Smoking has been associated with hair loss due to several mechanisms, including:
- Vasoconstrictor action : Smoking can cause vasoconstriction, which reduces blood flow to the hair follicles, leading to hair loss
- DNA damage : Smoking can form DNA adducts, causing damage to hair follicles
- Oxidative stress and disequilibrium of antioxidant system : Smoking can increase oxidative stress, which can damage hair follicles
- Sustained microinflammation : Smoking can cause microinflammation, leading to perifollicular fibrosis and hair loss
- Reduced blood flow to hair follicles : Regular smoking damages blood vessels, reducing blood flow to hair follicles and delivering fewer nutrients to the scalp, which can accelerate hair loss
- Damaging existing hair : Smoking promotes the release of cytokines, proteins that can increase inflammation and cause scarring of the hair follicles, making hair more brittle and prone to falling out
- Low estrogen levels : Smoking can cause early onset of grey hair and make hair drier, increasing the chances of hair loss
Quitting smoking can help hair growth and reverse some of the damage caused by smoking
. Some people with thinning hair may achieve noticeable hair regrowth if the hair loss is caused by smoking
. However, it is not clear if hair loss caused by smoking can be completely undone
