TYPES OF HAIR
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Three types of hair grow on the human body.
- The first postnatal hair is vellus hair, soft, usually unpigmented, remains on the
hairless regions of the body like forehead
- At puberty, the vellus hair in some areas is replaced by terminal hair, which are
long hair that grow on the head and in many people on the body, arms and legs too.
Body hair continues to develop long after puberty, stimulated by male hormones that
paradoxically, also cause terminal hair to be replaced by vellus hair when balding
begins.
- Lanugo hair- This is the hair that develops on an unborn baby.
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HAIR LOSS IN MEN AND WOMEN
Hair loss usually develops gradually and may be patchy or diffused (all over). Roughly
100 hair are lost from the head every day. The average scalp contains about 100,000
hair. Each individual hair survives for an average of 4½ years, during which
time it grows about half an inch a month. Usually in its 5th year, the hair falls
out and is replaced within 6 months by a new one. Genetic baldness is Hcaused by
the body's failure to produce new hair and not by excessive hair loss.
By far, the most common form of hair loss is determined by our genes and hormones,
also known as and rogen-dependent, androgenic, or genetic hair loss. It is the largest
single type of recognizable alopecia to affect both men and women.
HAIR PROBLEMS ARE NOTHING BUT MANIFESTATIONS OF ALLERGY
Hair problems may be due to cosmetic causes, such as Huse of harsh shampoos and
blow-drying, or due to under the lying diseases, such as thyroid problems but the
inherent cause is Allergy.
CONCEPT OF ALLERGY
Allergy (Greek: allos, other + ergon,work = altered reaction) is an abnormal and
individual hypersensitivity to substances that are ordinarily harmless and which
results in various types of reactions. Pollens, for example, are generally harmless,yet
many people are acutely sensitive or allergic to their presence.
WHY DOES A PERSON DEVELOP ALLERGY?
Normally, a person's immune system clearly distinguishes s Nbetween harmful and
harmless foreign bodies and it reacts only to harmful bodies like various pathogenic
bacteria and virus. When immune system fails to recognize harmless bodies as "harmless"
it reacts to it and produces various symptoms in the form of allergic manifestations.
MECHANISM OF ALLERGIC RESPONSE
When an allergen enters our body, the IgE and the allergen forms a complex. This
complex then binds to the mast cell. As a result underthe mast cell bursts and releases
histamine. This histamine produces the allergic symptoms such as redness, swelling,
heat, itching etc.
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