Humectants pull in and seal moisture in the hair. These hygroscopic compounds posses a chemical structure that attracts water from the atmosphere and binds it to various sites along the molecule.Moisture prevents the hair from drying out and keeps hair from breaking and forming split ends so you are able to keep more of your hair length and so you will end up with longer hair .
Here's a list of good humectants to look out for when buying your hair products
*1,2,6 hexanetriol Butylene
* Dipropylene glycol
* Triethylene glycol
*Erythritol Capryl glycol
*Phytantriol Hexanediol or -triol beeswax
* Jojoba oil
*Note that products that have a high quantity of petroleum and mineral oil.only act as sealants and prevents natural absorption of moisture unlike humectants.