What do lice feed on?

 

Lice are obligate parasites, meaning they depend on human blood to survive. They feed life cycle stages on the blood of their host by piercing the scalp with their specialized mouthparts. Once attached, they inject saliva to prevent blood from clotting and then draw blood through a small tube-like structure, feeding several times a day to stay nourished and hydrated.

Without access to blood, lice cannot survive for long, as they quickly dehydrate and lack the ability to store nutrients. This need for continuous blood intake keeps lice on or near the scalp, where they can access their host’s blood supply regularly. Lice do not feed on anything else besides human blood, which is why they are only found on human scalps and cannot thrive on other surfaces or animals.