Hair care
Encyclopedia
Hair care is an overall term for parts of hygiene
and cosmetology
involving the hair
on the human head. Hair care will differ according to one's hair type and according to various processes that can be applied to hair. All hair is not the same; indeed, hair is a manifestation of human diversity.
In this article, 'Hair care' is taken to mean care of hair on the human head, but mention should be made of process and services which impact hair on other parts of the body. This includes men‘s and women’s facial, pubic, and other body hair, which may be colored
, trimmed, shaved
, plucked, or otherwise removed with treatments such as waxing
, sugaring
, and threading. These services are offered in salons
, barber
shops, and day spa
s, and products are available commercially for home use. Laser hair removal and electrolysis
are also available, though these are provided (in the US) by licensed professionals in medical offices or speciality spas.
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.
Scalp skin, just like any other skin on the body, must be kept healthy to ensure a healthy body and healthy hair production. If the scalp is not cleaned regularly, by the removal of dead skin cells, toxins released through the skin or external hazards (such as bacteria, viruses, and chemicals) may create a breeding ground for infection. However, not all scalp disorders are a result of bacterial infections. Some arise inexplicably, and often only the symptoms can be treated for management of the condition (example: dandruff
). There are also bacteria
that can affect the hair itself. Head lice is probably the most common hair and scalp ailment worldwide. Head lice can be removed with great attention to detail, and studies show it is not necessarily associated with poor hygiene. More recent studies reveal that head lice actually thrive in clean hair. In this way, hair washing as a term may be a bit misleading, as what is necessary in healthy hair production and maintenance is often simply cleaning the surface of the scalp skin, the way the skin all over the body requires cleaning for good hygiene.
The sebaceous gland
s in human skin produce sebum, which is composed primarily of fatty acid
s. Sebum acts to protect hair and skin, and can inhibit the growth of microorganisms on the skin. Sebum contributes to the skin’s slightly acidic natural pH
somewhere between 5 and 6.8 on the pH spectrum. This oily substance gives hair moisture and shine as it travels naturally down the hair shaft, and serves as a protective substance preventing the hair from drying out or absorbing excessive amounts of external substances. Sebum is also distributed down the hair shaft “mechanically” by brushing and combing. When sebum is present in excess, the roots of the hair can appear oily, greasy, and darker than normal, and the hair may stick together.
, which is the skin's own protective layer.
Washing hair removes excess sweat and oil, as well as unwanted products from the hair and scalp. Often hair is washed as part of a shower
or bathing
with shampoo
, a specialized surfactant. Shampoos work by applying water and shampoo to the hair. The shampoo breaks the surface tension of the water, allowing the hair to become soaked. This is known as the wetting action. The wetting action is caused by the head of the shampoo molecule attracting the water to the hair shaft. Conversely, the tail of the shampoo molecule is attracted to the grease, dirt and oil on the hair shaft. The physical action of shampooing makes the grease and dirt become an emulsion that is then rinsed away with the water. This is known as the emulsifying action.
Shampoos have a pH of between 4 and 6 and do not contain soap. Soapless shampoos are acidic and therefore closer to the natural pH of hair. Acidic shampoos are the most common type used and maintain or improve the condition of the hair as they don't swell the hairshaft and don't strip the natural oils.
Conditioners are often used after shampooing to smooth down the cuticle layer of the hair, which can become roughened during the physical process of shampooing. There are three main types of conditioners: anti-oxidant conditioners, which are mainly used in salons after chemical services and prevent creeping oxidation; internal conditioners, which enter into the cortex of the hair and help improve the hair's internal condition (also known as treatments); and external conditioners, or everyday conditioners, which smooth down the cuticle layer, making the hair shiny, combable and smooth. Conditioners can also provide a physical layer of protection for the hair against physical and environmental damage.
Chemical alteration of hair only affects the hair above the scalp; unless the hair roots are damaged, new hair will grow in with natural color and texture.
is the process of adding pigment to or removing pigment from the hair shaft. Hair coloring processes may be referred to as coloring or bleaching, depending on whether you are adding or removing pigment.
Temporary hair tints simply coat the shaft with pigments which later wash off.
Most permanent color changes require that the cuticle of the hair be opened so the color change can take place within the cuticle. This process, which uses chemicals to alter the structure of the hair, can damage the cuticle or internal structure of the hair, leaving it dry, weak, or prone to breakage. After the hair processing, the cuticle may not fully close, which results in coarse hair or an accelerated loss of pigment. Generally, the lighter the chosen colour from one's initial hair color, the more damaged it may be. Other options for applying color to hair besides chemical dyes include the use of such herbs as henna
and indigo
, or choosing ammonia-free solutions.
or thermal reconditioning involve chemical alteration of the internal structure of the hair in order to affect its curliness or straightness.
Hair that has been subjected to the use of a permanent is weaker due to the application of chemicals, and should be treated gently and with greater care than hair that isn't chemically altered.
Calcium causes hair to feel dry and lack shine and volume. It can prevent the proper processing of color, highlights, perms or relaxer/straighteners and can cause a perm to appear relaxed. Calcium builds up on the scalp causing flaking of the scalp, giving the appearance of dandruff. Calcium can choke the hair at the mouth of the follicle causing the hair to break off, then coat the scalp, blocking further new hair growth.
