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Module: 2

Causes

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2.1 Causes – Hormones

2.2 Causes – Diet

2.3 Causes – Lifestyle

2.4 Causes – Genetics

2.1 Causes – Hormones

Hormones have a huge part to play in the production of acne.

In section 1.1.1 we covered two potential reasons for cells clogging the follicle, and thus causing acne.

These were 1. the production of too many skin cells, and 2. hyperkeratinization. Researchers suspect

that hormones are involved in keratin levels, and hormones are known the control the rate of skin cell

growth.

In this section we’ll examine one of the main culprits in causing acne, testosterone, and look at many

different hormonal influences that can cause breakouts.

2.1.1 Testosterone and DHT

Testosterone is a natural hormone that is found in the bodies of both men and women. The average

adult male has between 4 times to 75 times more testosterone than the average adult female. This

hormone is essential for sexual behavior, building protein, bone formation, the production of blood cells,

liver function and carbohydrate metabolism. In women, it is produced in the ovaries.

DHT (Dihydrotestosterone-alpha)is a natural steroid, produced in the gonads in men. (It is also present

in women, but to a much lesser extent). It is an androgen (male) hormone, and is responsible for the

biological characteristics of males, such as increased muscle mass, hair on the chest and a deep voice.

5% of free testosterone is converted into DHT, by the 5-alpha enzyme. DHT is about five times more

potent than testosterone, and is considered a very potent androgen.

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DHT can cause acne because it over stimulates the sebaceous glands, the same oil glands that

cause your skin to product more sebum. This can result in more acne as pores become clogged.

This is not always the cause of acne, but it can be, particularly in females.

2.1.2 Periods

Women can experience menstrual acne, which is a flare up on the skin that coincides with their period.

Generally, the acne will start to be more severe around seven to 10 days before the period begins, and

will subside when bleeding starts. Around 63% of women who are acne-prone experience these flare

ups, according to a study in the Archives of Dermatology.

The reason for this is hormonal changes. In the first half of the cycle, estrogen is the main hormone,

while in the second half, progesterone is dominant. As the period approaches, the levels of both

hormones fall significantly. Testosterone stays at a constant level throughout the month, and when the

other hormones dip, it becomes dominant and makes the oil glands produce more sebum, which

increases breakouts.

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2.1.3 Pregnancy

Acne is very common during pregnancy. More than 50% of women develop some level of acne in

pregnancy. Some of these women will have had acne before pregnancy and find it gets worse, while

others will have never suffered from acne before. Women who have a history of acne or acne flares

during menstruation are more likely to suffer from acne during pregnancy.

Acne in pregnancy is mostly caused by the increased levels of hormones in the first trimester, which

increases the skin’s production of sebum. Specifically, it is the release of progesterone that causes

breakouts around the sixth week of pregnancy. If acne does not break out in the first trimester, it is

unlikely to during the second or third trimesters.

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2.1.4 Polycystic ovary syndrome

Polycystic Ovary Syndrome, also known as PCOS, is a condition caused by an imbalanced

secretion of hormones by the pituitary gland. This affects the ovaries. PCOS usually occurs when

insulin levels or luteinizing hormone levels are too high, which causes the ovaries to produce extra

testosterone.

The consequences of this imbalance include weight gain, acne, and extra hair on the face and body.

The acne and extra hair are caused because the hair follicles and skin cells are very sensitive to

even slight increases in testosterone in the body.

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2.1.6 Teenagers

Acne in teenagers begins because of a surge in hormone production.

During puberty, both girls and boys start to produce higher levels of androgen. These are the male

sex hormones, which include testosterone. The function of this hormone in boys is to stimulate the

growth and development of the testicles and penis, while in girls it is for maintaining bone and

muscle strength. This surge in testosterone sparks increased sebum production, causing breakouts.

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2.1.7 Birth control pills

Though some women use birth control pills to control their acne, some women find that birth control

actually causes acne for them, or makes existing acne worse. Contraceptives which are injected, or IUDs

(intrauterine birth control devices) can also cause acne, because of the hormones they contain.

Birth control pills contain progestin (a synthetic form of the natural hormone progesterone), estrogen or

a mixture of both. The pill that most people use is estrogen dominant, while the ‘mini pill’ contains

progestin.

When taking estrogen containing pills, acne is possible because low progesterone levels, coupled with

estrogen dominance, can cause acne. Some people, however, find their skin is cleared on these pills.

