Hair Loss

Why Do We Lose Hair?

Most people routinely lose between 70 and 150 hairs from their scalp each day, mainly through washing, brushing, and combing.

Scalp hair starts to thin when more hairs are lost through normal shedding than the scalp is able to renew. About 40% of the density of scalp hair has to be lost before thinning of the hair becomes noticeable.

Hair loss can be caused by:

• Heredity. Most balding is caused by a genetic predisposition – in other words, it’s part of a person’s genetic makeup. This is called male pattern baldness, or hereditary balding or thinning. It is the most common cause of thinning hair.
• Illness, certain physical conditions, or their treatments. This can include high fever, thyroid disease, childbirth, inadequate protein in the diet, iron deficiency, cancer treatments, the use of certain medications, and other causes.

Hair may be lost in two ways:

• In patchy hair loss, well-defined areas of hair are lost while the remaining scalp retains a good covering of hair.
• In generalized hair loss, there is a uniform thinning over the entire scalp with no areas of normal hair growth.

The medical term for hair loss is alopecia. There are different classifications of alopecia:

• Alopecia areata is a disease in which well-defined bald patches occur. It usually clears completely within 6 to 12 months without treatment.
• Alopecia totalis is an uncommon condition in which all hair on the scalp is lost. The cause is unknown, and the baldness is usually permanent.
• Alopecia universalis is a total loss of hair on all parts of the body.
• Androgenetic alopecia is balding caused by heredity. It can affect both men and women, although women with this inherited tendency do not become totally bald. The condition can start in a person’s teens, twenties, or thirties.

The Structure Of Hair

Every hair grows within a hair follicle, which is a tiny tube of cells close to the surface of the skin. Each hair has a root and a shaft within this follicle.

If you pluck a hair and hold it up to the light, the root will appear as a bulbous white swelling at the deep end. The root lies between 2 and 4 millimeters (about a tenth of an inch) under the skin surface. Its purpose is to produce the actual hair, which is known technically as the hair shaft.

The hair shaft contains no living tissue. It consists of protein material twisted into a very fine rope-like arrangement. It is this part of the structure that we think of in everyday terms as “hair.”

Each hair has:

• A sebaceous gland, which provides fats and greases to the hair
• An erector muscle, which is responsible for lifting the hair off the surface of the skin at times of stress or to conserve warmth

The hair root does not grow continuously, but rather in a cycle of stops and starts.

• There is an initial period of active growth that lasts about three years.
• As the period of growth ends, the deepest part of the hair follicle wastes away.
• The hair root then enters a resting period of about 90 days, during which no further hair is produced by the resting root.
• At the end of this phase, the hair falls out and a new hair is produced.

Human hairs are randomly distributed all over the scalp in terms of their growth pattern, so that at any one time, some hairs will be actively growing while others are resting. Only those hairs ending their resting phase are lost each day.

There is tremendous variation in the number of hairs that people shed each day, depending on the number of scalp hairs and the length of the growth cycle. As people age, their rate of new hair growth slows down, resulting in a gradual thinning.

What Causes Hair Loss?

The causes of hair loss vary, depending on the type:

• Generalized hair loss
• Patchy hair loss
• Balding in men

Generalized Hair Loss

Abnormal hair loss may occur:

• Following certain illnesses and infections
• After prolonged vitamin deficiencies, or a deficiency of protein or iron
• Because of a disorder of the thyroid gland, in which there is too little thyroid hormone circulating throughout the body, causing inadequate stimulation of activity in body cells
• As a side effect of medication or medical treatment (for example, chemotherapy or radiation therapy for cancer)
• Following exposure to some toxic substances such as thallium (thallium sulfate is widely used as a rat poison)

In these cases, the hair loss is not immediately obvious. Although growth stops at once in the hair follicles, the dead hairs are not shed from the scalp until about three months later, when they fall out from their roots.

Major illness, injury, high fever, major surgery, severe bleeding, and possibly even severe emotional stress may cause sufficient physical upset to shock the actively growing hair roots into the resting phase, possibly to conserve energy that will be needed by the body for physical repair.

The roots remain securely anchored for three months, so there is no immediate apparent effect on hair growth following the illness or injury. But three months later, the hair sheds, and this may continue for some weeks.

Since this process does not damage the hair roots, they start to regrow – but it might be several weeks or months before new hair becomes apparent. Scalp hair grows at a rate of about 1 centimeter (around half an inch) per month.

