I have a thin hair from birth and I want thick hair? (Photo)

In my opinion, there exist many Hair products that will coat your hair to make it thicker.  In addition,we have found that by  using PRP Therapy some patients get a thickening of the hair shaft. This has been supported in numerous studies.
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An individual can not alter the thickness of hair they were given at birth. Castor oil and other treatments do not alter the thickness of a patient's original hair thickness.

People are born with fine, medium and coarse hair. Some people have very fine hair which is probably your case. You can use hair products that force water absorption in the hair shafts that thicken the hair, These products are available in your local pharmacy.