The mini pill, progesterone pills, and contraceptive implants can cause acne because of their high

progestin content, which boosts sebum production.

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2.2 Causes – Diet

The official stance of the medical profession and academia has been that there is no link between

diet and acne. This conclusion was based on a set of studies conducted in the 1970s, but now

researchers and scientists are coming forward to say that these studies were poorly designed and

executed, and that there is still much research to be done.

In this section, we’ll explore two studies which point to there being evidence of a link between diet

and acne.

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2.2.1 Cordain’s study

Scientist of health and exercise at Colorado State University, Loren Cordain PhD, conducted a study to

find out what the effect of diet was on the acne.

With an international team of researchers, he studied 1,200 in Papua New Guinea, and 115 in remote

Paraguay. This included 300 teens from Papua New Guinea and 15 in Paraguay. In two years of study,

there was not a single zit found. Cordain says that populations who eat all-natural foods do not suffer

from acne. Cordain believes this is down to diet, as the people in these studies eat only fruit, seafood,

vegetables and lean meats. They do not eat any processed or refined foods, and eat only what they grow,

gather or hunt for themselves.

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Cordain and his researchers wanted to make sure the difference in acne prevalence was not due to

genetics. To test this, they studied South Americans and New Guineans living a westernized

lifestyle, to check their acne levels. It was found that people of these ethnicities do develop acne

when they started eating an American-style diet, which indicates that it is not genetics, but rather the

diet.

But what is it about the American diet that causes acne?

Cordain noted that most of the American diet is based on high-glycemic foods, a group of foods

which includes staples such as white bread, cereals, milk, and russet potatoes. High glycemic foods

lead to a spike in blood sugar levels, which has been linked to increasing risk of cholesterol, obesity,

diabetes and other conditions. Cordain said that half of the intake of U.S. food is of high glycemic

foods, and that 85% of the grains in the western diet are highly glycemic and refined.

Cordain says that foods with a high glycemic load cause acne because of the hormone responses in our

bodies. When we consume these foods, the levels of insulin and insulin-like growth factor, IGF-1, rise. In

response, more testosterone is produced, which leads to too much sebum being produced. This can

lead to acne.

This effect is particularly pronounced in teens because, Cordain says, “The teenaged years are a time of

natural insulin resistance. The teens are growth years; for tissues to grow, they become insulin

resistant.”

Following on from his research, DrCordain created the Paleo diet for the treatment of acne, which we

will look further at in Module 4.

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2.2.2 Mann’s study

Dr. Mann, an associate professor at Royal Melbourne Institute of Technology, has also pushed against

the assumption of there being no connection between diet and acne.

Mann and his research team conducted a study on 43 young men aged between 15 and 21 years. These

men were divided into two groups, each of which was given a different diet to follow for 12 weeks:

GROUP 1 was given a diet of low glycemic foods, including whole grain pasta and breads, lean meats,

legumes, low fat dairy, fish, and lots of vegetables and fruits.

While GROUP 2 was told to eat sugary drinks and snacks, white bread and potatoes.

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After 12 weeks, the study of the young men’s acne showed some outstanding results. The boys in group

1 showed a 50% reduction in acne lesions, which is a better result than is usually seen when patients

use topical acne solutions. There were no new infections and no new lesions found.

The acne in group 2, however, was exacerbated by the diet they were following.

Mann said, “The results were astounding. And this is the first time there has ever been a proven

connection between diet and acne.”

2.3 Causes – Lifestyle

Though acne is generally not caused by minor lifestyle habits, if you are already prone to acne,

certain lifestyle choices and habits could aggravate your skin and make your acne worse.

2.3.1 Sun exposure

Opinions are divided on whether exposure to the sun improves acne or makes the condition worse.

Some sources say that short exposure to the sun (10-20 minutes per day for those of lighter complexion

and 20-30 for those of darker complexion), may help with acne symptoms. Some people with acne have

reported that getting burned causes them to break out for up to weeks afterward, as the skin has been

irritated and is working to heal itself, while others report that after a burn or tan their acne has

decreased.

Another theory which has gained support is that a vitamin D deficiency is the culprit behind the acne of

some sufferers. As vitamin D is a hormone, when it is low, it has the ability to affect other hormones in

your body, disrupting the oil production in your skin. Vitamin D also produces chemicals which reduce

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inflammation, which can improve acne, which is an inflammatory disease. This vitamin also reduces the

amount of oil released by the sebaceous glands.

