(Scalp Hair Thinning Due to a Shift in the Hair Cycle)
The sudden loss of exaggerated amounts of scalp hair is quite a common complaint, particularly in women. This shift in the hair cycle, creating a hair loss pattern called “telogen effluvium”, usually occurs suddenly. This is not associated with isolated bald patches of the scalp, or with excessive crusting or infections of the hair follicles. It may “unmask” male/female pattern hair loss, revealing thinning on the top of the scalp. In these cases, treatment is required for both problems.
NORMAL HAIR CYCLE
When a scalp hair begins to grow in each individual hair follicle, it remains in the “growth phase” (anagen phase) for approximately three years. This average growth phase for the scalp hair creates hair that will grow to approximately mid-back level. Some people have a longer growth phase and can grow their hair until they can almost stand on it, while others with a shorter cycle, can grow their hair no longer than shoulder length. This is an individual genetic variation.
After the growth phase, the individual hair follicles, independent of each other, convert into a “resting phase” (telogen phase), and remain in this dormant stage for approximately three months. During this time, a new hair is suddenly stimulated to grow, which eventually “pushes out” the old hairs as you comb, brush, and wash your hair. You will see these hairs coming out all of the time. This resting hair has the typical white tip on the scalp-end of the hair. This white tip is not the root, but indicates that this hair was in the resting phase, and that another hair is replacing it in the same follicle. In the normal hair cycle, approximately 85% of hairs are in the growth phase at any one time and 15% are in the resting phase. With this ration, it has been calculated that the average person will lose 100 hairs per day. If you do not shampoo every day, you will notice that on the days you do shampoo, you will lose an exaggerated number of hairs. This is normal.
TELOGEN EFFLUVIUM MYTHS:
The hair cycle and the growth phase of your hair have nothing to do with having a tight scalp or a lack of blood flow to the scalp. The tightness of your scalp is genetically determined, and has nothing to do with “circulation”.
Telogen effluvium is not associated with frequent shampooing. In fact, the healthiest scalps and hair that I see are the patients who shampoo daily.
The length of hair does not affect the growth rate.
WHAT CAUSES TELOGEN EFFLUVIUM?
It is important to remember that after the triggering event that causes a shift in the hair cycle, it takes up to three months before the hair loss is noticed. Due to this delay, it is important to look back at least three months prior to the onset of your hair loss. Following are some of the common causes of telogen effluvium:
Pregnancy and Delivery – 8-12 weeks after the delivery of a child a scalp hair loss often occurs that can be quite frightening. This is temporary, and the hair cycle will re-establish itself.
A high fever (from any cause) is a common initiator of a shift in the hair cycle from the growth phase to the resting phase, the growth phase will return to normal.
Ingestion of various anticoagulants (blood thinners) can affect the hair cycle.
Birth control pills can initiate a shift in the hair cycle, either while the patient is on them or once the patient has stopped the pills. The same type of hair loss can be experienced as with the birth of a child.
Emotions – some patients have a very sensitive hair cycle and emotionally disturbing experiences can shift the hair cycle, creating an exaggerated hair loss.
Anemia, particularly iron deficiency anemia, can influence the hair cycle in a negative way.
Any severe, systemic illness can create a shift in the hair cycle.
Hypo- or hyperthyroidism can create telogen effluvium.
Diets – any crash diet program can create a shift in the hair cycle (the HCG weight control program often influences the hair cycle).
Correct the precipitating cause if it is ongoing.
Avoid aggressive combing, brushing, and back-combing of your hair.
Do not “over use” the hair dryer.
Use mild shampoos
It is important to have serum iron and iron binding capacity laboratory tests done, as there are significant number of patients who have low tissue iron levels who will not regain the growth phase of the hair without iron replacement.
It is very important to remember that once the hair cycle has shifted, it takes months for the hair cycle to re-establish itself, even in patients where the cause of the hair loss is easily determined and eliminated. Few patients never quite regain the volume of hair they had before the shift occurred. If you feel that your hair loss has gone past the preventative stage, you may need a hair loss treatment that is more intensive and more personalized to your particular issue. Thankfully there are plenty of options available in today’s market.
Zinc (Usually in the form of Stress Tabs with zinc and copper, 1 pill twice daily) and Rogaine lotion (1 ml twice daily to thin hair areas, is often helpful but may require many months of therapy).
As with any medical treatments, it is always important to check with your family doctor or dermatologist to see if any of the above medications or treatment regimens is right for you. For more information, please visit our dedicated hair transplant website at DrNakatsui.com
Dr. Thomas Nakatsui is the medical director of the Groot DermaSurgery Centre, a certified non-hospital surgical facility. Dr. Nakatsui is a dermatologist that specialises in ultra-refined hair transplantation, using the lateral slit technique. He is a Fellow of the Royal College of Physicians and Surgeons of Canada and is board certified in both the United States and Canada. He completed his medical training and residency in Dermatology at the University Of Alberta and received additional training at several Centres of Excellence including Harvard, the Johns Hopkins Medical Centre, the Massachusetts General Hospital, and the Mayo Clinic.