Understanding acne and its causes

85% of adolescents and young adults are affected by acne – but acne isn’t limited to this age bracket. Millions more people worldwide, from all age brackets are affected by acne.

Women are more likely than men to experience adult acne, which affects 50% of those aged 20-29; 35% of those in their 30s; and 26% of women in their 40s.

Acne is usually caused by many contributing factors, rather than one solitary cause. This often leaves those with the condition frustrated, as it can feel impossible to identify the triggers.

The condition causes significant emotional distress – as shown by research which illustrates its link to depression, anxiety, social withdrawal and lower quality of life.

Most medications only provide temporary relief between breakouts. Testing to identify the root cause of acne empowers you with the understanding of your condition.

The anatomy of acne

There are two types of pore in your skin – sweat pores and hair follicles. Acne affects hair follicles. Part of each hair follicle includes a sebaceous gland, which produces natural oils to lubricate and waterproof your skin and hair. Certain conditions can cause your sebaceous glands to overproduce sebum, clogging the pore. Dead skin cells can mix with the sebum, adding to the clog, causing acne.

Increased skin cell growth, reduced shedding of skin cells in the hair follicle and inflammation all contribute to this process.

These conditions promote the growth of C. acnes, and other harmful bacteria that feed on sebum and dead skin cells, which leads to further inflammation.

What does acne look like?

Acne manifests in different forms and at varying severities. Recognising symptoms is the first step towards seeking help.

Comedones are the two types of non-inflammatory acne, known as blackhead and whiteheads. Blackheads are open comedones, where the contents of the pore are exposed to the elements, causing oxidisation which results in the ‘black’ appearance. Whiteheads are closed comedones.

Papules are small, raised red bumps which can be sensitive to touch. They’re often a sign of inflammation in pores or hair follicles.

Often (but not always) papules develop into pustules, which are filled with pus. These are what people typically think of when they imagine a pimple or spot. They’re red bumps, with yellow or white centres, often linked to overgrowth of bacteria or fungus on the skin, like Staphylococcus aureus, Streptococcus pyrogenes or Cutbacterium acnes. The bacteria trigger an inflammatory immune response as the body attempts to fight infection, creating pus (which is made up of white blood cells) within clogged pores.

Nodules and cysts are larger and more inflammatory. They usually extend deep into the skin. Nodules are solid to the touch, while white cysts are filled with fluid. If these are picked or not given proper care, they can lead to long-term scarring.

Acne can occur anywhere on the body, but is most common in areas with higher sebum production, or a higher concentration of hair follicles. This includes the face, neck, chest, upper back and shoulders.

People who remove their body hair may find they’re more susceptible to acne in those areas, as hair removal can irritate the hair follicle, or introduce bacteria to open pores.

You can (partly) blame your parents

Your genetics play a significant role in susceptibility and severity of acne. If you have a family history, you’re up to 80% more likely to have acne, due to genes which code for the local and big picture causes. The good news? Acne is not 100% caused by genetics. Your lifestyle and environment can change your gene expression.

The hormonal factors

Hormones, specifically androgens (male hormones) play a significant role. Both men and women produce androgens, which increase the size and activity of sebaceous glands, leading to excess oil production.

Higher levels of androgens result in increased conversion of androgens to dihydrotestosterone, a more potent hormone which promotes the production of fats and the growth and differentiation of cells which produce sebum.

These hormones also cause irregular multiplication of skin cells, leading to build up of a protein called keratin in sebaceous ducts, which connects sebaceous glands to the hair follicle.

Over time, this accumulation of sebum and cells in the sebaceous duct can cause micro-comedones to form, which can evolve into larger, visible skin lesions.

Androgens increase for both men and women during puberty. For women, androgens also go up during their 20s, during menopause, if they’re diagnosed with a condition called PCOS, and each month during the luteal phase – the week leading up to menstruation.

Female hormones, estrogen and progesterone, are also linked to acne. Progesterone regulates the menstrual cycle, and can increase sebum production, especially in the luteal phase.
If you notice your skin glowing around the time of ovulation, you can thank oestrogen, which usually decreases sebum, counteracting the effects of progesterone. However, a sharp increase or decrease of this anti-acne hormone can also trigger a breakout.

The delicate balance of oestrogen and progesterone, paired with their complex interactions with androgens and other hormones, means that a wide range of hormones needs to be tested to identify the unique hormonal factors which influence each person’s acne.

Stress

During the stress response corticotropin releasing hormone is produced. One of the effects of this hormone is increased sebum production, leading to clogged pores and increased inflammation.

