Sparser Hair
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A: It sounds as though you are describing breakage of the hair.
In addition, use a smoothing serum and a leave-in conditioner/detangler whenever you attempt to comb or brush through your hair. Combing the hair with a wide tooth comb for styling and detangling is best. If you must use a brush, don't use natural bristle brushes, but rather those with widely spaced plastic tines as these put less stress on the hair.
You may find that you need to trim of the thinnest portions of the hair length until you are comfortable with the density. However, if you are vigilant about keeping the hair well-conditioned and protecting it from damage from styling, you should see the growth of the hair proceed without (or at least with much less) thinning.
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See also:
Hair combing and brushing basics
How to choose the best hair brush for smooth and healthy hair