Many acne sufferers have reported up to 100% healing from acne when taking a vitamin D

supplement, while others prefer to get sun exposure directly.

2.3.2 Stress

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Research has shown that acne can flare up because of stress. The Archives of Dermatology published a

Stanford University study which found that college students had flare ups of acne during exams. They

reported higher levels of stress during this time, and higher levels of acne than usual. As a result,

researchers concluded acne severity correlated strongly with higher stress levels. The results of this

study were backed up by a test of high school students in Singapore, who were found to have worse acne

during exam periods than in low stress times such as summer break.

At this stage, scientists are not entirely sure why stress makes acne worsen. The cells that produce oil do

have receptors for stress hormones, which indicates a strong link, but they are as yet unsure of exactly

how it works.

Originally it was thought that stress led to an increase in sebum production, causing more acne, but

it was found that psychological stress did not cause significantly more sebum to be produced. This

has led scientists to conclude that there definitely is a link between stress and acne, but that the

process by which stress can aggravate acne is unclear biologically.

2.3.3 Picking blemishes

Picking blemishes can make acne worse, but it is something that many people with acne find themselves

doing. Dermatologists say that when people are anxious or stressed, about their acne, or about

something else, they are more likely to make their blemishes worse by picking them.

When someone picks their blemishes extremely frequently, even compulsively, because they’re

embarrassed by and worried about their skin, they have a condition known as acne excoriee. This

compulsion to pick acne means that they create scabs on their skin, which are likely to lead to scarring.

Most kind of picking at the skin makes healing take longer and increases the risk of permanent scars. In

addition, infected debris and material can get pushed deeper into the skin, which leads to more redness

and swelling. When a pimple is popped, the skin is left open to bacteria, which can lead to infection.

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2.3.4 Over-scrubbing

Many people who have acne end up scrubbing their skin, but this can actually make the condition

worse.

It is important to remember that acne does not come from dirt. Over-washing and scrubbing the face

does nothing to decrease acne, but actually worsens it, because it increases irritation and can

compromise the protective barrier of the skin.

2.4 Causes – Genetics

2.4.1 Evidence that genes have a role to play in acne

There are many studies that illustrate that genetics has a large role to play in the development of

acne.

A study of 40 pairs of twins – 20 identical, and 20 non-identical, looked at how sebum production was

influenced by genetics. The study found that identical twins had exactly the same rates of sebum

excretion, but had different levels of acne. Non-identical twins had different levels of acne and of sebum

production. From this, it would seem that sebum production is under genetic control, but acne itself is

not.

A study of around 1000 pairs of non-identical twins, and 450 identical twins, found that genetics

accounted for around 80% of acne, while 20% could be explained by other factors like diet and stress.

In a study with around 200 acne patients and 150 people without acne, researchers found that having a

first-degree relative (child, parent or sibling) with acne, made it four times more likely you would also

suffer from acne.

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2.4.2 How genes can influence acne

As shown in section 1.5.1, genes can affect how much sebum is produced by the skin.

In addition to sebum production, genetics determine how your immune system might respond to

bacteria, which can determine whether you’ll break out or not, and how severely, under exposure to

certain bacteria. Those with acnre-prone skin have a strong inflammatory response to bacteria and

minor injuries in the skin.

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Genetics also play a role in how easily your pores become plugged and how many dead skin cells are

produced in your skin.

Another important influence genes have is over how sensitive your skin is to the hormones in your

body. Androgen hormones such as testosterone, have different effects on healthy skin as opposed

to acne-prone skin.

In people with darker complexions, acne may look less severe, because the color of the skin at least

partially hides the redness caused by inflammation. But when acne clears on darker skin it often

leaves a pinkish-brown spot, known as postinflammatory hyperpigmentation, which can stay for

months or even years.

2.4.3 Other factors

If acne runs in your family, it is likely you will suffer from it to a certain degree. But having genes that

make your skin acne-prone doesn’t mean you will automatically get acne or that there’s nothing that can

be done to prevent it or heal from it.

Many acne experts say that if you have a genetic predisposition to acne, it is likely you will have to make

lifestyle changes to prevent acne, even when other people would not. In the rest of the modules in this

course, we will be looking at various lifestyle changes and treatments that can make the difference

between suffering with acne and having clear skin.