Acne

Table of Contents

1. An Introduction To Acne
2. The Different Types Of Acne
3. How To Treat Acne
4. The Acne Blacklist: Ingredients To Avoid
5. Common Myths And Misconceptions About Acne
6. Conclusion
7. References

An Introduction To Acne

Acne is a common skin condition that is estimated to affect roughly 9.4% of the global population [1]. Often dismissed as cosmetic concern only, it is, in fact, a complex issue that can significantly impact an individual's quality of life, affecting not only their physical appearance but also their emotional well-being and self-esteem.

Acne is a skin condition not exclusive to any age group, despite the common misconception that it only affects teenagers. Many adults also struggle with acne, and an estimated 3% of adults over the age of 35 have acne [2]. However, epidemiological studies have demonstrated that acne is most common in post-pubescent teens, with boys most frequently affected, particularly with more severe forms of the disease [1].

The condition presents as spots, most commonly on the face but often on the back (accounting for over half of cases) and also on the chest (around 15%) [2]. There are 6 main types of spots:

• Blackheads – small black or yellowish bumps that develop on the skin.
• Whiteheads – similar in appearance to blackheads, but may be firmer and appear white.
• Papules – small red bumps that may feel tender or sore.
• Pustules – similar to papules, but these have a white or yellow, pus-filled tip.
• Nodules – large, hard lumps that build up beneath the surface of the skin and can be painful.
• Cysts – the most severe type of spot caused by acne; they're large pus-filled lumps that look similar to boils and carry the greatest risk of causing permanent scarring.

Understanding acne and its causes is the first step towards effective management and treatment. With the right knowledge, individuals can make informed decisions about their skincare routines and lifestyle choices, helping them to manage their acne effectively and regain their confidence.

Understanding The Different Types Of Acne

Acne Vulgaris

Acne vulgaris is the medical term for acne and also its most common form. The skin has small holes, called pores, that connect to the oil glands beneath your skin via a follicle. These glands produce an oily substance called sebum that is used to keep the skin soft and smooth. Sebum, along with a hair, passes through the follicle to reach the surface of the skin, however these pores can sometimes become blocked. Hormones called androgens, which are present in both males and females, can increase the production of sebum (oil) in the skin. This excess oil can clog pores, leading to the formation of pimples and cysts. Bacteria that normally live on the skin, called Propionibacterium acnes (P. acnes), can also become trapped in the pores and begin to multiply, leading to inflammation and the formation of pimples. The extend to which blockages in the pores occur can lead to different types of acne.

Mild-Moderate Acne

Less severe acne is caused by a small blockage of dead skin cells carried by the sebum, along with the thickening of skin at the surface of the pore. This leads to pimples, or comedones, of which there are two types. Open comedones occur when the follicle is partly blocked, and these are referred to as blackheads (due to the surface pigment, not dirt). Closed comedones arise when the follicle is completely blocked, and these are referred to as whiteheads. Sometimes, the walls of the follicle break due a large build up of sebum, and this creates a larger pimple in the form of a papule. A papule has a rough texture and is hard to the touch

Moderate - Severe Acne

Trapped sebum can provide a suitable environment for the bacterium Propionibacterium acnes to survive and multiply. This can trigger a reaction in the immune system causing inflammation and the development of pustules which are yellowish and puss-filled, often large and noticeable in appearance, and possibly painful. This can extend to small nodules which are fairly large, solid lumps, and cysts which are also large but filled with pus. Both can sometimes painful and potentially result in permanent scars.

Understanding The Different Causes Of Acne Vulgaris

There are a number of factors that can play an important role in the development of acne:

Puberty. Androgens are hormones that increase during puberty and can cause the sebaceous glands to enlarge and produce more sebum, leading to acne [3]. This is one of the main reasons why acne is common amongst teenagers.

Stress. Studies have found that an increase in stress severity strongly correlated with an increase in acne severity [4, 5].

Diet. Some studies suggest that certain foods, such as dairy products and high-glycemic-index foods, may contribute to acne [6]. However, there is limited research into this matter.

Smoking. Conflicting results, but some studies suggest there is a correlation between smoking and acne [7].

Alcohol. There is little research to suggest alcohol has a significant effect on acne [8], but it may be a contributing factor.

Menstruation. Just before your period starts, estrogen and progesterone levels drop. This can trigger your sebaceous glands to secrete more sebum. Too much can result in clogged pores and breakouts. Hormones can also increase skin inflammation and the production of acne-causing bacteria. During the menstrual cycle, there is an increase in androgen hormones, which can cause the sebaceous glands to produce more oil and lead to clogged pores [9].

