16 Sep The Causes of Hair Loss
The majority of women who have been on birth control pills, who have been pregnant, or who have been through menopause have had to contend with some degree of hair loss.
Hair is not alive, it is actually made up of dead cells. However, the hair follicles are alive.
The follicles are tiny pockets of live cells just under your skin that are fed by blood vessels that lead into them and by oil glands within the follicles. The oil from these glands also makes your hair shine.
The hair itself is made of a protein called keratin, which hardens hair. Keratin also hardens nails, which is why nails can often be affected by certain kinds of hair loss. Synthesis of protein requires a great investment of energy. When a person becomes ill or malnourished, the hair stops growing; when the illness or malnutrition is severe or prolonged, the hair will even fall out. When hair begins to grow back, that’s an early sign that recovery has begun.
Let’s look at some of the properties of hair:
- Melanin is produced by melanocytes. When melanoctyes can o longer produce as much melanin as is needed to keep the hairs colored because the tyrosinase enzymes that create melanin are lost, hair will turn white. Stress and physical illness can accelerate the graying process.
- Human hair is classified into two main types. Vellus hair is fine and can range from “peach fuzz” to hairs that are so fine they’re almost invisible except upon very close or microscopic inspection. Terminal hair is the coarser, longer, more visible hair.
- The average head has one hundred thousand hair follicles, but they are not all in the same growth phase at the same time. Hair grows about half an inch each month. Each strand will grow at this pace for about two to seven years in what is called the anagen Then each strand rests for a while in the catagen phase. It falls out in the telogen phase, which is often referred to as the shedding phase. Don’t be confused if you hear telogen referred to as a resting phase. In that instance, telogen applies to the hair follicle, which is resting when a hair sheds. When a strand falls out, another one is right behind it, about to break the surface of your scalp. At any given time, 90% of your hairs are in the growing phase.
- Normal hair loss in this cycle is between fifty and one hundred strands per day.
- Hair falls out and is replaced at staggered intervals from follicles all over your head, so that natural, cyclical hair loss is never noticed. You won’’ lose just front, top, side, or back hair at the end of a cycle -–hair falls out at various times from all parts of your head.
- Hormones’ effects are not limited to causing hair loss or preventing it. Higher levels of hormones can mean higher levels of oil in your hair follicles’ oil glands. Hormonal changes during pregnancy can cause hair to become more oily and can change curly hair to straight hair. Sometimes this change in curliness is permanent.
Varieties of Women’s Hair Loss
Alopecia is the medical term for excessive or abnormal hair loss. There are different kinds of alopecia. What all hair loss has in common, whether it’s in men or women, is that it is always a symptom of something else that’s gone wrong in your body. Your hair will remain on your head where it belongs if hormone imbalance, disease, or some other condition is not occurring. That condition may be as simple as having a gene that makes you susceptible to male or female pattern bladness or one of the forms of alopecia areata. Or it may be as complex as a whole host of diseases. Fortunately, hair loss may also be a symptom of a short-term event such as stress, pregnancy, and the taking of certain medications. In these situations, hair will grow back when the event has passed. Substances (including hormones), medications, and diseases can cause a change in the hair growth and shedding phases and in their durations. When this happens, synchronous growth and shedding occur. Once the cause is dealt with, hairs go back to their random pattern of growth and shedding, and your hair loss problem stops.
Causes of Hair Loss
The Hormone Connection
Dihydrotestosterone (DHT), a derivative of the male hormone testosterone, is the enemy of the hair follicles on your head. Simply put, under certain conditions DHT wants those follicles dead. This simple action is at the root of many kinds of hair loss, so it’s addressed first.
Androgenetic alopecia, commonly called male of female pattern baldness, is not due to the amount of circulating testosterone in your blood, but the level of DHT binding to receptors in scalp follicles. Testosterone converts to DHT with the aid of the enzyme Type II 5-alpha reductase, which is held in a hair follicle’s oil glands. DHT shrinks hair follicles, shortening a hair’s growth cycle. As it does this, a normal hair’s diameter lessens and lessens over time until the hair is tiny and fine. Ultimately, no hair can grow when the follicle goes completely dormant or dies.