Psychological and emotional stress often leads to fluctuations in male and female hormones, exacerbating acne.

Because acne is an inherently stressful condition, this often creates a feedback loop which can be difficult to break free from.

Bacteria

All of us have bacteria on our skin – good and bad. C. acnes, one of the strains of bad bacteria, thrives on sebum and dead skin cells. If this bacteria has lots of food, it colonises the skin, creating imbalances in the skin microbiome, exacerbating inflammation and acne.

The secretions of C. acnes activate immune and inflammatory responses and their enzymes degrade skin cells, tissues and structure.

When harmful skin bacteria congregate, they can form a biofilm which protects them from antibiotics, leading to further inflammation.

Environmental factors

In Hong Kong, we’re exposed to many factors which can trigger or worsen acne.

Airborne pollutants like traffic exhaust, or dust particles clog pores directly. Chemicals in our air, like nitrogen dioxide are also known to increase sebum production. Alongside other toxins in our environment, this increases oxidative stress, which contributes to the development of acne.

Humidity increases the production of sebum and sweat mixes with bacteria, make up and sebum on the skin causing congestion.

UV-related acne (like solar comedones or cysts) are non-inflammatory, and present quite differently from other types of acne.

What you eat shows on your skin

High glycaemic index foods like refined carbohydrates (white rice, white bread), dairy products, foods high in simple sugars (like chocolate, sweets or cake), and saturated fats (burgers, deep fried foods) have been linked to an increase in severity of acne.

Insulin and insulin-like growth factor-1 (IGF-1) are hormones that are produced when you eat, particularly if you’ve eaten high quantities of simple sugars and carbohydrates. These hormones activate androgen receptors, signalling for the growth of sebaceous gland cells and increasing sebum production.

Studies have shown that dairy also activates this pathway, increasing IGF-1 by 10 to 15%.

For many people, food allergies and intolerances go undiagnosed for years. Symptoms can be sneaky, manifesting as headaches, fatigue, joint pain – or acne. Without diagnosis, these people go on eating the foods causing havoc in their bodies, exacerbating symptoms.

Medication and skincare

Certain medications like contraceptives, or corticosteroids can trigger acne. Traditional medications for acne are also associated with skin problems like redness, dryness, peeling, irritation and eczema, which weaken the skin bacteria, allowing bacteria to enter the body more easily and worsen acne long-term.

Over-washing your skin can also damage your skin barrier, and you should limit face washing to once in the morning and once in the evening. Some people may be better suited to simply washing with water in the morning, rather than stripping their skin with products – but needs are very individual. Trust what your skin tells you – if it says it’s dry don’t subject it to more washing.

I recommend patch-testing skincare and makeup to see how your skin reacts before adding a new product to your routine.

Testing

Deciphering which factors are contributing to your skin problems can feel like an impossible puzzle. That’s where testing comes in. As a naturopath, I can diagnose acne during a clinical examination, and identify which further tests will provide valuable insights into the causes of your unique acne presentation.

Blood tests to identify hormonal imbalances can identify conditions associated with acne like PCOS, diabetes, or high cortisol – but this doesn’t provide the full picture. The DUTCH urine test also assesses female and male hormone metabolites, stress hormones, melatonin, inflammation markers and B vitamins, for the complete context.

Dermatoscope and woods lamp is an imaging system which evaluates your skin, checking whether bacterial or fungal infections are present, as well as ruling out other skin conditions that mimic acne, like fungal acne, rosacea or types of dermatitis.

GI testing identifies the impact the gut may be having on the skin via the gut-skin axis. While bacteria in the gut is distinct from the species that live on the surface, overgrowth of bad bacteria on the skin is linked to overgrowth in the digestive tract. If you have digestive symptoms, a GI-Map can pinpoint which strains of bacteria are causing problems.

Allergy and food sensitivity testing pinpoints environmental and food triggers which may be contributing to inflammation and breakouts. Environment and food induced acne has been found to be resistant to conventional treatment. The only effective treatment is the identification and removal of the trigger from your diet.

In summary

Acne is a complex, multifaceted condition that requires a comprehensive understanding of its symptoms, causes and management strategies. By recognising the various factors that contribute to acne, you can take proactive steps towards achieving clearer skin long-term.

I can diagnose you with acne and rule out other skin conditions, assessing your complete set of symptoms and recommending the right tests to identify the factors contributing to your skin problems.

The triggers for your acne don’t have to remain a mystery. You can find the answers and reclaim control of your skin. 

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