Hair loss, also termed alopecia in medicine, is a condition caused by an interference in your body’s normal hair growth cycle or damage to your hair follicles. These follicles are tunnel-shaped structures within your skin from which your hair grows. Each strand has a follicle that connects it to your skin. On average, you shed between 50 to 100 strands of hair daily as your hair cycles through different stages. However, any factor that upsets this cycle will cause your hair to shed excessively more than it regrows, leading to alopecia. Though hair loss most commonly affects the scalp, it is not exclusive to this body part and can occur anywhere on the body.
Hair growth cycle
Let's first talk about your natural hair growth cycle to understand why and how hair loss happens. Hair follicles do not constantly produce hair. They do so by cycling through three stages at separate times as follows:
Anagen (growth) phase
During this stage, your hair follicles are most actively dividing, so more new hair is grown. This stage typically lasts two to five years. At any given time, about 80% to 90% of healthy hair follicles are in this stage.
Catagen (transitional) phase
Following the anagen phase, your hair follicles move into a brief transitional phase known as the catagen phase. This phase heralds the end of active hair growth and causes hair follicles to dwindle. It lasts about one to two weeks.
Telogen (resting) phase
Before producing new hair fibers, hair follicles go into a resting phase known as the telogen phase. It typically lasts around three months. At any given time, about 5–10% of your hair is in this phase. Before re-entering the growth phase, your hair falls out from its follicle.
Causes of hair loss
Many factors contribute to hair loss. What triggers hair loss determines if your hair can regrow on its own or not, such as:
High levels of stress. A body under stress can force hair follicles to stay resting for a typically more extended period, causing them to fall out eventually. This stress-induced hair loss, called “telogen effluvium (TE),” is transient and reversible, lasting up to 6 months.
Causes of stress-related hair loss include:
- Sickness, like COVID-19
- Financial distress
- A relationship breakup or divorce
- Giving birth
Nutritional deficiencies. A poor diet may wreak havoc on your hair anatomy and growth. The deficiency of essential nutrients like vitamins B3, E, D, iron, zinc, biotin, and proteins can trigger severe hair loss. Taking a regular, healthy diet is therefore imperative.
Hereditary hair loss. According to the American Academy of Dermatology, hereditary hair loss is the most common cause of baldness. Experts refer to hereditary hair loss as androgenic alopecia. This type of hair loss follows a predictable pattern and is often known as male pattern baldness or female pattern baldness. The gene responsible for this type of hair loss is the androgen receptor gene. This gene boosts the androgen receptor activity and thus augments the androgen levels. Unlike telogen effluvium, hereditary hair loss is permanent if not treated on time.
Certain bad hair habits also trigger hair loss in the long run, such as:
- Females may wear hairstyles that tend to cause constant pulling on their hair, leading to bald spots known as traction alopecia. Hairstyles like tight, high ponytails, wet messy buns, and tight braids repeatedly stress your hair out.
- Overusing hot styling tools tends to strip off the moisture, making it prone to breakage.
Trichotillomania. This mental health problem induces an irresistible urge to pull out hair from your scalp or other body parts. These people inappropriately use hair pulling to cope with negative emotions, such as stress, boredom, or anxiety.
Alopecia areata. When your immune system strongly disagrees with accepting your hair follicles as a part of your body, a condition called alopecia areata ensues. Surprisingly, the hair loss is not permanent in most cases as the follicles preserve their ability to regrow hair.
Medications like chemotherapy drugs can interfere with your hair growth and cause hair loss.
Gender. According to the American Hair Loss Association: roughly 85% of men will have remarkable hair thinning by age 50. In contrast, research shows that up to 40% of women will have noticeable hair loss by age 50.
Gender differences in hair loss patterns
Patterns of hair loss in men and women differ. In males, hair loss is most prominent in the front and sides of the head. Thus, a receding hairline is one of the very first signs of male pattern baldness. In comparison, women's hairline rarely recedes. Hair loss in women usually begins at the part line, followed by diffuse hair loss spreading from the top of the head.
When to see a doctor?
If you have hair loss that you feel is out of the norm, such as seeing lots of hair on your pillow when you wake up or in the drain while you shower, it's time to see your doctor. You should consult a board-certified dermatologist for an accurate diagnosis and timely treatment.
What is the treatment for hair loss?
If your hair loss is due to an underlying problem, addressing that problem may help slow down the rate of hair loss. Treatments for hair loss include medications, surgery, laser therapy, and preventive measures.
Medications like minoxidil (Rogaine) and finasteride (Propecia) are often the first lines of treatment. Minoxidil is an off-label treatment available in liquid, foam, and shampoo forms. Finasteride is a prescription medication that lowers your hormone levels which may otherwise promote hair loss.
Olumiant is another FDA (Food and Drug Administration)-approved medication that works to calm down the hyperactive immune system in patients with severe alopecia areata.
Hair transplant, or restoration surgery, entails restoring the bald patches on your scalp by transplanting micro grafts of hair from the donor to the affected areas.
Remember that an ounce of prevention is worth a pound of cure. Thus, be sure to take the following preventive measures as soon as you notice hair loss:
- Be mindful of your hairstyling habits. If you’re a female, wear your hair in loose buns or braids.
- Cut down on heat styling.
- Learn to manage stress.
- Take a regular, well-balanced diet packed with vitamins and minerals.
- Massage your head for at least 5 minutes at a time, several times a day. Research shows that massaging your scalp can also supercharge your hair follicles and boost hair growth.
Low-level laser therapy also stimulates hair follicles and promotes hair growth.
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