Patchy Hair Loss

Patchy hair loss can be caused by:

• Ringworm. Small patches of hair loss associated with dandruff-like scaling of the scalp and stubby, broken hair shafts within the bald area is typical of scalp ringworm. It occurs in children and is highly contagious, but it is not a serious threat to health. Once the diagnosis is made, the condition is easily treated with anti-ringworm treatment.
• Alopecia areata. This condition involves patchy hair loss with normal underlying skin; the cause is unknown. As the hair in one patch starts to grow again, another bald patch may develop elsewhere. No cure for this condition is known, but it usually clears up by itself in six months to a year.

Balding In Men

Balding is a normal process that develops to some degree in all men. It is influenced by male sex hormones, called androgens. Hormones are chemical messengers produced by the body that stimulates activity by organs or tissues elsewhere in the body.

There also is a strong inherited factor in balding. The trait can be inherited from either the mother’s or the father’s side of the family. It can affect both men and women, although women with this inherited tendency do not become completely bald.

The process of balding is due to progressive miniaturization of individual hair follicles, which become smaller and have a shorter growth cycle. The hairs consequently become smaller and narrower. The number of hair follicles remains the same, however. There is the same number of hair follicles in the scalp of a bald man as in the scalp of a man with a full head of hair.

The very first signs of the effects of androgens on scalp hair growth occur soon after puberty, which is the stage in the human life when the reproductive organs reach maturity. In boys, puberty occurs around age 13. After puberty, the front hairline above the temples may recede. In some men, this may be as far as the balding process will develop.

There is tremendous variation in the extent to which individuals may lose hair.

• Some men experience a recession of the front hairline above the temples while retaining hair in the middle, which creates an “M” shape in the hairline above the temples and forehead.
• Some lose hair on the center of the scalp, which produces a “bald spot” surrounded by hair.
• Others have the recession at the front of their scalp join up with this area to create a larger balding area.
• Some develop uniform thinning of the hair over the top of the scalp, with no discernible pattern; this usually progresses to complete baldness.

Are There Ways To Restore Hair?

Generalized hair loss – resulting from certain illnesses and infections, vitamin deficiencies, as a side effect of medication or medical treatment, and following exposure to toxic substances – is usually temporary. Because these processes do not damage the hair roots, hair will regrow in the vast majority of people.

Patchy hair loss caused by ringworm is easily reversed with anti-ringworm treatment. Patchy hair loss caused by alopecia areata cannot be cured, although the condition usually clears completely by itself within six months to a year.

Balding in men is normal, and no treatment is required if the person is comfortable with the appearance. Treatments for this condition are designed to reverse the normal and natural course of events. Ways to restore hair in men who are balding include:

• Camouflage techniques
• Plastic surgery techniques
• Drug treatments

Camouflage Techniques For Hair Loss

Techniques for camouflaging (hiding) the hair loss include:

• Toupees and hairpieces
• Hair weaving

Toupees And Hairpieces

Toupees and hairpieces may be complete or partial, and they may be made of artificial fiber or natural hair. The overall cosmetic effect is dependent on the skill with which the color, thickness, and hair length are matched.

The goal is for the added hair to look natural, and this is difficult if the transformation is made all at once. A useful strategy it is use two or three hairpieces over the course of a few months, each slightly thicker than the previous one.

Hairpieces frequently look unnatural because they contain too much hair. A good hairdresser may be very helpful with careful positioning, trimming, and securely fixing of the hairpiece.

Hair Weaving

This technique allows artificial or natural hair to be anchored onto, or braided into, the remaining natural hair. Some of the natural hair is woven or braided together to act as an anchor onto which either artificial or natural hair tufts are sewn, woven, knitted, or glued.

The effect is semi-permanent, and the hair can be trimmed and styled to blend in with the natural hair. However, as the natural hair grows, the anchoring needs to be tightened every six to eight weeks, which can be expensive. Also, vigorous washing may loosen the new hair.

Plastic Surgery Techniques For Hair Loss

Plastic surgery can help to lessen the visible effects of baldness. Techniques include:

• Hair transplantation
• Scalp flap transfer
• Skin expansion
• Serial excision

Hair Transplantation

This is the traditional method of resurfacing bald areas of scalp with hair. Plugs of bald scalp are removed and then filled with plugs of scalp containing several hair roots taken from hair-bearing areas. These grafts hear into their new locations, and the hair follicles eventually grow.

The number of grafts required and the length of a treatment session will vary, depending on the degree of baldness. Several operations may be required, and the procedure can be expensive. The technique does leave many small scars on the donor sites, but these are not usually apparent.

Scalp Flap Transfer

This technique is based on the fact that the sides of the scalp (above the ears) and the back of the scalp usually remain hair-bearing. A long thin “flap” of hair-bearing scalp is removed and replaced across a bald patch to create a dense band of normal hair growth. Parts of the bald scalp may be removed as part of the procedure. The donor site is closed by stretching the adjacent scalp.

