Why do people loss their hair? The most common cause of hair loss are; 1.Excessive sebum ( skin oil ) build-up at the bottom of the hair follicles. Excess sebum over time bonds with cholesterol. Combined, they form a plug which blocks air and blood access to the hair's reproductive part (bulb) at the hair's base at the bottom of the hair follicle, causing hair degradation and even infections. 2.The deposit from long time use the chemical shampoo and conditioner which block the follicle of the hair. Effective removal of this residue is the first necessary step towards healthy re-growth of you hair.