Prevalence
Hair loss among men is one of the frustrating situations that occur as you age. The loss may not be noticed as first, but once thinning or a receding hairline becomes visible, a significant amount of hair has fallen. It is insidious and surreptitious! While some men embrace the blad style, others feel that the loss hinders their looks and makes them appear older.
By the time you are 50 about 85% of your peers have thinning of hair. In extreme situations, some men start to lose hair before they turn 21. In the United States alone, according to the National Institutes of Health (NIH), male pattern baldness, or androgenic alopecia, affects an estimated 50 million men and 30 million women.
Hair growth cycle
Underneath you scalp, the skin covering of your head, you have around 150,000 hair follicles. It is from these follicles that new hairs grow and sprout. At any one time 80-90% of your hairs are in the anagen, or growing phase. Throughout the hair life cycle, your hairs are in various stages of growth and shedding.
The four stages of hair growth are:
1. Anagen (Growing Phase)
The anagen phase usually lasts from 2 to 7 years and the length of this phase determines the length of your hair.
2. Catagen (Transition Phase)
This is the transitional phase that lasts about ten days. During this stage, your hair follicle decreases in size and detaches from the dermal papilla.
3. Telogen (Resting Phase)
The telogen phase lasts around three months. Around 10-15% of your hairs are in this phase at any given time. While the old hairs are resting, the new hairs are in the growing phase.
4. Exogen (Shedding Phase)
This is actually part of the resting phase when the old hairs detach and shed and new hairs continue to grow. Around 40 to 120 of your hairs may fall out daily, and this is the normal rate of your hair shedding. In hereditary hair loss, your follicles shrink and the growth cycle is shortened as a result of changes in the availability of hormones.
Aside from the shortening of the growth cycle, the ensuing cycle produces shorter, finer, and much less visible hair. In time, follicles will be destroyed and fail to grow or produce hair. There are a number of factors that could cause hair loss, but the most common cause in men and women is a condition called androgenic alopecia (AGA). Heredity, hormones, and age play a part in AGA and is why the follicles shrink.
Normal hair loss
Normally, your head contains 100,000 strands of hair and you lose around 40 to 120 strands per day. This amount is normal and is a part of healthy re-growth cycle. Shedding and regrowth are needed for rejuvenating and renewing the health and condition of your hair.
Normal hair loss occurs because your scalp hair grows in cycles. Each of your hair follicle undergoes a growth stage that lasts two to eight years, followed by a two-month resting stage where no growth occurs at all. Then the hair strand falls out and a new one begins to grow in its place. In a nutshell, for a healthy person, this means that between 80 to 90 percent of hair follicles are growing hair at one time, while the rest of the follicles are resting or shedding.
Abnormal hair loss
When you are not experiencing hair loss, you will notice that as you brush your hair nothing is left behind in your comb—or only a few strands. However, if you are experiencing increased hair loss, you will be brushing out more hair than usual. As times elapses, you may start to notice a receding hairline, thinning top, or a more pronounced hairline at the sides. These are signs that you are experiencing hair loss.
Your hair loss could be caused by a medical disorder, a prescribed medication, poor nutrition, bad hair techniques, or severe stress. In 95% of cases, however, the cause is hereditary and the resulting hair loss is known as male pattern baldness or androgenic alopecia. In this common condition, you experience thinning of hair on your scalp, a receding hair line and/or balding on the top of your head. These changes typically start to occur in some men in their 20s and become more common with age. Once hair loss has occurred over a long period of time, your hair may be permanently lost, which is why many treatments focus on slowing loss rather then trying to grow the lost hair.
Male pattern hair loss is thought to be caused by a combination of family history (heredity) and production of a particular male hormone which is called dihydrotestosterone (DHT). DTH is actually derived from another hormone, popularly known as testosterone. Men with male pattern hair loss have more DHT in the balding part of their scalp than in other parts, resulting in increased hair loss.