Anabolic Steroids. Steroids can also cause acne due to their ability to increase androgen hormones, which can lead to increased sebum production and clogged pores [10].

Genetics. Acne can run in families, so individuals with a family history of acne may be more likely to develop it themselves [11].

Fungal Acne (Malassezia Folliculitis or Pityrosporum Folliculitis)

Despite the name, this is not actually acne, but rather a condition that can mimic the symptoms of acne. Malassezia folliculitis is caused by an overgrowth of yeast (a type of fungus) in the hair follicles [12]. The yeast, known as Malassezia, is normally present on the skin of most individuals without causing any problems. However, certain factors can cause the yeast to multiply and invade the hair follicles, leading to inflammation and the formation of small, itchy, uniform bumps on the skin [13]. These bumps can look very similar to acne, but there are a few key differences.

Unlike acne, which tends to involve a mix of different types of lesions (like blackheads, whiteheads, and inflamed pimples), Malassezia folliculitis usually involves uniform pustules that tend to be itchy, one of the main differentiating factors that makes it easier to identify. The pustules typically appear on the chest, back, and upper arms, in addition to the face. They also tend to be very itchy, which is less common with acne.

Treatment for Malassezia folliculitis is different from treatment for acne. It typically involves anti-fungal medications, either topical (applied to the skin) or oral. In contrast, acne is usually treated with anti-bacterial medications, retinoids, or hormonal therapies.

If you suspect you have fungal acne, it's important to see a dermatologist or GP for a diagnosis. They can help determine whether your symptoms are due to Malassezia folliculitis or another skin condition, and can recommend the appropriate treatment.

To learn more about Malassezia, treatments and things to avoid, see our article on seborrheic dermatitis.

Acne Mechanica

Less common than acne vulgaris, some people suffer from acne mechanica that presents with similar symptoms but is instead caused by the rubbing of the skin and hot conditions, more commonly found on athletes or soldiers, and those who also suffer from acne vulgaris. Some common causes include:

• Carrying a backpack
• Shoulder pads
• Headbands
• Chinstraps
• Tight-fitting clothes

If you’re able to identify the cause, it can be easy to prevent, for instance by wearing looser clothing or carrying a bag rather than wearing one on your back.

Acne Scarring

Acne scarring can sometimes be confused with acne itself, but is instead a common consequence of acne and can be classified into four different types: boxcar scar (BCS), rolling scar (RS), pitting scar (PS), and hypertrophic acne scar (HAS) [14]. Boxcar scars are wide, U-shaped scars with sharp edges that can be shallow or deep. Rolling scars are caused by damage under the skin and are characterized by wave-like undulations across otherwise normal-looking skin. Pitting scars, also known as "ice pick" scars, are small, deep holes in the surface of your skin that look like the skin has been punctured with a sharp object. Hypertrophic scars are thick, raised scars that are more common on the back and chest.

There are various treatments available including chemical peels, laser treatment, microneedling, and platelet-rich plasma (PRP) but it's important to note that while these treatments can significantly improve the appearance of acne scars, they may not completely eliminate scarring.

You can find out more about acne scarring here.

Skin Conditions Often Confused With Acne

Acne vs Rosacea

Acne and rosacea are both skin conditions that can cause redness and inflammation, but they have distinct differences in their causes, symptoms, and treatments. Acne is a skin condition that occurs when hair follicles become clogged with oil and dead skin cells, leading to the formation of pimples, blackheads, and whiteheads. On the other hand, rosacea is a chronic inflammatory skin condition that primarily affects the face, causing redness, visible blood vessels, and small, red, pus-filled bumps. It is most common in middle-aged women with light skin [15], though the exact cause is unknown. You can read more about rosacea here.

Acne vs Keratosis Pilaris

Keratosis pilaris is a skin condition characterised by small, rough bumps on the skin, typically on the upper arms, thighs and buttocks but sometimes on the face. These can resemble small spots but unlike acne, the condition is caused by an overproduction in keratin. Most acne treatments are ineffective for keratosis pilaris, though exfoliation can be beneficial.

Acne vs Sebaceous Hyperplasia

Both of these skin conditions are caused by an overproduction of sebum by the sebaceous glands, but there is little else in common between the two. Sebaceous hyperplasia becomes more common with age, unlike acne, and mostly affects males [16]. Trapped sebum leads to enlarged sebaceous glands, presenting as small, flesh-coloured bumps on the skin. Treatment is rarely needed as these bumps are usually harmless.

Acne vs Periorificial Dermatitis

Periorificial dermatitis is characterized by red or pink bumps around the mouth, nose and eyes that resemble small spots. They tend to be tender and sometimes itchy, and the exact cause is not well understood though is thought to be associated with products that may have come into contact with the skin. As such, treatment typically involved determining the cause and preventing contact with the skin, unlike acne.

