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Dr Edward Ball, a leading UK hair transplant surgeon from specialist London centre The Maitland Clinic, said the common causes of hair loss are hormonal and genetic.
There are many causes of hair loss: stress, nutrient deficiency and illness. Regular exercise and sound sleep can restore the hair.
Apart from all these, testosterone derivative dihydrotestosterone (DHT) can results in the hair cycle getting shorter and the hair follicles shrinking until they eventually disappear.
Some people are genetically more sensitive to the effects of DHT, which leads to rapid hair loss. Hair loss caused by DHT and a genetic disposition may required surgical treatments.