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Hair Loss Causes


Some Loss is Normal

All hairs are shed at the end of their growth cycle, so some degree of hair loss is normal. If you have excessive hair loss, it makes sense to first understand the possible causes.

There are many possible causes of hair loss, however most hair loss is normal, and part of each person’s genetic program. All of the following hair loss causes are explained in greater detail in this section.

Diseases that Cause Hair Loss

While inherited “Pattern Hair Loss” is the cause of most hair thinning, a wide range of disease conditions can also cause hair loss, including disorders such as alopecia areata, lupus erythematosus, thyroid disease, iron deficiencies, hormone imbalances, infections, and drug reactions. Some hair growth disorders cause temporary hair loss, while others can result in scarring or permanent hair loss. As a Board Certified Dermatologist, Dr. Panagatacos is an expert at diagnosing and treating these types of conditions.

Cause of 95% of all Hair Loss

Androgenetic alopecia is the scientific name for the genetic predisposition in both men and women for pattern baldness or pattern hair loss. Androgenetic alopecia is the cause of over 95% of all pattern hair loss, including baldness in men and thinning hair in women. Pattern hair loss occurs in somewhat predictable stages, and is relentlessly progressive. This means that those with pattern hair loss will, if they live long enough, eventually progress from the early stages of loss to the advanced stages. We all suffer hair loss; some people just arrive at the advance stages of hair loss sooner than others. Studies have shown that pattern loss is increasingly evident and advanced as people age.

Patchy Hair Loss

Alopecia areata is an immune system disorder which causes hair follicles to stop producing hairs. Approximately 2% of all people experience an episode of alopecia areata at some point in their lives. Sudden loss of hair from small patches on the head are a common symptom. In the vast majority of cases the condition is temporary and goes away all by itself withing 6-7 months, and hair growth in the bald patch resumes. About 10% of those who have an episode of alopecia areata experience longer-term hair loss, or new patches of hair loss as old patches resume hair growth.

Advanced forms of the disorder include alopecia totalis, where all hair on the head is lost, and alopecia universalis, which results in the absence of all body hair. There is no sure cure for this condition, although some treatments help to control the episodes. Because the condition most often goes away all by itself, there is a great deal of confusion about treatment effectiveness. Some “miracle cure” hair loss treatments use subjects with alopecia areata to “prove” that their treatment works. When hair growth resumes, the “treatment” is given credit.

Hair Pulling

Traction alopecia is the loss of hair from constant pulling, often the result of tightly braided hair styles.

Delayed Shedding from Stress


This condition is a very common cause of large amounts of hair falling out. Telogen effluvium is a slowing of new hair growth resulting from sudden severe emotional, physical, or hormonal stress, followed after a delay of about 2 months by the shedding of hair, sometimes in alarming amounts. Stressful events include death of a loved one, divorce or personal relationship break-up, job loss, termination of pregnancy (including giving birth), very high fever, major surgery, and tranplantation of hair follicles.

Normally about 5-10% of your scalp hair follicles are resting at any one time. With telogen effluvium, the stressful event induces a higher proportion of hair follicles to enter the resting stage all at the same time. A few months later, after the stressful event, all of the now-resting follicles begin to shed their hairs at about the same time. Because the stressful event happened months ago, most people do not connect it with their hair loss. It is a temporary condition, and new hairs begin growing within a few months, and the normal pattern of hair growth resumes so that with the next cycle of hair growth all of the follicles do not “rest” at the same time.

Sudden Hair Loss


This is a very rare condition, except as a side effect to certain forms of cancer treatment. The condition essentially is the poisoning of certain hair follicle cells that divide very rapidly to grow the hair shaft. Anagen effluvium is the sudden loss of growing hairs as a result of chemicals or radiation.

Unlike TELOGEN EFFLUVIUM, there is no significant delay with ANAGEN EFFLUVIUM: lots of hairs fall out all at once very soon after the toxic event. Cancer treatments such as chemotherapy and radiation therapy halt the growth phase of hair follicles, because they are designed to poison rapidly dividing cells, which is what exactly what cancerous cells do. Unfortunately, hair follicle cells are among the most rapidly dividing cells that naturally occur in the body. The result is the sudden shedding of hair. Some medications can also cause hair loss as a side effect, for a variety of reasons. Most cases of anagen effluvium are temporary, and a few months after the chemicals, radiation, or medication is discontinued, the hair follicles begin to grow new hairs again.

Broken Hairs

Hair shaft breakage is when part of a hair breaks off, but the growing end remains in the follicle and continues to grow. Hair shaft breakage results in thinner hair, and can be caused by excessive styling, chemicals, sun, and chlorine in swimming pools.

Nutritional Deficiencies

Nutritional deficiencies are rarely a cause of hair loss. In rare cases certain nutritional deficiencies can cause weak hair shafts that tend to beak off.

Other Hair Loss Causes

Certain chronic Illnesses can result in hair loss. Hormone-related irregularities can include hair loss among other symptoms. Skin Infections can result in hair loss. Trauma such as burns and injury to hair follicles, can cause permanent hair loss.

Read Hair Loss Answers

Hair Loss Answers” is the most comprehensive and authoritative lay person’s guide to hair loss treatments on the market today. Concerned patients need a source for answers to hair loss questions, and expert advice on which solutions really work. “Hair Loss Answers” was written to address that need.


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