Hair fall after an illness is usually not what people fear

Sudden, diffuse hair shedding six to twelve weeks after a fever, surgery, childbirth or significant weight loss is usually telogen effluvium.

It looks alarming — handfuls in the shower — but the follicles are intact and it is self-limiting in most cases.

What helps: treating the underlying cause, checking ferritin, thyroid and vitamin D, and being patient for three to six months.

What does not: switching shampoos weekly, or starting several supplements at once so that nothing can be attributed.

Patterned thinning at the crown or hairline is a different problem and does need assessment.