Iron can cause water to have a red or rusty hue. Iron leaves hair feeling dry, brittle and weighted down. It causes lack of shine and can cause dark hair to tint darker and blonde hair to turn orange. Iron can inhibit the proper processing of perms, color, highlights, and relaxers/straighteners
Copper discolors hair causing blonde hair to turn green and dark hair to tint darker. Copper can weigh hair down and cause dryness, and can inhibit the proper processing of perms, color, highlights, and relaxers/straighteners.
Magnesium causes hair to lack shine, feel dry, appear weighted down therefore lacking volume, and can inhibit the proper processing of perms, color, highlights, and relaxers/straighteners.
Silica causes many of the same effects on the hair as calcium. It causes hair to feel dry, lack volume, and can cause dandruff-like symptoms of flaking. Build-up of silica can choke the hair follicle causing hair to fall out.
Lead can cause the hair to feel dry. Lead can prevent the proper processing of perms, color, highlights, and relaxers/straighteners.
Typically, these minerals can be found in groundwater
usually extracted using a well
. The level of calcium that is found naturally from the ground determines the hardness of water. While calcium is the element that determines hardness of water, there are many other elements in well water that affect hair, scalp and skin.
To improve the hair health and further prevent issues with dryness and buildup, people can use a shower head filter that will remove the minerals found in most city waters. However, hard water minerals and the sanitizing agents like Chlorine and Chloramine can also deposit in or on the hair, building up over time. The chemical and mineral content of water varies by geography. Filtering water through very fine mesh cloth may help to remove larger deposits in the water. Many enjoy collecting rain water, although acid rain is an increasing issue in many parts of the world.
Treatment for well water and hard water conditions are available in a variety of products, such as demineralizing shampoos and conditioners.
Those who swim in chlorinated or salt sea water may benefit from first wetting the hair entirely and then applying conditioner to completely swell the entire hair shaft. Swimmers may also benefit from products on the market that remove chlorine after swimming in pool water.
, 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 may be 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.
As hair grows, the natural protective oils of the scalp
can fail to reach the ends of the hair. The ends are considered old once they reach about 10 centimeters since they have had long exposure to the sun, gone through many shampoos and may have been overheated by hair dryers and hot irons. This all results in dry, brittle ends which are prone to splitting
. Infrequent trims and lack of hydrating treatments can intensify this condition.
.
, hair pulling/picking, hair that sticks straight out, black dots on the hair, and rashes or burns resulting from chemical processes.
There are a number of disorders that are particular to the scalp. Symptoms may include:
Any of these symptoms may indicate a need for professional assistance from a dermatologist or trichologist for diagnosis.
Scalp skin can suffer from infestations of mites, lice, infections of the follicles or fungus. There could be allergic reactions to ingredients in chemical preparations applied to the hair, even ingredients from shampoo or conditioners. Common concerns surrounding dandruff (often associated with excessive sebum); psoriasis, eczema, or seborrheic dermatitis.
An odor that persists for a few weeks despite regular hair washing may be an indication of a health problem on the scalp skin.
Not all flakes are dandruff. For example, some can merely be product buildup on the scalp skin. This could result from the common practice of applying conditioner to scalp skin without washing. This would dry upon the scalp skin and flake off, appearing like dandruff and even causing itchiness, but have no health effects whatsoever.
Particularly among women, thyroid disease is one of the more under-diagnosed health concerns. Hair falling out in clumps is one symptom of a set of symptoms that may indicate a thyroid concern. In many gynecological exams a blood screen for thyroid is now a common protocol. Thyroid often shows up first in the behavior of the hair.
During pregnancy and breast feeding, the normal and natural shedding process is typically suspended (starting around month three because it takes a while for the body to recognize and reset for the hormonal shifts the body goes through) for the period of gestation and extended longer if one breast feeds (this includes pumping for breast milk). Upon cessation of either of these, it typically takes around two months for the hormones to shift again to the normal hormonal settings, and hair shedding can increase exponentially, for approximately 3–6 months until hair returns to its normal volume. It is commonly noticed that hair seems thicker and shinier, even, during pregnancy and breast feeding in response to the influx of shifting hormones. It is not unusual also for hair color to change, or hair structure to change (e.g., straighter hair, curlier hair). These changes can occur more often than people may realize yet isn't often reported.
is important for hair health. The living part of 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 vein, 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.
Generally, eating a full diet that contains protein, fruits, vegetables, grains, and even an appropriate amount of fat is important (several vitamins and minerals require fat in order to be delivered or absorbed by the body). Any deficiency will typically show first in the hair. A mild case of anemia
can cause shedding and hair loss. Among others, the B group of vitamins are the most important for healthy hair, especially biotin. B5 (pantothenic Acid) gives hair flexibility, strength and shine and helps prevent hair loss and graying. B6 helps prevent dandruff and can be found in cereals, egg yolk and liver. Vitamin B12 helps prevent the loss of hair and can be found in fish, eggs, chicken and milk.
When the body is under strain, it reprioritizes its processes. For example, the vital organs will be attended to first, meaning that healthy, oxygenated blood may not feed into the hair follicle, resulting in less healthy hair or a decline in growth rate. While not all hair growth issues stem from malnutrition, it is a valuable symptom in diagnosis.
