If you haven't already, click here to see part 1 - Henna: How does it work?
Does Henna loosen curls or thicken hair?
There are many users who state this but it has not yet been scientifically reported. The interesting bit of information though is that hair dyed with Henna actually becomes measurably heavier (International Journal of Cosmetic Science, pg153-174, 1982). This can be expected as Lawsone binds to the hair cuticle, therefore, the weight increase is related to how much lawsone has been deposited on the hair strands. I guess in theory, this increased weight on the hair shaft may lead the curl to look 'loosened'. This is different from texturisers which actually break bonds in the hair. Given the weight effect, it is safe to assume that the binding of lawsone to the cuticle may indeed lead to thicker hair. However what is not known is how much thicker the hair becomes or whether this thickening is beneficial.
Does Henna make hair shed less?
No is the simple answer. Hair shedding is programmed from the root/bulb of the hair. Henna doesn’t have an effect there. However if someone is talking about absolute hair shedding (meaning actual shed hairs plus strands that normally get broken during manipulation of hair) then it is possible to make this observation. That said, this has not been shown scientifically.
Does Henna make hair stronger?
Again, this has not been scientifically reported which lends this question to theories. There are two contrasting observations with Henna. First, the use of Henna may lead to dry hair. Dry hair =Less elastic hair = Breakage=Weak Hair? Second the use of Henna may increase hair thickness. Greater thickness = resistance to breakage = Stronger hair?
Confused? Well until someone strength tests hair treated with Henna we will never know. On balance from this research, I would recommend paying more attention to conditioning hair if you do choose to use Henna so as to restore and maintain a good moisture balance.
Click here to go to part 3: Henna: A Serious Note