This technique can replace hair across a large area of bald scalp. The thick hair growth looks normal. The very narrow scars are easily hidden among the hair.

Skin Expansion

In this technique, one or more inflatable bags are inserted in pockets under areas of hair-bearing scalp adjacent to the bald patch. These bags, or expanders, are connected to valves that are also implanted under the skin. After the scalp has healed following the surgery, saline is injected into the valves, causing the expanders to gradually enlarge and stretch the overlying hairy scalp.

After a number of injections, over a period of some weeks or months, the expanders are so large that they have stretched out the hairy scalp to a greatly increased area. At a second operation, the bald scalp can be removed and the expanded hair scalp can be stretched to take its place.

This technique can produce excellent results, but during the interim period, while the expanders are getting bigger, the appearance can be bizarre. In addition, any procedure involving implanted foreign material may be complicated by infection.

Serial Excision

In this technique, as much of the bald area as possible is surgically removed in the first operation. The adjacent hair-bearing areas of scalp are pulled in close to the bald area, accepting the fact that some bald scalp will remain. This process is then repeated one or more times at a later date, so that the bald area is eventually removed.

Drug Treatments For Hair Loss

Two medications have been approved for the treatment of hair loss:

• Minoxidil (Rogaine)
• Finasteride (Propecia, Proscar)

Both of these medications also can be used preventively to help keep hair loss from happening.

Minoxidil (Rogaine)

Minoxidil (sold under the brand name Rogaine and also available generically) is applied to the scalp to stimulate hair growth in adult men and women. Medication applied to the body is called “topical” medication.

In the U.S., minoxidil is available without a prescription. The exact way in which this medicine works is not known.

Side effects of minoxidil are rare and include:

• Itching or skin rash on the scalp
• Headaches
• Dizzy spells
• Irregular heartbeat or chest pains
• Decreased sexual ability or desire

Minoxidil does not work for everyone, and it does have some limitations:

• Minoxidil may help hair to grow in 10% to 20% of the population, and in 90% it may slow the loss of hair.
• If hair growth is going to occur with the use of minoxidil, it usually occurs after the medicine has been used for several months.
• When the use of minoxidil is discontinued, hair loss will recur.
• If minoxidil is not allowed to completely dry (which may take two to four hours), it may stain clothing, hats, and bed linen.

Finasteride (Propecia, Proscar)

Finasteride (sold under the brand names of Propecia or Proscar) is a medication taken by mouth. It belongs to a group of medicines called enzyme inhibitors. It is primarily used to treat urinary problems cause by enlargement of the prostate in men (benign prostatic hyperplasia, or BPH).

Finasteride has been found to stimulate hair growth in some men. Women, however, should not take finasteride. The medication is available only with a doctor’s prescription. In clinical studies, it stopped hair loss in 83% of men.

If hair growth is going to occur with the use of finasteride, it usually will happen after the medicine has been used for about three months. The effect lasts only as long as the medicine is taken; new hair is lost within a year after finasteride treatment is stopped.

Side effects of finasteride are uncommon and include:

• Breast enlargement and tenderness
• Skin rash
• Swelling of lips
• Abdominal pain
• Back pain
• Decreased sex drive
• Decreased amount of semen that is ejaculated during orgasm (this should not affect sexual performance, however)
• Diarrhea
• Dizziness and headaches
• Impotence (inability to achieve or maintain an erection)

Hair Loss In Women

A gradual thinning of the hair frequently occurs in women as they grow older. But it differs from the hair loss experienced in men, because complete hair loss in women is hardly ever seen.

Hormones play a role in hair loss in women:

• Thinning of scalp hair occurs in as many as one in eight women before menopause (the end of menstrual periods in women), and in more than one in three women after it.
• Scalp hair normally thickens and becomes more lustrous during pregnancy, but childbirth triggers the switching of active hair roots to the resting phase. Hair loss therefore occurs about three months later.

The range of possible remedies for the treatment of thinning hair in women is similar to those available for men. In women, however, hair loss most often involves widespread thinning rather than the development of bald patches, so that careful styling, along with the use of hair preparations to “thicken” the remaining hair, may be all that is needed.

Can Hair Loss Be Prevented?

There are many reasons for the loss of hair. Prompt treatment of health conditions that can lead to hair loss, such as thyroid disorders, can help prevent the hair loss from occurring.

