oval shaped structure which is attached to the side of the hair shaft ranging in color from off-white to brown and is slightly smaller than a sesame seed.  Nits are always the same shape; they are never irregular, fuzzy, or encircling the hair (although the glue that the louse produces may be seen to encircle tightly around the hair shaft).

Lice Treatment

The only treatment method that works 100% of the time is to manually remove all lice and all nits. Every member of the household should be checked and, if nits or lice are detected, treated to prevent re-infestation of anyone treated. Heat and chemical treatments do not kill all of the lice and nits.  Manual removal of all lice and nits is necessary to eliminate the infestation.

This fact sheet is for information only and is not meant to be used for self-diagnosis or as a substitute for consultation with a health care provider. If you have any questions about the disease described above or think that you may have a parasitic infection, consult a health care provider.

Information from the National Pediculosis Association™ at