It had been thought that most hair found in the sink or shower, on the brush etc. was broken hair due to damage and weathering. Studies have now shown this not to be the case. In fact at least 80% of hair loss is from the root, not breakage.
Yahoo Lifestyle Entertainment – 9 hours ago
The hair shaft is a remarkable structure that takes a great deal of abuse, ranging from exposure to the environment, and to frequent combing and brushing. Normal hair keeps its resiliency, flexibility, and strength for up to 7 years, unless there are genetic defects present. During the time that hair is on the scalp and before it is shed, there may be some breakdown. This is often called “weathering,” which is characterized by changes in the hair structure, generally limited to cosmetic occurrences. Weathering is due to: “combing, brushing, and permanent waving...natural friction, wetting, and ultraviolet radiation.”
It had been thought that most hair found in the sink or shower, on the brush etc. was broken hair due to damage and weathering. Studies have now shown this not to be the case. In fact at least 80% of hair loss is from the root, not breakage.Data generated by hair experts confirms this observation and extended it to a range of ethnic communities globally. The highest rates of shedding from the root appear in China (>90%) and in all cases (Mexico, India, Turkey, Thailand, UK) shedding from the root was always greater than 80%.
BREAKAGE:
Breakage is characterized by broken and/or blunted ends and differs from growing hair that may have pointed or tapered tips.
Fragile hair will easily break off near the ends: hence hair breakage. If there is a question of broken hair, this can be confirmed in two ways:
• Card test - hold an index card behind the hair in question (white for darker colors and black for lighter colors). This will highlight the broken or blunted tips of breakage.
• Tug test – grasp a few centimeters or inches of hair from the ends. If the hair is damaged, the held areas will fragment.10 Bubble hair can result from excessive blow drying, flat ironing, or hot curlers due to the high temperatures involved. This may lead to broken hair, as well as changes in texture and strength. The hair will show bubbles within the shaft under magnification.
Acquired trichorhexis nodosa: Although this hair shaft fracture, which gives the picture of two brooms meshed together, is usually due to heredity, heat, straighteners, and excessive combing or brushing can induce it. The fractured hair gives the appearance of nodes being present. This condition also shows cultural differences: distal disruption is often found in Caucasian and Asian women, while women of African descent have the problem closer to the scalp. Attempting to brush the nodes out can cause even more damage.
HAIR LOSS:
TELOGEN EFFLUVIUM: This represents the loss of hair due to abnormal hair cycling. The amount of daily shedding is in excess of 100 hairs per day. If telogen effluvium lasts for less than six months, it is called acute, and if more than six months, it is referred to as chronic. At least 50% of the scalp hair needs it to become lost for the loss to be clinically visible. Acute telogen effluvium may be due to anything that increases the body’s metabolism, such as severe illness, certain drugs, fevers, or even iron and vitamin D deficiency. Acute telogen effluvium occurs three to six months after pregnancy and can even appear when birth control pills, which create a pseudo-pregnancy state, have been stopped. The hair cycle usually returns to normal within a few to several months.
ANAGEN EFFLUVIUM: This type of hair loss occurs most frequently after treatment with cancer therapeutic agents or with radiation. Mostly broken hairs, rather than hair loss, characterize anagen effluvium. Such hair loss usually begins seven to ten days after the start of treatment but does not become noticeable for one to two months. It generally continues for another month after the last treatment cycle.13 Occasionally, the new hair is weaker and more brittle. At other times, some patients believe their hair grows back healthier and with different coloring. In addition, people with curly hair may find their hair straightened and vice versa. Anagen effluvium can also occur with arsenic or thallium poisoning.
ANDROGENIC ALOPECIA (PATTERNED HAIR LOSS): This is the most common type of hair loss (95%) in both men and women, where there is a progressive loss of hair diameter, length, and pigmentation.14 There is a genetic influence, but the causative genes have yet to be found. While the precipitating factors are often unknown, a few people have lost hair from massive weight gain or losses or from taking prescription medicines with androgenic effects. Oral contraceptives and hormonal replacement agents have rarely been held responsible for inducing or aggravating androgenic alopecia.
PRESCRIPTION MEDICINE INDUCED HAIR LOSS: Infrequently, some therapeutic agents have been known to cause hair loss. These include: allopurinol for the treatment of gout, heparin and warfarin for preventing blood clots, and clofibrate and gemfibrozil for lowering cholesterol levels. ALOPECIA AREATA: This condition occurs, often suddenly, with small, frequently rounded, patches of hair loss on the scalp. There is the noticeable appearance of abnormal club hairs that resemble exclamation points. While the cause is unknown, the hair usually returns spontaneously within six to twelve months, but the condition can recur.
TRICHOTILLOMANIA: This self-induced hair loss results from frequent pulling and tugging of the scalp hair, eyebrows, and even eyelashes. It occurs twice as often in girls or women than in boys or men. Trichotillomania represents a psychiatric problem of children and adolescents. The bald spots have irregular borders and contain many broken hairs.
TRACTION ALOPECIA: Such hair loss results from chronic insults to the hair follicle. When the hair is pulled too much or placed in tight curlers, the follicle eventually gives up and no longer is able to produce hair. This is often accompanied by chemical alopecia, where the follicles have been injured by frequent use of straighteners or relaxers. Applying a hot comb or hot rollers, or using a heated iron without being careful, can also lead to hair loss (hot comb alopecia: when the scalp is burnt by the instrument or the melting petrolatum, or the hair shaft is weakened and broken due to thermal injury).
TINEA CAPITIS: Also known as ringworm, this is a fungal infection of the scalp, where the hair breaks off, and there are scaling, crusted, reddened areas on the scalp. With some fungal infections, bacteria co-infect these patches, which then swell and are referred to as a kerion. This is usually a condition of children and is rarely seen in adults.
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