As hairs grow longer, they lose their thickness

The first picture is from Dr. Robert Haber’s magnified study of a hair scan of a single hair on one of Dr. Paul Cotterill’s female patients. It revealed that hair thickness and shape changes as the hair grows longer. The measurement scan below demonstrates the changes in this 21 cm long female single hair. Telogen is on the left (the end of the hair cycle) and the start of anagen on...

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