In hereditary hair loss, the genes and hormones in your body have a shrinking effect on your hair follicles, making them ineffective in growing and generating new hairs. Over time, the progressive shrinking of certain scalp follicles leads to a shortening of your hair’s growth cycle. New hairs become thinner, finer, and shorter until there is no growth at all and the follicles become dormant. This is caused by hormones and certain genes, acting together to cause the losing of your hair.
Types of hair loss
Male pattern baldness
Male pattern baldness (MPB) has a distinctive shape. The front hairline recedes, especially at the sides, forming an M shape. This is frontal baldness. The crown of the head, also known as the vertex, becomes bald as well. Eventually, the two areas join into a “U” shape. MPB can even extend to chest hair, which can thin as you age. Oddly enough, hair in different locations on your body can react differently to hormonal changes. For instance, facial hair growth can improve while other areas become bald.
Alopecia areata or patchy hair loss
If you have one to two totally smooth, round patches of hair loss mostly on your scalp, you may be suffering from alopecia areata or patchy hair loss. The hair loss may also be seen in the eyebrows, arms, legs, or face. It is often sudden in onset and the hair usually grows back in six months to a year. However, when the hair grows back in one area, it may fall out in another. In some people the hair may become thinner without patches of baldness. In others, it may grow and break off, leaving short stubs which resemble “exclamation points.”
Involutional alopecia
The rate of hair growth slows as you age, causing the thickness as well as volume of your hair to be reduced. In this type of hair loss which is known as involutional alopecia, your hair follicles gradually go into the telogen (resting) phase. The remaining hair becomes shorter and fewer in number, sometimes even brittle.
Tinea capitis
Tinea capitis (ringworm of the scalp) is a fungal infection of the scalp which usually affects school-age children and goes away at puberty. It is rare in healthy adults. It involves either some parts or whole of the scalp. Hair breaks off at areas that are infected by the fungus causing bald scalp with small black dots. The skin has inflamed (red swollen), round, scaly areas with pus-filled sores called kerions. The child afflicted with this may experience low-grade fever or swollen lymph nodes in the neck. It is contagious and can spread from sharing combs and hats. Once the infection is controlled, the hair grows back.
Telogen effluvium
You may experience temporary hair loss weeks to months after having stressful episode in your life, like childbirth, fever, severe illness, reviewing for a board and licensure examination, or sudden weight loss. Later, in a few months, when the stress is successfully resolved, your hair loss gradually decreases. Such type of hair loss is called telogen effluvium. This happens due to changes in the growth cycle of your hair, when a large number of them go into the resting phase (telogen) at the same time.
It is not only stress that causes telogen effluvium; intake of some drugs could also cause it. In fact, it is the most common form of drug-induced hair loss. It usually appears within 2 to 4 months after taking the incriminated drug. This condition causes the hair follicles to go into their resting phase (telogen) and fall out too early. If you are afflicted with this, you usually shed strands of hair between 30% to 70% more than the normal shedding which is between 100 to 150 hairs per day.
Anagen effluvium
Anagen effluvium is hair loss that occurs during the anagen phase of your hair cycle, when your hairs are actively growing. It prevents the matrix cells, which generate new hairs, from dividing normally. This type of hair loss usually occurs within a few days to weeks after taking the suspected medication. If you have been receiving one or more chemotherapeutic drug(s)—medications to treat cancer—you will suffer from this type of hair loss, and it is often severe, causing you to lose most or all of your hairs on your head, including hairs from your eyebrows, eyelashes, and other parts of your body. The severity of drug-induced hair loss depends on the type of drug that you received and its dosage, as well as your sensitivity to such drug.
Traction alopecia
Hair loss can also occur due to pressure applied on your hair by particular hairstyles, causing small, localised areas of hair loss. This type of hair loss is called traction alopecia.
Trichotillomania
Some people have the habit of voluntarily twisting or pulling their own hair from the scalp and eyelashes. This is referred to as trichotillomania or hair pulling disorder. It is a psychological disorder seen most frequently in children. Hair patches in this condition show broken-off hairs.