Scalp hair grows, on average, at a rate of about half an inch per month, and shampoos or vitamins have not been shown to noticeably change this rate. Hair growth rate also depends upon what phase in the cycle of hair growth one is actually in; there are three phases. The speed of hair growth varies based upon genetics
, gender
, age, hormones, and may be reduced by nutrient
deficiency (i.e., anorexia, anemia, zinc deficiency) and hormonal fluctuations (i.e., menopause, polycystic ovaries, thyroid disease).
The essential omega-3 fatty acids, protein
, vitamin B12
, and iron
, found in fish sources, prevent a dry scalp and dull hair color. Dark green vegetables contain high amounts of vitamins A and C, which help with production of sebum and provide a natural hair conditioner. Legumes provide protein to promote hair growth and also contain iron, zinc
, and biotin. Biotin
functions to activate certain enzymes that aid in metabolism of carbon dioxide as well as protein, fats, and carbohydrates. A deficiency in biotin intake can cause brittle hair and can lead to hair loss. In order to avoid a deficiency, individuals can find sources of biotin in cereal-grain products, liver, egg yolk, soy flour, and yeast. Nuts contain high sources of selenium
and therefore are important for a healthy scalp. Alpha-linoleic acid and zinc are also found in some nuts and help condition the hair and prevent hair shedding that can be caused by a lack of zinc. Protein deficiencies or low-quality protein can produce weak and brittle hair, and can eventually result in loss of hair color. Low-fat dairy products are good sources of calcium
, a key component for hair growth. A balanced diet is extremely necessary for a healthy scalp and furthermore healthy hair.
Hygiene
Hygiene refers to the set of practices perceived by a community to be associated with the preservation of health and healthy living. While in modern medical sciences there is a set of standards of hygiene recommended for different situations, what is considered hygienic or not can vary between...
and cosmetology
Cosmetology
Cosmetology is the study and application of beauty treatment. Branches of specialty including hairstyling, skin care, cosmetics, manicures/pedicures, and electrology....
involving the hair
Hair
Hair is a filamentous biomaterial, that grows from follicles found in the dermis. Found exclusively in mammals, hair is one of the defining characteristics of the mammalian class....
on the human head. Hair care will differ according to one's hair type and according to various processes that can be applied to hair. All hair is not the same; indeed, hair is a manifestation of human diversity.
In this article, 'Hair care' is taken to mean care of hair on the human head, but mention should be made of process and services which impact hair on other parts of the body. This includes men‘s and women’s facial, pubic, and other body hair, which may be colored
Hair coloring
Hair coloring is the practice of changing the color of hair. Common reasons are to cover gray hair, to change to a color regarded as more fashionable or desirable, and to restore the original hair color after it has been discolored by hairdressing processes or sun bleaching...
, trimmed, shaved
Shaving
Shaving is the removal of hair, by using a razor or any other kind of bladed implement, to slice it down to the level of the skin. Shaving is most commonly practiced by men to remove their facial hair and by women to remove their leg and underarm hair...
, plucked, or otherwise removed with treatments such as waxing
Waxing
Waxing is a method of semi-permanent hair removal which removes the hair from the root. New hair will not grow back in the previously waxed area for two to eight weeks, although some people will start to see regrowth in only a week. Almost any area of the body can be waxed, including eyebrows,...
, sugaring
Sugaring (epilation)
Sugaring, sugar waxing or Persian waxing is a method of hair removal.It has been in use since 1900 BC.Sugaring can be less painful than waxing, because the substrate sticks to the hair without attaching to the skin, may be applied at room temperature or heated to a lukewarm temperature, preventing...
, and threading. These services are offered in salons
Beauty salon
A beauty salon or beauty parlor is an establishment dealing with cosmetic treatments for men and women...
, barber
Barber
A barber is someone whose occupation is to cut any type of hair, and to shave or trim the beards of men. The place of work of a barber is generally called a barbershop....
shops, and day spa
Day spa
A day spa is a business establishment which people visit for professionally administered personal care treatments such as massages and facials. It is similar to a beauty salon in that it is only visited for the duration of the treatment. Day spas sited in airport terminals are often called airport...
s, and products are available commercially for home use. Laser hair removal and electrolysis
Electrology
Electrology is the practice of electrical epilation to permanently remove human hair. The actual process of removing the hair is referred to as electrolysis.-Overview:...
are also available, though these are provided (in the US) by licensed professionals in medical offices or speciality spas.
Biological processes and hygiene
Hair follicle
A hair follicle is a skin organ that produces hair. Hair production occurs in phases, including a growth phase , and cessation phase , and a rest phase . Stem cells are principally responsible for the production of hair....
, hair root, root sheath
Root sheath
The inner or epidermic coat of the hair follicle is closely adherent to the root of the hair, and consists of two strata named respectively the outer and inner root sheaths;-Outer Root Sheath:...
, and sebaceous gland
Sebaceous gland
The sebaceous glands are microscopic glands in the skin that secrete an oily/waxy matter, called sebum, to lubricate and waterproof the skin and hair of mammals...
) are beneath the skin, while the actual hair shaft which emerges (the cuticle
Cuticle
A cuticle , or cuticula, is a term used for any of a variety of tough but flexible, non-mineral outer coverings of an organism, or parts of an organism, that provide protection. Various types of "cuticles" are non-homologous; differing in their origin, structure, function, and chemical composition...
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
Cuticle
A cuticle , or cuticula, is a term used for any of a variety of tough but flexible, non-mineral outer coverings of an organism, or parts of an organism, that provide protection. Various types of "cuticles" are non-homologous; differing in their origin, structure, function, and chemical composition...
remains intact.