The most common cause of hair loss is balding in men. Until recently, male pattern baldness could not be prevented. Today, the two medications used to regrow hair can also be used to prevent hair loss:

• Minoxidil (Rogaine), which is applied to the scalp, may slow the loss of hair in 90% of men. Treatment is expensive, however – the cost is about $600 a year for the recommended use of twice daily. Any hair loss that is slowed by the medication will resume when its use is discontinued.
• Finasteride (Propecia, Proscar), is a hair-promoting drug taken by mouth that is approved for use in men only. In clinical studies, it stopped hair loss in 83% of men. However, the medication can have significant side effects.

Hair Loss: Frequently Asked Questions

Here are some frequently asked questions related to hair loss.

Q: What should I do if I think I’m losing more hair than normal?

A: If you notice you are shedding hair excessively after combing or brushing, or if your hair is becoming thinner, you should consult with your primary care provider or a dermatologist (a physician who specializes in treating skin and hair problems). A doctor can determine if disease is present and whether or not the hair loss will respond to medical treatment.

Q: Who is qualified to perform hair restoration surgery?

A: In order to ensure maximum safety and the best-looking results, choose a board-certified dermatologic surgeon who is an expert in the causes and treatment of hair loss. Since the success of the procedure greatly relies on the physician’s skill and creativity, it’s important to see a dermatologic surgeon with training and experience. Dermatologic surgeons invented hair transplant procedures in the 1950s.

Q: Is it safe to have surgery at hair treatment clinics?

A: Many hair treatment clinics also offer surgery for baldness. But it is essential that anyone interested should be fully satisfied about the quality of the care offered, before agreeing to a costly series of operations that do involve some risk.

Q: I heard that balding is inherited only through the mother’s side of the family. Is this true?

A: The tendency toward balding can be inherited from either the mother’s or the father’s side of the family. It can affect both men and women, although women with this inherited tendency do not become completely bald. Most balding is hereditary. Two out of every three men will eventually experience some form of balding.

Hair Loss: Putting It All Together

Here is a summary of the important facts and information related to hair loss.

• Most people routinely lose between 70 and 150 hairs from their scalp each day.
• Scalp hair starts to thin when more hairs are lost through normal shedding than the scalp is able to renew.
• Generalized hair loss (a uniform loss of hair) can be caused by a genetic predisposition (heredity), which is the most common reason. It also can be caused by illness, certain physical conditions, or their treatments.
• Patchy hair loss can be caused by ringworm or alopecia areata, a condition with an unknown cause
• Balding is a normal process that develops to some degree in all men and is influenced by male sex hormones, called androgens.
• Camouflage techniques to hide hair loss include the use of toupees and hairpieces, and a technique called hair weaving.
• Plastic surgery techniques to lessen the visible effects of baldness include hair transplantation, scalp flap transfer, skin expansion, and serial excision.
• Medications that can slow balding and, in some cases, help prevent hair loss include minoxidil and finasteride. Both of these medications can cause side effects.
• A gradual thinning of the hair frequently occurs in women as they grow older. But it differs from the hair loss experienced in men, because complete hair loss in women is hardly ever seen.
• The range of possible remedies for the treatment of thinning hair in women is similar to those available for men. Women should not take finasteride, however.
• Everyday ways to help prevent hair loss include eating a balanced diet, avoiding hair treatments or styles that can damage hair, and avoiding vigorous combing and brushing, especially if the hair is wet.

Hair Loss: Glossary

Here are definitions of medical terms related to hair loss.

Alopecia: Partial or complete lack of hair resulting from normal aging, physical disorders, drug reaction, anticancer medications, or skin disease

Alopecia areata: A disease in which well-defined bald patches occur; it usually clears completely within 6 to 12 months without treatment

Erector muscle: Tiny muscle at each hair shaft that is responsible for lifting the hair off the surface of the skin at times of stress or to conserve warmth

Hair follicle: A tiny tube of skin cells that contain the root of the hair shaft

Hair shaft: The protein material twisted into a very fine rope-like arrangement that is considered as “hair”

Hormones: Chemical messengers that produced by the body that stimulates activity by organs or tissues elsewhere in the body

Ringworm: A skin disease caused by a fungus that causes itching and scaling; when it occurs in the scalp, it can result in hair loss

Sebaceous gland: Tiny gland at each hair shaft that provides fats and greases to the hair

Hair Loss: Additional Sources Of Information

Here are some reliable sources that can provide more information on hair loss.

American Academy of Dermatology 
Phone: 847-330-0230
Phone: 1-888-462-DERM (3376) (toll-free) 
http://www.aad.org

American Society for Dermatologic Surgery 
Phone: 1-800-441-2737 Toll-free consumer hotline 
http://www.asds-net.org/