No, braiding does not make hair grow longer. Hair growth occurs as the result of keratin, a protein, building up in the hair follicle. Keratin is transformed into the structures of the hair at this level. As more keratin builds up, hair is pushed up and out, resulting in growth.
Frequent braiding may actually cause hair breakage and hair loss. In traction alopecia, a type of baldness, hair ceases growing due to hair follicle trauma caused by persistent pulling and hairstyles that are too tight. Braids are often a major cause of traction alopecia and trauma-related hair loss. In some cases, the damage is permanent.