Head lice can be hard to get rid of. Even worse are their eggs, commonly called nits. Female lice lay eggs directly onto strands of hair, and they cement them in place with a glue-like substance, making them hard to get rid of.
In fact, the eggs are glued down so strongly that they will stay in place even after the lice themselves have been killed.
Some shampoos and conditioners that contain chemicals or special oils are marketed as nit-removal products, but new research finds plain old hair conditioner works just as well.
In a study just published in the Journal of Medical Entomology, scientists from Belgium gathered 605 hairs from six different children. Each hair had a single nit attached to it. Approximately 14% of the eggshells contained a dead egg, while the rest were empty.
They then tried to remove the eggs and tested the amount of force needed to do so. They found that nits on the hairs that were left completely untreated were the most difficult to remove. Eggs on hairs that had been soaked in deionized water were much easier to remove, as were the eggs on hairs that had been treated with ordinary hair conditioner and with products specifically marketed for the purpose of nit removal.
No significant difference
However, they found no significant differences between the ordinary conditioners and the special nit-removal products. In all cases, less force was required to remove the nits after the hair had been treated, but the effectiveness of the products was essentially the same.
"There were no significant differences in measured forces between the ordinary conditioner and the commercial nit removal product," the authors write. "The commercial nit removal products tested in the current study do not seem to have an additional effect."
The authors hypothesize that the deionized water was effective because it acts as a lubricant, so less friction is needed to remove the nits from the hairs. The same goes for the conditioners.
"Treatment with conditioner reduces the coefficient of friction of undamaged and damaged hair," they write. "As a consequence, conditioners will facilitate nit removal."