Scalp skin, just like any other skin on the body, must be kept healthy to ensure a healthy body and healthy hair production. If the scalp is not cleaned regularly, by the removal of dead skin cells, toxins released through the skin or external hazards (such as bacteria, viruses, and chemicals) may create a breeding ground for infection. However, not all scalp disorders are a result of bacterial infections. Some arise inexplicably, and often only the symptoms can be treated for management of the condition (example: dandruff
Dandruff
Dandruff is the shedding of dead skin cells from the scalp . Dandruff is sometimes caused by frequent exposure to extreme heat and cold. As it is normal for skin cells to die and flake off, a small amount of flaking is normal and common; about 487,000 cells/cm2 get released normally after...
). There are also bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
that can affect the hair itself. Head lice is probably the most common hair and scalp ailment worldwide. Head lice can be removed with great attention to detail, and studies show it is not necessarily associated with poor hygiene. More recent studies reveal that head lice actually thrive in clean hair. In this way, hair washing as a term may be a bit misleading, as what is necessary in healthy hair production and maintenance is often simply cleaning the surface of the scalp skin, the way the skin all over the body requires cleaning for good hygiene.
The sebaceous gland
Sebaceous gland
The sebaceous glands are microscopic glands in the skin that secrete an oily/waxy matter, called sebum, to lubricate and waterproof the skin and hair of mammals...
s in human skin produce sebum, which is composed primarily of fatty acid
Fatty acid
In chemistry, especially biochemistry, a fatty acid is a carboxylic acid with a long unbranched aliphatic tail , which is either saturated or unsaturated. Most naturally occurring fatty acids have a chain of an even number of carbon atoms, from 4 to 28. Fatty acids are usually derived from...
s. Sebum acts to protect hair and skin, and can inhibit the growth of microorganisms on the skin. Sebum contributes to the skin’s slightly acidic natural pH
PH
In chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...
somewhere between 5 and 6.8 on the pH spectrum. This oily substance gives hair moisture and shine as it travels naturally down the hair shaft, and serves as a protective substance preventing the hair from drying out or absorbing excessive amounts of external substances. Sebum is also distributed down the hair shaft “mechanically” by brushing and combing. When sebum is present in excess, the roots of the hair can appear oily, greasy, and darker than normal, and the hair may stick together.
Hair cleaning
One way to distribute the hair's natural oils through the hair is by brushing with a natural bristle brush. The natural bristles effectively move the oil from the scalp through to the hair's mid-lengths and ends, nourishing these parts of the hair. Brushing the scalp also stimulates the sebaceous gland, which in turn produces more sebum. When sebum and sweat combine on the scalp surface, they help to create the acid mantleAcid mantle
The acid mantle is a very fine, slightly acidic film on the surface of the skin acting as a barrier to bacteria, viruses and other potential contaminants that might penetrate the skin. The pH of the skin is between 4.5 and 6.2, so it is acidic...
, which is the skin's own protective layer.
Washing hair removes excess sweat and oil, as well as unwanted products from the hair and scalp. Often hair is washed as part of a shower
Shower
A shower is an area in which one bathes underneath a spray of water.- History :...
or bathing
Bathing
Bathing is the washing or cleansing of the body in a fluid, usually water or an aqueous solution. It may be practised for personal hygiene, religious ritual or therapeutic purposes or as a recreational activity....
with shampoo
Shampoo
Shampoo is a hair care product used for the removal of oils, dirt, skin particles, dandruff, environmental pollutants and other contaminant particles that gradually build up in hair...
, a specialized surfactant. Shampoos work by applying water and shampoo to the hair. The shampoo breaks the surface tension of the water, allowing the hair to become soaked. This is known as the wetting action. The wetting action is caused by the head of the shampoo molecule attracting the water to the hair shaft. Conversely, the tail of the shampoo molecule is attracted to the grease, dirt and oil on the hair shaft. The physical action of shampooing makes the grease and dirt become an emulsion that is then rinsed away with the water. This is known as the emulsifying action.
Shampoos have a pH of between 4 and 6 and do not contain soap. Soapless shampoos are acidic and therefore closer to the natural pH of hair. Acidic shampoos are the most common type used and maintain or improve the condition of the hair as they don't swell the hairshaft and don't strip the natural oils.
Conditioners are often used after shampooing to smooth down the cuticle layer of the hair, which can become roughened during the physical process of shampooing. There are three main types of conditioners: anti-oxidant conditioners, which are mainly used in salons after chemical services and prevent creeping oxidation; internal conditioners, which enter into the cortex of the hair and help improve the hair's internal condition (also known as treatments); and external conditioners, or everyday conditioners, which smooth down the cuticle layer, making the hair shiny, combable and smooth. Conditioners can also provide a physical layer of protection for the hair against physical and environmental damage.
