Acne causes are multifactorial. The exact cause of acne has never been pinpointed, and it is believed that several interrelated factors can cause acne. Perhaps it is because we often are unable to determine the root cause of acne in individuals that the statistics of this skin disease is so shocking.

The causes of adult acne and causes of cystic acne are particulary difficult to determine.

17 million people in America alone have acne. If you are between 12 and 25, you are among the 85% of people who have acne. 25% of men and 50% of women get acne during their adult lives.

The following are some of the external and internal factors that have been linked to acne in some way.

External Contributors to Acne

Makeup and skin care products

Comedogenic skin care products can cause irritation or make you break out. These include any products that clog oil ducts. Look for non-comedogenic or non-acnegenic products, but be aware these products can still make you break out.

Occupation

Depending on where you work, it is possible that your work environment can cause acne. Such environments include manufacturing or construction facilities where you may come in contact with chemicals or polluting agents that cling to the skin.

Too much sun

Evidence shows that another that exposure to sun rays is also one of many acne causes. This can even cause acne a few months after exposure.

Climate

Humidity can cause moisture in follicle cells to swell up. On the flip side, dry air can create thick sebum inside follicle cells. Both extremes can ultimately cause acne.

Picking and squeezing pimples

Touching your face or using your fingers to pick or squeeze pimples is one of the simpler acne causes that are more from habit. Picking pushes bacteria deeper into the skin cells or spread the bacteria already beneath the surface of the skin.

Sweat

Sweat trapped in by your clothing creates an ideal breeding ground for bacteria. Friction caused by leaning on or rubbing the skin or the pressure of bike helmets, backpacks, or tight collars can contribute to or worsen acne.

Internal Contributors to Acne

Bacteria

Bacteria that typically live on the skin are a contributor to acne. The bacteria known as Propionibacterium acnes are responsible for causing acne. These bacteria create enzymes that dissolve the oil in the skin, and irritate the skin causing inflammation.

Sebum production

Generally, there is a relationship between the amount of sebum produced and the severity of acne. The largest sebaceous glands are located on the face, neck, chest, upper back and upper arms.

Follicle growth

Sometimes follicle walls will grow abnormally and this can cause acne. As well, increased growth of cells can interfere with the follicles and form a plug. This plug gets bigger until it bursts and spreads bacteria on the surface of the skin.

Hormones

Many acne causes come from hormonal change or imbalance. There are hormonal changes during stress, menstruation, pregnancy, stopping/starting birth control pills, menopause, and hormonal disorders.

Androgens: Androgens are produced by the adrenal glands is one of the internal acne causes that stimulate oil glands and oil production. Increased androgen levels leads to more acne.

Stress: Although stress doesn't directly cause acne, it will aggravate it. This is because stress leads to increased androgen levels, which then affect your sebaceous glands.

Diet

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