We lose about 100 strands a day, which is natural. What is not natural is heavy shedding or hair falling out in clumps. “It is normal to have hair loss as we age due to the weakening follicles,” says Kane, “but sudden loss could be caused by a vitamin deficiency and I always recommend seeing a doctor.”
Curtis says that hair loss can be indicative of a few issues. “A common condition, called telogen effluvium, is a fancy medical term for sudden shedding,” she says. It occurs when the number of hair follicles producing hair suddenly drops, causing diffuse thinning, often more so on top of the scalp than on the back or sides. “The classic cause is after a woman has a baby,” she says. “But it can also occur after any dramatic change or shock, such as an illness, surgery or crash diet. The body perceives crash dieting as famine and goes into emergency shut-down mode, which is not good for your hair.”
What is good is that hair loss from these situations is reversible. Some medications, including those for acne, beta blockers, anticoagulants, arthritis, depression, gout, high blood pressure, heart problems, steroids or birth control pills can cause hair loss, as can a vitamin D deficiency. Some illnesses and diseases, such as severe infection or flu, high fever, cancer or thyroid disease, can cause hair loss, but is usually temporary. Patchy hair loss, called alopecia areata, or spot baldness, is an autoimmune disease which can also cause eyebrows and eyelashes to fall out. “It’s the hair version of vitiligo, where the immune system attacks pigment cells,” Curtis explains, noting the reason is unknown.
Excessive styling, tight ponytails, braids and other hairstyles that pull on the hair can also cause hair to fall out. If you tenderly tend your tresses, however, see your doctor for testing for anemia, thyroid or autoimmune diseases.