Hair's main component is a protein called keratin. Water stretches and weakens keratin molecules, so hair is more fragile when wet.
Unfortunately, this is just when hair gets its roughest treatment: washing, drying and the application of all kinds of "care" products.
To minimize damage, wash hair only as needed. If you have naturally oily hair, that may be daily, but most guys can go longer. Overwashing can actually dull hair by stripping away protective oils.
Make your routine as gentle as possible. Use warm water, not hot water. Massage the scalp rather than scrubbing, and blot hair dry with a towel instead of firing up the blow dryer. Ease out tangles with a wide-toothed comb.
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