Causes of hair damage

The most common causes of damaged hair are:

• Excessive brushing: using a hard brush and brushing hair violently or when wet can damage it.
• Chemicals: chlorine from swimming pools, bleach, hair dyes and other salon treatments can damage the structure of your hair.
• Sun/heat exposure: exposure to the sun or excessive use of hairdryers and/or hair straighteners can dry out and damage hair.
• Poor diet: an unhealthy diet or a state of dehydration can affect the function of the hair follicles which disrupts hair growth.
• Disease or illness: there are several diseases or illnesses which can damage hair structure or cause thinning of the hair strands.
• Medication: certain medications especially those used in chemotherapy treatment damage hair structure and ultimately lead to hair loss.
• Male pattern baldness: a genetic condition in which changes within the male hormones or androgens damage the hair follicles which prevents them from producing more hair.

Following a good hair care routine can mitigate against some of these but if you do notice that you are losing an excessive amount of hair then seek medical attention.

Source : http://www.medic8.com/healthguide/hair-loss/hair-structure/causes-of-hair-damage.html

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