Any kind of physical trauma—surgery, a car accident, or a severe illness, even the flu—can cause temporary hair loss. This can trigger a type of hair loss called telogen effluvium. Hair has a
programmed life cycle: a growth phase, rest phase and shedding phase. “When you have a really stressful event, it can shock the hair cycle, (pushing) more hair into the shedding phase. Hair loss
often becomes noticeable three-to-six months after the trauma.
Pregnancy is one example of the type of physical stress that can cause hair loss (that and hormones). Pregnancy-related hair loss is seen more commonly after your baby has been delivered rather
than actually during pregnancy. “Giving birth is pretty traumatic.
3. Lack of protein:
If you don't get enough protein in your diet, your body may ration protein by shutting down hair growth. This can happen about two to three months after a drop in protein intake.
Female-pattern hair loss, called androgenic or androgenetic alopecia, is basically the female version of male pattern baldness. “If you come from a family where women started to have hair loss at
a certain age, then you might be more prone to it,” Unlike men, women don't tend to have a receding hairline, instead their part may widen and they may have noticeable thinning of hair.
5. Female hormones:
Just as pregnancy hormone changes can cause hair loss, so can switching or going off birth-control pills. This can also cause telogen effluvium, and it may be more likely if you have a family
history of hair loss. The change in the hormonal balance that occurs at menopause may also have the same result
6. Emotional stress:
Emotional stress is less likely to cause hair loss than physical stress, but it can happen, for instance, in the case of divorce, after the death of a loved one, or while caring for an aging
parent. More often, though, emotional stress won't actually precipitate the hair loss. It will exacerbate a problem that's already there.