Source – NYU Langone
Hair loss, also known as alopecia, is a disorder caused by an interruption in the body’s cycle of hair production. Hair loss can occur anywhere on the body, but most commonly affects the scalp. Depending on the color of your hair…the scalp has anywhere from 100,000 to 140,000 hairs that cycle through phases of growing, resting, falling out, and regenerating. This cycle will continue throughout your life as a hair’s life expectancy is anywhere from 3-6 years.
Hair loss is most commonly linked to a person’s genetics, although many medical and behavioral conditions as well as medication and stress may interrupt the growth cycle and cause hair loss. We are going to highlight a few of the most common.
Androgenetic Alopecia
Androgenetic alopecia is the most common type of hair loss, affecting more than 50 million men and 30 million women in the United States. Commonly known as male pattern hair loss or female pattern hair loss, androgenetic alopecia is hereditary but can be managed with medication or surgery or treatments like laser hair therapy or PRP. There are two types of genetic hair loss:
Male Pattern Hair Loss
In men, hair loss can begin any time after puberty and progress over the course of years or decades. It starts above the temples and continues around the perimeter and the top of the head, often leaving a ring of hair along the bottom of the scalp. Many men with male pattern hair loss eventually become bald.
Female Pattern Hair Loss
In women, hair slowly thins all over the scalp, but the hairline usually doesn’t recede. Many women experience this type of hair loss as a natural part of aging, although hair loss may begin any time after puberty. Female pattern hair loss can cause hair to thin dramatically, but only rarely does it lead to baldness.
Telogen Effluvium
Telogen effluvium occurs when large numbers of follicles on the scalp enter the resting phase of the hair growth cycle, called the telogen phase, but the next growth phase doesn’t begin. This causes hair to fall out all over the scalp without new hair growth.
Telogen effluvium does not generally lead to complete baldness, although you may lose 300 to 500 hairs per day, and hair may appear thin, especially at the crown and temples.
A medical event or condition, such as a thyroid imbalance, childbirth, surgery, or a fever, typically triggers this type of hair loss. Telogen effluvium may also occur as a result of a vitamin or mineral deficiency—iron deficiency is a common cause of hair loss in women—or the use of certain medications, such as isotretinoin, prescribed for acne, or warfarin, a blood thinner. Starting or stopping oral contraceptives (birth control pills) may also cause this type of hair loss.
Telogen effluvium usually begins three months after a medical event. If the triggering event is temporary—for example, if you recover from an illness or stop taking the medication causing the hair loss—your hair may grow back after six months. Telogen effluvium is considered chronic if hair loss lasts longer than six months.
For reasons that are unclear to doctors, this type of hair loss may last for years in some people. If hair doesn’t regrow on its own, our dermatologists can offer medication that can help.
Alopecia Areata
Alopecia areata is an autoimmune condition, which means the body’s immune system attacks healthy tissues, including the hair follicles. This causes hair to fall out and prevents new hair from growing.
This condition can affect adults and children, and hair loss can begin suddenly and without warning. Hair from the scalp typically falls out in small patches and is not painful. Hair in other parts of the body, including the eyebrows and eyelashes, may also fall out. Over time, this disease may lead to alopecia totalis, or complete hair loss.
Trichotillomania
People with trichotillomania pull their hair out and find it difficult to stop. This results in hair loss on the scalp or elsewhere on the body. Hair often returns if the behavior is stopped, but hair loss can be permanent if the pulling continues for many years.
The best treatment for this condition may be psychotherapy, which might include talking with a counselor about causes of stress and why you feel the urge to pull your hair.
Traction Alopecia
Some hairstyles, including tight ponytails and braids, pull hair away from the scalp with such force that hair strands are damaged and fall out. Unless the hairstyle is changed, traction alopecia may lead to thinning hair or bald spots. Most of the time, hair regrows after you alter the hairstyle.
If you are experiencing hair loss, seek the help of a professional as soon as possible. It is much easier to hold on to what you have than regrow what you have lost.