There are natural and herbal treatments and now drugs on the market that can curb hair loss and prompt regrowth because of their ability to interfere with DHT’s follicle-killing mission by either inhibiting 5-alpha reductase, and therefore the amount of DHT that can be created out of testosterone, or by inhibiting DHT’s ability to bind to receptors in hair follicles. DHT is also the main culprit in prostate problems, which is why many natural treatments and drugs that are used to treat the prostate might also be used to prevent or treat hair loss.
The hormonal process of testosterone converting to DHT, which then harms hair follicles, happens in both men and women. Under normal conditions, women have a minute fraction of the level of testosterone that men have, but even a lower level can cause DHT-triggered hair loss in women. And certainly when those levels rise, DHT is even more of a problem. Those levels can rise and still be within what doctors consider “normal” on a blood test, even though they are high enough to cause a problem. The levels may not rise at all and still be a problem if you have the kind of body chemistry that is overly sensitive to even its regular levels of chemicals, including hormones.
Since hormones operate in the healthiest manner when they are in a delicate balance, the androgens, as male hormones are called, do not need to be raised to trigger a problem. Their counterpart female hormones, when lowered, give an edge to these androgens, such as DHT. Such an imbalance can also cause problems, including hair loss. DHT behaves quite differently elsewhere on the body. It’s actually thought to stimulate hair growth in follicles on the chest, back, shoulders, eyebrows and ears.
Geographical and cultural influences also affect hormones. Compared to Asian men, for example, Americans have more 5-alpha reductase, the enzyme that converts testosterone to DHT, and therefore have more body hair and more baldness. Scientists are studying the link that a culture’s food choices may play in the action of our hormones – a diet higher in fat that does not keep blood sugar constantly balanced may create conditions in the follicles’ oil glands that lead to the production of more 5-alpha reductase.
Baldness can also be self-perpetuating. In balding areas, the oil glands in the hair follicle become larger. Since these glands also hold the enzyme that converts testosterone to DHT, there’s a lot of the enzyme in these enlarged glands in balding areas, poised to further weaken the hair follicles. Oil gland activity is also increased by higher amounts of circulating hormones.
Hormones are cyclical. Testosterone levels peak in the fall and are lowest in the spring. During the spring low, hair grows the most. As testosterone levels rise, heading toward fall, so does hair loss. By fall, twice as much hair is lost than was lost in the spring. Both men and women have a similar hair growth seasonal cycle. The cyclic nature of both our hair and hormones is one reason hair loss can increase in the short term even when you are experiencing a long-term slowdown of hair loss (and long-term increase in hair growth) while on a treatment that controls hair loss.
When your body goes through something traumatic, like childbirth, malnutrition, a severe infection, major surgery, or extreme stress, many of the 90% of your hairs that are currently in the growing (anagen) phase or catagen (resting) phase can shift all at once to the shedding (telogen) phase. About three months after the event that triggered this shift, many of those 90% fall out at the same time. This phenomenon is called telogen effluvium. No treatment is usually needed since the hairs will all immediately begin the growing phase again. Some women, however, have chronic telogen effluvium, and treatments must be based upon what caused the “trauma” in the first place and upon the persistent conditions that may be contributing to this kind of continuous shedding.
This is the hair loss associated with chemotherapy. Since chemotherapy targets your body’s rapidly dividing cancer cells, your body’s other rapidly dividing cells, such as hair follicles I the growing (anagen) phase, are also greatly affected. Soon after chemotherapy begins, 90% or more of the hairs can fallout while still in the anagen phase.
Androgenic Alopecia (Female Pattern Baldness)
The majority of women with angrogenic alopecia have diffuse thinning on all areas of the head. Some women may have additional thinning in the front, top, and crown areas as well. This is due to the action of androgens (male hormones) that are typically present in small amounts. This type of hair loss can be caused by a variety of factors tied to the actions of hormones including: an androgen-secreting tumor, ovarian cysts, the taking of high androgen index birth control pills, pregnancy, menopause, hormone imbalance (including one caused by the thyroid) and even the body’s overreaction to “normal” hormone levels. Some women with androgenetic alopecia, especially those who have androgen-secreting tumors or ovarian cysts, may also have other androgenetic symptoms besides hair loss. These include acne, excess facial and body hair, and menstrual irregularities.