Hairstyling tools
Hairstyling equipmentHair styling equipment which helps in creating hairstyles includes:
|
Hair productsCosmeticsCosmetics Cosmetics are substances used to enhance the appearance or odor of the human body. Cosmetics include skin-care creams, lotions, powders, perfumes, lipsticks, fingernail and toe nail polish, eye and facial makeup, towelettes, permanent waves, colored contact lenses, hair colors, hair sprays and... products used in creating and maintaining hairstyles include:
|
Hair lengths
Hairstyle — hair on head human, Arranged in a certain way, perhaps using Combs, Dryer, gel etc. Is the end product Hairdressing.- Bald - having no hair at all on the head
- ShaveShaveShave may refer to:*to shave refers to the act of shaving*"Shave," a song by Enon from their 2003 album Hocus Pocus*Shave , a periodical magazine...
d - hair that is completely shaved down to the scalpScalpThe scalp is the anatomical area bordered by the face anteriorly and the neck to the sides and posteriorly.-Layers:It is usually described as having five layers, which can conveniently be remembered as a mnemonic:... - BuzzBuzz cutA buzz cut, induction cut or wiffle is a very short haircut.The cut is usually performed using hair clippers without a comb guard. The sides are cut closely and then the top is either shaped or cut to the same short length all over. The cut takes just a few minutes to perform. A buzz cut can...
- hair that is extremely short and hardly there - CroppedCrop (hairstyle)A crop is a short hairstyle worn with the hair cut very close to the head. It is frequently sported by both men and women, though the style is usually only named as a crop when sported by a woman. Men entering the armed forces in many countries have their hair cropped during Recruit Training...
- hair that is a little longer than a buzz - Boy's cut - hair that is longer than a crop, but not yet hits the earsEARSEARS may refer to:* Electoral software* Electronic Arts, Redwood Shores campus.* Emirates Amateur Radio Society...
- Ear length - hair up to one's ears
- Chin level - hair grows down to the chin
- Flip level - hair reaching the neck or shoulders
- Shoulder length - hair reaching the shoulders
- Armpit length - hair reaching the armpit
- Midback level - hair that's at about the same point as the widest part of one's ribcage and chestChestThe chest is a part of the anatomy of humans and various other animals. It is sometimes referred to as the thorax or the bosom.-Chest anatomy - Humans and other hominids:...
area - Waist length - hair that falls at the smallest part of one's waistWaistThe waist is the part of the abdomen between the rib cage and hips. On proportionate people, the waist is the narrowest part of the torso....
, a little bit above the hip bones - Hip length - hair reaching the top of one's hips
- Tailbone length - hair that is at about the area of one's tailbone
- Classic length - hair that reaches where one's legsHuman legThe human leg is the entire lower extremity or limb of the human body, including the foot, thigh and even the hip or gluteal region; however, the precise definition in human anatomy refers only to the section of the lower limb extending from the knee to the ankle.Legs are used for standing,...
meet his or her buttocksButtocksThe buttocks are two rounded portions of the anatomy, located on the posterior of the pelvic region of apes and humans, and many other bipeds or quadrupeds, and comprise a layer of fat superimposed on the gluteus maximus and gluteus medius muscles. Physiologically, the buttocks enable weight to... - Thigh length - hair that is at the mid-thigh
- Knee-length - hair that is at the kneeKneeThe knee joint joins the thigh with the leg and consists of two articulations: one between the fibula and tibia, and one between the femur and patella. It is the largest joint in the human body and is very complicated. The knee is a mobile trocho-ginglymus , which permits flexion and extension as...
- Calf length - hair that is at the calfCalf (anatomy)In human anatomy the calf is the back portion of the lower leg . In terms of muscle systems, the calf corresponds to the posterior compartment of the leg. Within the posterior compartment, the two largest muscles are known together as the calf muscle and attach to the heel via the Achilles tendon...
- Floor length - hair that reaches the floor
Chemical alteration
Chemical alterations like perming, coloring can be carried out to change the perceived quality and texture of hair. All of these are temporary alterations because permanent alterations are not possible.Chemical alteration of hair only affects the hair above the scalp; unless the hair roots are damaged, new hair will grow in with natural color and texture.
Hair coloring
Hair coloringHair coloring
Hair coloring is the practice of changing the color of hair. Common reasons are to cover gray hair, to change to a color regarded as more fashionable or desirable, and to restore the original hair color after it has been discolored by hairdressing processes or sun bleaching...
is the process of adding pigment to or removing pigment from the hair shaft. Hair coloring processes may be referred to as coloring or bleaching, depending on whether you are adding or removing pigment.
Temporary hair tints simply coat the shaft with pigments which later wash off.
Most permanent color changes require that the cuticle of the hair be opened so the color change can take place within the cuticle. This process, which uses chemicals to alter the structure of the hair, can damage the cuticle or internal structure of the hair, leaving it dry, weak, or prone to breakage. After the hair processing, the cuticle may not fully close, which results in coarse hair or an accelerated loss of pigment. Generally, the lighter the chosen colour from one's initial hair color, the more damaged it may be. Other options for applying color to hair besides chemical dyes include the use of such herbs as henna
Henna
Henna is a flowering plant used since antiquity to dye skin, hair, fingernails, leather and wool. The name is also used for dye preparations derived from the plant, and for the art of temporary tattooing based on those dyes...
and indigo
Indigofera
Indigofera is a large genus of about 700 species of flowering plants belonging to the family Fabaceae.The species are mostly shrubs, though some are herbaceous, and a few can become small trees up to tall. Most are dry-season or winter deciduous. The leaves are pinnate with 5–31 leaflets and the...
, or choosing ammonia-free solutions.
Perms and chemical straightening
Perms and relaxation using relaxerRelaxer
A relaxer is a type of lotion or cream generally used by people with afro textured hair, which makes hair less curly and also easier to straighten by chemically "relaxing" the natural curls...
or thermal reconditioning involve chemical alteration of the internal structure of the hair in order to affect its curliness or straightness.