How Acne Can Affect Mental Health

Acne may be a skin disorder, but it can also affect mental health with recent studies suggesting acne can be associated with depression and anxiety [17]. As a sufferer of acne for many years, Ryan Clarke (founder of Clever Soap) can attest to that, having struggled with low confidence and anxiety even after acne had cleared. If acne is affecting your mental health, it's important to seek help, whether through friends and family or by consulting a therapist or your GP.

How To Effectively Treat Acne

Fortunately, acne is a well-studied skin condition with a wide range of treatments available. Treatment for acne often includes topical creams and gels, oral antibiotics, and in severe cases, isotretinoin [18].

Below are a list of natural and home remedies, over the counter treatments and prescription-only medications that may help to treat acne. There are also some additional steps you can take to help improve symptoms:

Avoid overwashing. Do not wash affected areas of the skin more than twice a day, as frequent washing can irritate the skin and worsen symptoms.

Use a gentle cleanser. Wash the affected area with a gentle cleanser and lukewarm water. Avoid very hot or cold water, as it can exacerbate acne.

Hands off. Resist the urge to squeeze spots, as this can worsen symptoms and cause permanent scarring.

Choose non-comedogenic products. Avoid make-up, skincare, and suncare products that are comedogenic, as they can clog pores and worsen the condition.

Remove makeup before bed. Ensure complete removal of makeup before going to bed to prevent pore blockage.

It's important to note that acne treatments may take several months to show results, so patience is key. If you have moderate or severe acne, or if you develop nodules or cysts, it's advisable to consult a GP for proper treatment to prevent scarring.

Natural Acne Treatments

Aloe Vera. A study formulated a gel preparation of aloe vera extract and tested its anti-bacterial activity against Propionibacterium acnes. The study showed that the gel preparation of aloe vera extract did have anti-bacterial activity against Propionibacterium acnes [19], but there is limited research into it’s effectiveness.

Apple Cider Vinegar. This has natural anti-bacterial and anti-fungal properties. Diluted apple cider vinegar can be applied to the skin to help balance pH levels and control acne-causing bacteria. There is no scientific evidence to support its effectiveness in treating acne.

Charcoal. In face masks or cleansers, charcoal can help to absorb excess oils and clear out pores. This may help to reduce breakouts, but there is limited scientific evidence to support this.

Green Tea Extract. A systematic review and meta-analysis of randomized clinical trials showed that topical green tea extract application significantly reduced the inflammatory lesion counts without causing significant adverse effects, whereas oral green tea extract intake showed minimal effect [20].

Honey. Honey has been shown to have anti-oxidant and anti-bacterial properties [21], however there is limited evidence that honey is an effective treatment for acne.

Niacinamide. Sometimes known as nicotinamide, this is a form of vitamin B3 with a wide range of beneficial properties to the skin making it a popular ingredient in a number of skincare products. It is well tolerated by the skin and has been shown to help reduce sebum production [22] and reduce symptoms of mild to moderate acne [23].

Tumeric. Tumeric is commonly used as a spice that comes from the root of Curcuma longa. There is some evidence to show that, in combination with other ingredients such as galangal rhizome, another spice, it has anti-bacterial activity against acne [24].

Tea Tree Oil. A 12-week study evaluated the efficacy, tolerability, and acceptability of a tea tree oil gel (200 mg/g) and face wash (7 mg/g) for the treatment of mild to moderate facial acne. The study showed that the use of the tea tree oil products significantly improved mild to moderate acne and that the products were well tolerated [25]. Another study reported that tea tree oil at a concentration of 5% can reduce the lesions caused by acne and its bacteria [26]. Furthermore, the results of another study showed that both 5% tea tree oil and 5% benzoyl peroxide had a significant effect in ameliorating the patients' acne by reducing the number of inflamed and non-inflamed lesions, although the onset of action in the case of tea tree oil was slower. Encouragingly, fewer side effects were experienced by patients treated with tea tree oil [27].

Witch Hazel. Witch hazel is a plant native to North America and its extract is a natural astringent, meaning it can help to tighten the skin and shrink pores. With its anti-inflammatory and anti-bacterial properties, it may help to improve acne [28].

Zinc. Zinc is a naturally occurring mineral that could be an effective treatment for acne with few side effects [29]. It has anti-inflammatory properties and may help to regulate oil production, helping to manage acne [30].