Patchy Alopecia (Alopecia Areata)
There are three kinds of patchy alopecia: alopecia areata in which patches of scalp hair fall out; alopecia totalis in which all scalp hair is lost; and alopecia universalis in which all scalp and body hair are lost.
The exact cause is not known. Currently, the prevailing theory is that it may be an autoimmune disorder, meaning that the immune system attacks something in the body as if it were a foreign invader – in this case, hair follicles.
Alopecia areata may also be genetic. In 20% of the cases, there’s a family history of the condition. It may also be linked to stress. It may occur gradually, first showing up as broken hairs that taper to a thinner end, or quickly, with a small, completely bald patch showing up within twenty-four hours.
Trichotillomania is the condition of twisting and pulling out one’s own hair. This behavior is usually seen in children or adolescents; it is found in adults less frequently. It’s associated with psychological stress or disorder. Some affected people don’t even consciously realize that they’re pulling out their hair.
This condition is caused by localized trauma to the hair follicles from tight hairstyles that pull at hair over time. If the condition is detected early enough, the hair will regrow. Braiding, cornrows, tight ponytails, and extensions are the most common styling causes.
Loose Hair Syndrome
This condition is noninflammatory and nonscarring, and it most often affects children. It can be patchy or diffuse, and when it’s extensive, it affects the back of the scalp far more than the front. This may be from the back of the head rubbing against a pillow.
In this syndrome, hair is loose and easily pulls out of the follicles. The remaining hair doesn’t grow very long and can be unruly and hard to comb or style. This condition most often affects blond hair.
The affected hairs are still in the active growth phase, but their root sheaths, which normally surround and protect the hair shafts, aren’t produced properly in the follicles, so hair is poorly anchored. This condition can be genetic and run in families. It can improve on its own as an affected child ages, but if the condition doesn’t develop until the child is five years old or older, the hair loss will be more persistent.
Iron Overload (Hemochromatosis)
Iron overload can be caused by a high intakeof iron or by the genetic disese hemochromatosis, in which the body isn’t able to break down and remove iron from the bloodstream. Hair loss can be a symptom of this serious disease. Hemochromatosis can be treated once diagnosed but can be life threatening when undiagnosed. All people who experience the onset of hair loss should ask their doctors to check their iron levels as a precaution.
Hair Loss from Cancer
Chemotherapy used to treat cancer may result in hair loss, but so can some cancers themselves, including skin cancers that destroy hair follicles or spread to them and cancers that originate elsewhere but spread to the skin and destroy the hair follicles. Cancers can disrupt the normal hormone activity and balance, causing hair loss. Cancer also depletes the body’s resources, vitamins, minerals and energy, leading to the loss of hair in a gradual, diffuse manner. These kinds of hair loss do not involve permanent damage to hair follicles, and the hair usually returns after the cancer is successfully treated.
When a doctor performs tests to diagnose hair loss, he or she should test the following:
- Hormone levels (DHEAS, testosterone, androstenodione, prolactin, follicular stimulating hormone, and leutinizing hormone)
- Serum iron
- Serum ferritin
- Total iron binding capacity (TIBC)
- Thyroid stimulating hormone (T3, T4, TSH)
- Complete blood count (CBC)
- Scalp biopsy
- Hair pull
- Densitometry (to check for miniaturization of the hair shaft under extreme magnification)
If you or someone you know is experiencing worrisome hair loss, feel free to drop me a line on the “contact us” page on this site. I treat patients locally at my Naturopathic practice in Vancouver, B.C. and worldwide via phone or Skype.
To your best health!
Dr Tasnim Adatya
Naturopathic Physician, Menopause Clinician, Acupuncturist, and Health Educator