Hair that has been subjected to the use of a permanent is weaker due to the application of chemicals, and should be treated gently and with greater care than hair that isn't chemically altered.
Environmental factors
Minerals in water can affect hair.Calcium causes hair to feel dry and lack shine and volume. It can prevent the proper processing of color, highlights, perms or relaxer/straighteners and can cause a perm to appear relaxed. Calcium builds up on the scalp causing flaking of the scalp, giving the appearance of dandruff. Calcium can choke the hair at the mouth of the follicle causing the hair to break off, then coat the scalp, blocking further new hair growth.
Iron can cause water to have a red or rusty hue. Iron leaves hair feeling dry, brittle and weighted down. It causes lack of shine and can cause dark hair to tint darker and blonde hair to turn orange. Iron can inhibit the proper processing of perms, color, highlights, and relaxers/straighteners
Copper discolors hair causing blonde hair to turn green and dark hair to tint darker. Copper can weigh hair down and cause dryness, and can inhibit the proper processing of perms, color, highlights, and relaxers/straighteners.
Magnesium causes hair to lack shine, feel dry, appear weighted down therefore lacking volume, and can inhibit the proper processing of perms, color, highlights, and relaxers/straighteners.
Silica causes many of the same effects on the hair as calcium. It causes hair to feel dry, lack volume, and can cause dandruff-like symptoms of flaking. Build-up of silica can choke the hair follicle causing hair to fall out.
Lead can cause the hair to feel dry. Lead can prevent the proper processing of perms, color, highlights, and relaxers/straighteners.
Typically, these minerals can be found in groundwater
Groundwater
Groundwater is water located beneath the ground surface in soil pore spaces and in the fractures of rock formations. A unit of rock or an unconsolidated deposit is called an aquifer when it can yield a usable quantity of water. The depth at which soil pore spaces or fractures and voids in rock...
usually extracted using a well
Water well
A water well is an excavation or structure created in the ground by digging, driving, boring or drilling to access groundwater in underground aquifers. The well water is drawn by an electric submersible pump, a trash pump, a vertical turbine pump, a handpump or a mechanical pump...
. The level of calcium that is found naturally from the ground determines the hardness of water. While calcium is the element that determines hardness of water, there are many other elements in well water that affect hair, scalp and skin.
To improve the hair health and further prevent issues with dryness and buildup, people can use a shower head filter that will remove the minerals found in most city waters. However, hard water minerals and the sanitizing agents like Chlorine and Chloramine can also deposit in or on the hair, building up over time. The chemical and mineral content of water varies by geography. Filtering water through very fine mesh cloth may help to remove larger deposits in the water. Many enjoy collecting rain water, although acid rain is an increasing issue in many parts of the world.
Treatment for well water and hard water conditions are available in a variety of products, such as demineralizing shampoos and conditioners.
Those who swim in chlorinated or salt sea water may benefit from first wetting the hair entirely and then applying conditioner to completely swell the entire hair shaft. Swimmers may also benefit from products on the market that remove chlorine after swimming in pool water.
Long hair
Many industries have requirements for hair being contained to prevent worker injury. This can include people working in construction, utilities, and machine shops of various sorts. Furthermore, many professions require containing the hair for reasons of public health, and a prime example is the food industry. There are also sports that may require similar constraints for safety reasons: to keep hair out of the eyes and blocking one's view, and to prevent being caught in sports equipment or trees and shrubs, or matted hair in severe weather conditions or water. Safety is usually the reason behind not allowing hair to fly loose on the backs of motorcycles and open-topped sports cars for longer tresses.Delicate skin
Scalp skin of babies and the elderly are similar in subdued sebaceous gland production, due to hormonal levels. The sebaceous gland secretes sebum, a waxy ester, which maintains the acid mantle of the scalp and provides a coating that keeps skin supple and moist. The sebum builds overly, between every 2–3 days for the average adult. Those with delicate skin may experience a longer interval. Teenagers often require daily washing of the hair. Sebum also imparts a protective coating to hair strands. Daily washing will remove the sebum daily and incite an increase in sebum production, because the skin notices the scalp skin is lacking sufficient moisture. In cases of scalp disorders, however, this may not be the case. For babies and elderly, the sebaceous gland production is not at peak, thus daily washing is not typically needed.Split ends
Split endsSplit Ends
-TV:*Split Ends , a sitcom produced on ITV*Split Ends , a reality show on Style Network-Other:* split ends, the splitting or fraying of hair — see Trichoptilosis...
, 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
Heat
In physics and thermodynamics, heat is energy transferred from one body, region, or thermodynamic system to another due to thermal contact or thermal radiation when the systems are at different temperatures. It is often described as one of the fundamental processes of energy transfer between...
, that weathers the hair may eventually lead to split ends. Typically, the damaged hair fiber splits into two or three strands and the split may be 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.
As hair grows, the natural protective oils of the scalp
Scalp
The scalp is the anatomical area bordered by the face anteriorly and the neck to the sides and posteriorly.-Layers:It is usually described as having five layers, which can conveniently be remembered as a mnemonic:...
can fail to reach the ends of the hair. The ends are considered old once they reach about 10 centimeters since they have had long exposure to the sun, gone through many shampoos and may have been overheated by hair dryers and hot irons. This all results in dry, brittle ends which are prone to splitting
Split Ends
-TV:*Split Ends , a sitcom produced on ITV*Split Ends , a reality show on Style Network-Other:* split ends, the splitting or fraying of hair — see Trichoptilosis...
