Causes

• There are many causes of thinning hair, some of which are diet, over processing of hair and genetics.
  
  

Genes

• When a genetic propensity for thinning hair is inherited, the individual receives a gene from one or both parents that causes the hair follicle to produce thinner hair and to grow the hair more slowly each subsequent growth cycle.
  
  

Gene-Hormone Interactions

• The genetic influence on hair loss can be affected by hormones, especially in men. Levels of testosterone and dihydrotestosterone, also known as DHT, interact with hair follicles to increase or decrease the degree of thinning, though these hormones do not cause or prevent it entirely.
  
  

Inheritance

• Male pattern baldness and female hair thinning can be inherited from either side of the family.
  
  

Treatments

• While thinning hair caused by genetics cannot be cured at this time, the interaction of genes and hormones can be treated. Many medications for thinning hair, including Rogaine and Propecia, work by acting on the hormones that mediate the genetic effects.