|MadSci Network: Biochemistry|
Shama, Hair is made of a protein called keratin that coils up into very dense structures that are bound so tightly together that they are very impermeable to water. Actually, your outer layer of skin cells are dead epidermal cells that have very high amounts of keratin and lipid in them such that they form a waterproof layer around your body. My point is that keratin is not a water-loving protein, but rather a protein that tends to exclude water from its very high-strength form. So imagine the converse: the strength of hair is due to the strength of the structure of keratin, a structure that doesn't like water. If you add a huge amount of water to hair, this could weaken the keratin structure, which would weaken the hair. This is the way I would explain this. However, I personally have never noticed that my hair is more fragile when it is wet, so I am not sure that it really is. Chris
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