. Infrequent trims and lack of hydrating treatments can intensify this condition.
Breakage and other damage
Hair can be damaged by chemical exposure, prolonged or repeated heat exposure (as through the use of heat styling tools), and at times by excessive perming and straighteningHair straightening
Hair straightening is a hair styling technique which involves the flattening and straightening of hair in order to give it a smooth, streamlined, and 'sleek' appearance. It may be accomplished by using hair irons and hot combs, chemical relaxers, Japanese hair straightening, or Brazilian hair...
.
Infections and skin disorders
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 alopeciaAlopecia
Alopecia means loss of hair from the head or body. Alopecia can mean baldness, a term generally reserved for pattern alopecia or androgenic alopecia. Compulsive pulling of hair can also produce hair loss. Hairstyling routines such as tight ponytails or braids may induce Traction alopecia. Both...
, hair pulling/picking, hair that sticks straight out, black dots on the hair, and rashes or burns resulting from chemical processes.
There are a number of disorders that are particular to the scalp. Symptoms may include:
- Abnormal odor
- Bleeding
- Bumps
- Caking skin buildup that appears white or another color than one's natural skin tone
- Chafes
- Clumps of hair falling out
- Clumpy flakes that do not easily slough off the scalp skin
- DandruffDandruffDandruff is the shedding of dead skin cells from the scalp . Dandruff is sometimes caused by frequent exposure to extreme heat and cold. As it is normal for skin cells to die and flake off, a small amount of flaking is normal and common; about 487,000 cells/cm2 get released normally after...
- Excessive itchiness that doesn't go away with a few hair wash, redness of scalp skin
- Patches of thinning
- Pus-like drainage
- Shedding
Any of these symptoms may indicate a need for professional assistance from a dermatologist or trichologist for diagnosis.
Scalp skin can suffer from infestations of mites, lice, infections of the follicles or fungus. There could be allergic reactions to ingredients in chemical preparations applied to the hair, even ingredients from shampoo or conditioners. Common concerns surrounding dandruff (often associated with excessive sebum); psoriasis, eczema, or seborrheic dermatitis.
An odor that persists for a few weeks despite regular hair washing may be an indication of a health problem on the scalp skin.
Not all flakes are dandruff. For example, some can merely be product buildup on the scalp skin. This could result from the common practice of applying conditioner to scalp skin without washing. This would dry upon the scalp skin and flake off, appearing like dandruff and even causing itchiness, but have no health effects whatsoever.
Hormone changes and imbalances
There are various reasons for hair loss, most commonly hormonal issues. Fluctuations in hormones will often show in the hair. Not all hair loss is related to what is known as male pattern baldness, women can suffer from baldness just as men do. Formulas for addressing this specific cause of lack of hair growth yet typically they require around three months of consistent use for results to begin to appear. Cessation may also mean that gained growth may dissipate.Particularly among women, thyroid disease is one of the more under-diagnosed health concerns. Hair falling out in clumps is one symptom of a set of symptoms that may indicate a thyroid concern. In many gynecological exams a blood screen for thyroid is now a common protocol. Thyroid often shows up first in the behavior of the hair.
During pregnancy and breast feeding, the normal and natural shedding process is typically suspended (starting around month three because it takes a while for the body to recognize and reset for the hormonal shifts the body goes through) for the period of gestation and extended longer if one breast feeds (this includes pumping for breast milk). Upon cessation of either of these, it typically takes around two months for the hormones to shift again to the normal hormonal settings, and hair shedding can increase exponentially, for approximately 3–6 months until hair returns to its normal volume. It is commonly noticed that hair seems thicker and shinier, even, during pregnancy and breast feeding in response to the influx of shifting hormones. It is not unusual also for hair color to change, or hair structure to change (e.g., straighter hair, curlier hair). These changes can occur more often than people may realize yet isn't often reported.
General hair loss
Some choose to shave their hair off entirely, while still others may have an illness (such as a form of cancer—note that not every form of cancer or cancer treatment necessarily means one will lose their hair) that caused hair loss or lead to a decision to shave the head.Preventive action – nutrition
Genetics and health are factors in healthy hair. Proper nutritionNutrition
Nutrition is the provision, to cells and organisms, of the materials necessary to support life. Many common health problems can be prevented or alleviated with a healthy diet....
is important for hair health. The living part of 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 vein, 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.
Generally, eating a full diet that contains protein, fruits, vegetables, grains, and even an appropriate amount of fat is important (several vitamins and minerals require fat in order to be delivered or absorbed by the body). Any deficiency will typically show first in the hair. A mild case of anemia
Anemia
Anemia is a decrease in number of red blood cells or less than the normal quantity of hemoglobin in the blood. However, it can include decreased oxygen-binding ability of each hemoglobin molecule due to deformity or lack in numerical development as in some other types of hemoglobin...
can cause shedding and hair loss. Among others, the B group of vitamins are the most important for healthy hair, especially biotin. B5 (pantothenic Acid) gives hair flexibility, strength and shine and helps prevent hair loss and graying. B6 helps prevent dandruff and can be found in cereals, egg yolk and liver. Vitamin B12 helps prevent the loss of hair and can be found in fish, eggs, chicken and milk.
