Hair care is an overall term for hygiene and cosmetology involving the hair which grows from the human scalp, and to a lesser extent facial, public and other body hair. Hair care routines differ according to an individual's culture and the physical characteristics of one's hair. Hair may be coloured, trimmed, shaved, plucked, or otherwise removed with treatments such as waxing, sugaring, and threading.
Care of the hair and care of the scalp skin may appear separate but are actually intertwined because hair grows from beneath the skin. The living parts of hair (hair follicle, hair root, root sheath, and sebaceous gland) are beneath the skin, while the actual hair shaft which emerges (the cuticle which covers the cortex and medulla) has no living processes. Damage or changes made to the visible hair shaft cannot be repaired by a biological process, though much can be done to manage hair and ensure that the cuticle remains intact.
Hair loss (alopecia) is a frequent concern for both men and women, although it is normal to shed some hair each day. People who experience more than normal hair loss may have the inherited tendency to "common baldness." Male pattern baldness is the most common cause of hair loss in men, with a receding hairline and baldness on the top of the head. Women may develop female pattern baldness in which the hair becomes thin over the entire scalp. Sudden and temporary loss of a large amount of hair may be related to the stress of an illness or recent delivery of a baby (telogen effluvium). Alopecia areata causes hair loss in small, round patches while tight elastics or braids may cause hair loss at the hairline (traction alopecia). Certain diseases (eg, thyroid problems, diabetes, and lupus), medicines, or poor nutrition may also cause hair loss.
Infections of the scalp include bacterial infection of hair follicles (folliculitis), infestation of head lice (pediculosis capitis), and fungal infection of scalp ringworm (tinea capitis). Itching and excessive flaking of the scalp are seen with both dandruff (seborrheic dermatitis) and psoriasis.
Split ends, known formally as trichoptilosis, happen when the protective cuticle has been stripped away from the ends of hair fibers.
This condition involves a longitudinal splitting of the hair fiber. Any chemical or physical trauma, such as heat, that weathers the hair may eventually lead to split ends. Typically, the damaged hair fiber splits into two or three strands and the split maybe two to three centimeters in length. Split ends are most often observed in long hair but also occur in short hair that is not in good condition.
Hair can be damaged by chemical exposure, prolonged or repeated heat exposure (as through the use of heat styling tools), and by perming and straightening. Oil is harmful for rough hair and for dry scalp as it decreases nourishment for hair leading to split and hair fall. When hair behaves in an unusual way, or a scalp skin disorder arises, it is often necessary to visit not only a qualified physician, but sometimes a dermatologist, or a trichologist. Conditions that require this type of professional help include, but are not limited to, forms of alopecia, hair pulling/picking, hair that sticks straight out, black dots on the hair, and rashes or burns resulting from chemical processes. Gel provides a shiny look but dries the hair and makes it rough.
Genetics and health are factors in healthy hair. Proper nutrition is important for hair health. The living part of the hair is under the scalp skin where the hair root is housed in the hair follicle. The entire follicle and root are fed by a supply of arteries, and blood carries nutrients to the follicle/root. Any time an individual has any kind of health concern from stress, trauma, medications of various sorts, chronic medical conditions or medical conditions that come and then wane, heavy metals in waters and food, smoking etc. these and more can affect the hair, its growth, and its appearance.