Over-The-Counter Acne Treatments

Azelaic Acid. This is a dicarboxylic acid with anti-microbial and anti-inflammatory properties that can help reduce the appearance of acne [31]. In one study, it has been shown to effectively reduce the number of lesions after 12 weeks of treatment [32].

Benzyl Peroxide. One of the most common treatments for acne, benzoyl peroxide works to treat and prevent acne by killing bacteria underneath the skin, as well as helping the pores shed dead skin cells and excess sebum (oil).

Glycolic Acid. A type of alpha hydroxy acid (AHA) derived from sugar cane, it’s commonly used to exfoliate the skin and promote cell turnover. A 2019 study showed that in combination with a pulsed dyed laser it was more effective at treating acne vulgars than the laser alone [33], and a 2022 study found a 5% glycolic acid-based gel had a positive effect for the treatment of mild to moderate acne [34]. Because of its exfoliating properties and ability to promote cell turnover, it’s likely to be beneficial in helping to reduce symptoms of acne, but it can be irritating to the skin for some and cause redness, peeling and sun sensitivity so be sure to wear sunscreen and avoid prolonged exposure to the Sun when using it.

Lactic Acid. Lactic acid is another type of AHA, derived from milk. It has similar properties to glycolic acid. There is limited research into the effects on acne, with one studying demonstrating similar efficacy to salicylic acid when treating acne, although salicylic acid was more favoured by participants [35].

Resorcinol. This is a typical antiseptic agent with anti-bacterial properties, sometimes used as a treatment for acne. As a keratolytic substance, it helps to break down keratin and exfoliate the skin, unclogging the pores. There is limited data on how effective resorcinol is at treating acne.

Salicylic Acid. This is a type of beta-hydroxy acid that works by exfoliating the skin and unclogging pores [36]. In one study, salicylic acid and benzoyl peroxide showed equivalent performance in inflammatory lesion count. The benzoyl peroxide (2.5%) acne treatment regimen demonstrated an improvement over the salicylic acid (0.5%) acne treatment regimen in the non-inflammatory lesion count, but the low concentrations of salicylic acid were less drying than benzoyl peroxide and therefore salicylic acid may be better tolerated over time [37].

Sulphur. Sulfur is a chemical element that has anti-bacterial properties and can help to unclog pores and reduce inflammation. It has been used for many years to treat acne. A randomized double-blind trial compared the efficacy of three types of lotion containing sulfur in the treatment of acne vulgaris and found that the 10% sulfacetamide-sulfur lotion had the highest excellent rate and total effective rate compared to the 1% chloromycetin-sulfur lotion and 5% sulfur lotion [38].

Zinc Pyrithione. This is an anti-fungal agent with anti-bacterial and anti-microbial properties used to treat fungal conditions such as seborrheic dermatitis and fungal acne. Until 2023, it was commonly found in anti-dandruff shampoos and in a number of our products at Clever Soap, but it has since been banned in the United Kingdom and EU.

Prescription Medication For Acne

Topical Retinoids. Retinoids such as tretinoin or adapalene are a class of synthetic and naturally occurring Vitamin A compounds and derivatives that include retinol and retinoic acid, which are used in medicine and cosmetics because of their effects on skin cells. Retinoids can help treat acne by unclogging pores and reducing oil production. They can prevent dead cells from clogging pores, allowing other creams and gels to work better. The efficacy, safety, and tolerability of topical retinoids are well documented for inflammatory and non-inflammatory acne, with studies repeatedly demonstrating a decrease in the number of lesions, significant improvement in acne severity, improvement in the cosmetic appearance of acne, and the prevention of acne lesions through microcomedone formation [39].

Antibiotics. For moderate to severe cases of acne, antibiotics may be prescribed by a GP or dermatologist for treatment. They target the bacteria propionibacterium acnes, one of the main contributors to acne, and can help to reduce inflammation [40]. By inhibiting the growth of bacteria on the skin, this can help to prevent the formation of new acne lesions. However, there is an increasing reluctance to use antibiotics due to antibiotic resistance, making this treatment less popular.

Birth Control Pills. This treatment method can be very effective at treating hormonal acne, caused by a change in hormone levels. Co-cyprindiol or Yasmin/Lucette may be prescribed if over the counter treatments such as benzoyl peroxide have proved ineffective. They work by blocking the hormones that lead to a build up of sebum, thus helping to prevent acne from forming. It may take several months of taking the pill to see an improvement.

Spironolactone. Sometimes referred to by the brand name Aldactone, this type of medicine is diuretic, as well as an anti-androgen. This means it stops male hormones, such as testorone, from working [41]. A systematic review of clinical trials found that the medicine shown a significant decrease in the number of papule and total lesion count compared to a placebo [42].