When the body is under strain, it reprioritizes its processes. For example, the vital organs will be attended to first, meaning that healthy, oxygenated blood may not feed into the hair follicle, resulting in less healthy hair or a decline in growth rate. While not all hair growth issues stem from malnutrition, it is a valuable symptom in diagnosis.
Scalp hair grows, on average, at a rate of about half an inch per month, and shampoos or vitamins have not been shown to noticeably change this rate. Hair growth rate also depends upon what phase in the cycle of hair growth one is actually in; there are three phases. The speed of hair growth varies based upon genetics
Genetics
Genetics , a discipline of biology, is the science of genes, heredity, and variation in living organisms....
, gender
Gender
Gender is a range of characteristics used to distinguish between males and females, particularly in the cases of men and women and the masculine and feminine attributes assigned to them. Depending on the context, the discriminating characteristics vary from sex to social role to gender identity...
, age, hormones, and may be reduced by nutrient
Nutrient
A nutrient is a chemical that an organism needs to live and grow or a substance used in an organism's metabolism which must be taken in from its environment. They are used to build and repair tissues, regulate body processes and are converted to and used as energy...
deficiency (i.e., anorexia, anemia, zinc deficiency) and hormonal fluctuations (i.e., menopause, polycystic ovaries, thyroid disease).
The essential omega-3 fatty acids, protein
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
, vitamin B12
Vitamin B12
Vitamin B12, vitamin B12 or vitamin B-12, also called cobalamin, is a water-soluble vitamin with a key role in the normal functioning of the brain and nervous system, and for the formation of blood. It is one of the eight B vitamins...
, and iron
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...
, found in fish sources, prevent a dry scalp and dull hair color. Dark green vegetables contain high amounts of vitamins A and C, which help with production of sebum and provide a natural hair conditioner. Legumes provide protein to promote hair growth and also contain iron, zinc
Zinc
Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2...
, and biotin. Biotin
Biotin
Biotin, also known as Vitamin H or Coenzyme R, is a water-soluble B-complex vitamin discovered by Bateman in 1916. It is composed of a ureido ring fused with a tetrahydrothiophene ring. A valeric acid substituent is attached to one of the carbon atoms of the tetrahydrothiophene ring...
functions to activate certain enzymes that aid in metabolism of carbon dioxide as well as protein, fats, and carbohydrates. A deficiency in biotin intake can cause brittle hair and can lead to hair loss. In order to avoid a deficiency, individuals can find sources of biotin in cereal-grain products, liver, egg yolk, soy flour, and yeast. Nuts contain high sources of selenium
Selenium
Selenium is a chemical element with atomic number 34, chemical symbol Se, and an atomic mass of 78.96. It is a nonmetal, whose properties are intermediate between those of adjacent chalcogen elements sulfur and tellurium...
and therefore are important for a healthy scalp. Alpha-linoleic acid and zinc are also found in some nuts and help condition the hair and prevent hair shedding that can be caused by a lack of zinc. Protein deficiencies or low-quality protein can produce weak and brittle hair, and can eventually result in loss of hair color. Low-fat dairy products are good sources of calcium
Calcium
Calcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust...
, a key component for hair growth. A balanced diet is extremely necessary for a healthy scalp and furthermore healthy hair.
See also
- Hair coloringHair coloringHair coloring is the practice of changing the color of hair. Common reasons are to cover gray hair, to change to a color regarded as more fashionable or desirable, and to restore the original hair color after it has been discolored by hairdressing processes or sun bleaching...
- Hair conditionerHair conditionerHair conditioner is a hair care product that alters the texture and appearance of hair.-History:For centuries, natural oils have been used to condition human hair. These natural products are still used today, including essential oils such as tea tree oil and carrier oils such as jojoba oil...
- Hair gelHair gelHair gel is a hairstyling product that is used to stiffen hair into a particular hairstyle. The results it produces are usually similar to, but stronger than, those of hair spray and hair wax, and weaker than those of hair glue.-Types:...
- Hair mousseHair mousseHair mousse is a hairstyling product added to hair for extra volume and shine. It is often dispensed in an aerosol foam spray or in a cream form. Hair mousse adds volume to hair and often provides both conditioning and hold, without any clumps or buildup. Hair mousse is a purple color while in the...
- Hair transplantationHair transplantationHair transplantation is a surgical technique that involves moving individual hair follicles from one part of the body to bald or balding parts . It is primarily used to treat male pattern baldness. It this case, grafts containing hair follicles that are genetically resistant to balding are...
- Hair washingHair washingHair washing is the cosmetic act of keeping hair clean by washing it with shampoo or other detergent products and water. Hair conditioner may also be used to improve hair's texture and manageability...
- ShampooShampooShampoo is a hair care product used for the removal of oils, dirt, skin particles, dandruff, environmental pollutants and other contaminant particles that gradually build up in hair...
- StubbleStubbleStubble is the regrowth of shaven hair, when it is short and has a rough, abrasive texture.-Facial:During the 1980s, facial stubble on men became fashionable, partly due to being popularized by the singer George Michael, as well as Miami Vice. This was also known as designer stubble and was...
- the regrowth of shaven hair on the face, legs, armpits or chest that is short and rough to the touch - Madam C. J. Walker
External links
- How to Wash Your Hair Without Shampoo - a wiki article on cleaning hair without shampoo.