Acne
Acne Vulgaris is an inflammatory disease of the skin, caused by changes in the pilosebaceous units (skin structures consisting of a hair follicle and its associated sebaceous gland). Acne lesions are commonly referred to as pimples, spots, or zits.
Acne develops as a result of blockages in follicles. Hyperkeratinization and formation of a plug of keratin and sebum (a microcomedo) is the earliest change. Enlargement of sebaceous glands and an increase in sebum production occur with increased androgen (DHEA-S) production at adrenarche. Increased sebum production provides an environment for the overgrowth of Propionibacterium acnes. Bacterial overgrowth of Propionibacterium acnes can cause inflammation.
The condition is most common during adolescence, affecting more than 85% of teenagers, but frequently continues into adulthood For most people, acne diminishes over time and tends to disappear, or at least decrease, after one reaches his or her early twenties. There is, however, no way to predict how long it will take for it to disappear entirely, and some individuals will continue to suffer from acne decades later, into their thirties and forties and even beyond
The term acne comes from a corruption of the Greek άκμή (acme in the sense of a skin eruption) in the writings of Aėtius Amidenus. The vernacular term bacne or backne is often used to indicate acne found specifically on one's back.
Causes of acne
There are many misconceptions and rumours about acne. Exactly why some people get acne and some do not is not fully known. It is known to be partly hereditary. Several factors are known to be linked to acne:
* Family history
* Hormonal activity, such as menstrual cycles and puberty
* Stress, through increased output of hormones from the adrenal (stress) glands.
* Hyperactive sebaceous glands, secondary to the three hormone sources above.
* Accumulation of dead skin cells.
* Bacteria in the pores, to which the body becomes 'allergic'.
* Skin irritation or scratching of any sort will activate inflammation.
* Use of anabolic steroids.
* Any medication containing halogens (iodides, chlorides, bromides), lithium, barbiturates, or androgens.
* Exposure to high levels of chlorine compounds, particularly chlorinated dioxins, can cause severe, long-lasting acne, known as Chloracne.
Traditionally, attention has focused mostly on hormone-driven over-production of sebum as the main contributing factor of acne. More recently, more attention has been given to narrowing of the follicle channel as a second main contributing factor. Abnormal shedding of the cells lining the follicle, abnormal cell binding ("hyperkeratinization") within the follicle, and water retention in the skin (swelling the skin and so pressing the follicles shut) have all been put forward as important mechanisms. Several hormones have been linked to acne: the male hormones testosterone, dihydrotestosterone (DHT) and dehydroepiandrosterone sulfate (DHEAS), as well as insulin-like growth factor 1 (IGF-I). In addition, acne-prone skin has been shown to be insulin resistan.
Development of acne vulgaris in later years is uncommon, although this is the age group for Rosacea which may have similar appearances. True acne vulgaris in adults may be a feature of an underlying condition such as pregnancy and disorders such as polycystic ovary syndrome or the rare Cushing's syndrome. Dermatologists are seeing more cases of menopause-associated acne as fewer women replace the natural anti-acne ovarian hormone estradiol whose production fails as women arrive at menopause. The lack of estradiol also causes thinning hair, hot flashes, thin skin, wrinkles, vaginal dryness, and predisposes to osteopenia and osteoporosis as well as triggering acne (known as acne climacterica in this situation).
Traditional Chinese Medicine philosophy is based around the idea that illness is a form of imbalance, and acne is no exception. One idea is that the body of the patient contains a lot of "hot" energy, and may be due to diet (e.g. fried foods, chocolate, lychee, durian) or an imbalanced life style (this may be connected with hormone activity). The usual treatment is to assume a healthy life style, and that the patient should eat food that is "cool" by nature, such as some herbal teas, and certain fruits, e.g. melons
Diet
There is no widely agreed-upon proof that diet has any effect on most people's acne. Eating greasy foods, however, may get grease on a person's hands. Subsequent contact of the hands to the face may exacerbate acne.
Milk
A recent study, based on a survey of 47,335 women, did find a positive epidemiological association between acne and consumption of partially skimmed milk, instant breakfast drink, sherbet, cottage cheese and cream cheese The researchers hypothesize that the association may be caused by hormones (such as several sex hormones and bovine IGF-I) present in cow milk. Although the association between milk and acne has been definitively shown, the ingredient in the milk responsible for the acne is still unclear. Most dermatologists are awaiting confirmatory research linking diet and acne but some support the idea that acne sufferers should experiment with their diets, and refrain from consuming such fare if they find such food affects the severity of their acne
Seafood
Seafood often contains relatively high levels of iodine. Iodine is known to make existing acne worse but there is probably not enough to cause an acne outbreak Still, people who are prone to acne may want to avoid excessive consumption of foods high in iodine.
High carbohydrates/High GI
It has also been suggested that there is a link between a diet high in refined sugars and other processed foods and acne. According to this hypothesis, the startling absence of acne in non-westernized societies could be explained by the low glycemic index of these cultures' diets. Others have cited possible genetic reasons for there being no acne in these populations, but similar populations shifting to these diets do develop acne Note also that the populations studied consumed no milk or other dairy products Further research is necessary to establish whether a reduced consumption of high-glycemic foods (such as soft drinks, sweets, white bread) can significantly alleviate acne, though consumption of high-glycemic foods should in any case be kept to a minimum, for general health reasons Avoidance of 'junk food' with its high fat and sugar content is also recommended On the other hand there is no evidence that fat alone makes skin oilier or acne worse.
One study suggested that chocolate, french fries, potato chips and sugar, among others, affect acne. A high GI (glycemic index) diet that causes sharp rises in blood sugar worsens acne. If this study's conclusions are verified then a low GI diet may help acne also, but a 2005 review of somewhat dated scientific literature cannot affirm either way A study in November 2006 in Australia gave a 50% reduction in 12 weeks in mild-moderate facial acne by introducing its subjects to a high protein, low GI diet
Hygiene
Deficient personal hygiene. Acne is not caused by dir. This misconception probably comes from the fact that blackheads look like dirt stuck in the openings of pores. The black color is simply not dirt but compact kerati. In fact, the blockages of keratin that cause acne occur deep within the narrow follicle channel, where it is impossible to wash them away. These plugs are formed by the failure of the cells lining the duct to separate and flow to the surface in the sebum created there by the body.
Sex
Common myths state that masturbation causes acne and, conversely, that celibacy or sexual intercourse can cure it. Though it has been widely accepted that these are not true due to lack of scientific study on the subject, it is also important to note sexual activity has been observed to result in hormonal spikes, which has been linked to acne.