Isotretinoin. Commonly known as Roaccutane, this treatment may be used for severe acne and can be prescribed by a dermatologist if other treatments have failed. The medication works by inhibiting sebaceous gland activity, reducing the amount of sebum produced, and it also has anti-inflammatory properties [43]. It is known to be the most effective form of treatment for severe acne [44], but it has been associated with a wide range of potential side effects. The most common ones include dry skin and lips, headaches, mild itching and aches and pains in muscles or joints. Some of the more serious side effects can include mood changes, severe stomach pain, muscle weakness, kidney problems, blood disorders and others [45]. Because of the potential side effects, isotretinoin is often considered a last resort for severe acne.

The Acne Blacklist: Skincare Ingredients To Avoid

You can use the following list as a guide to determine if any skincare products you use contain ingredients that could potentially aggravate acne. Most of these ingredients rank highly on the comedogenic scale, and as a general rule of thumb you want to avoid products that are considered comedogenic. However, please note that other factors should be taken into consideration, such as the concentration of said ingredients, other ingredients in the product, and the overall composition.

Emollients/Moisturizers:

• Acetylated lanolin alcohol
• Persea gratissima oil (avocado oil)
• Cetyl acetate
• Theobroma cacao seed butter (cocoa butter)
• Coconut butter
• Cocos nucifera oil (coconut oil)
• Dioctyl malate
• Dioctyl succinate
• Ethylhexyl isostearate
• Ethylhexyl palmitate
• Ethylhexyl pelargonate
• Glyceryl-3-diisostearate
• Glycine soja oil (soybean oil)
• Hydrogenated vegetable oil
• Isocetyl stearate
• Isodecyl oleate
• Isopropyl isostearate
• Isopropyl myristate
• Isopropyl palmitate
• Isostearyl neopentanoate
• Laneth-10
• Lanolin alcohol
• Myreth-3 myristate
• Myristic acid
• Myristyl lactate
• Myristyl myristate
• Octyl palmitate
• Octyl stearate
• Oleic acid
• Oleth-3
• Oleth-3 phosphate
• Oleyl alcohol
• Olea europaea oil
• Palmitic acid
• Stearyl heptanoate

Surfactants/Emulsifiers:

• Ceteareth-20
• Cetearyl alcohol
• Coal tar
• Laureth-4
• Laureth-23
• PEG 100 distearate
• PEG 100 stearate
• PEG 150 distearate
• PEG 16 lanolin
• PEG 200 dilaurate
• PEG 8 stearate

Stabilizers/Thickeners:

• Mineral oil
• Stearic acid

Debunked - Myths & Misconceptions Of Acne

Acne is caused by poor hygiene

Not true. Acne is not caused by dirt or uncleanliness. In fact, excessive washing or scrubbing can irritate the skin and make acne worse.

Eating greasy and unhealthy food can cause acne

Also not true. There is little evidence connecting food and acne.

Popping spots is a good idea

False. Squeezing pimples and blackheads can lead to additional inflammation, infection, and scarring so should be avoided.

Acne will go away on its own

Whilst many people do grow out of acne, especially once they reach adulthood, this isn’t always the case and the process can still take years. Treatment for acne can reduce symptoms, sometimes completely, in a much shorter period.

Moisturizing is bad for acne

Not true. Moisturizing is important, even for oily skin, but a non-comedogenic moisturizer is important as it won’t clog your pores and potentially worsen the condition.

Oils will make acne worse

Not always true. Some oils are non-comedogenic and won’t clog your pores. In addition, some also have anti-bacterial properties that can make them beneficial for acne.

A Final Word On Acne

To summarize, acne is a common skin condition that occurs when hair follicles become clogged with oil and dead skin cells, leading to the formation of whiteheads, blackheads, or pimples. It is most prevalent among teenagers, but can affect people of all ages. Triggers include hormonal changes, such as those occurring during puberty, certain drugs such as steroids, and comedogenic skincare products and make-up can also worsen the condition. Stress does not cause acne, but it can exacerbate the condition if it already exists.

Treatment for acne varies depending on the type and severity of acne, and the individual's willingness to commit to a treatment regimen as it may take weeks or even months before symptoms ease. For mild cases, natural and over-the-counter treatments are often effective given time. Prescription drugs are more useful for moderate acne, and in more severe cases when other treatments have proved ineffective, isotretinoin can be used as a last resort if deemed necessary by a dermatologist.

In addition to physical appearance, acne can have significant psychological impacts, including lower self-esteem and a change in mood. It can also leave physical scars, either depressions in the skin or raised scars. It’s best to treat acne early to help prevent this, and follow advice from your GP or dermatologist.

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