Acne on the body: back, chest, torso - causes and solutions

Causes and aggravating factors of body acne¹

Although the mechanisms of body acne are similar to facial acne, some features are distinct. The main factors in the development of acne include follicular hyperkeratinisation (abnormal thickening of the skin, preventing sebum from draining properly), colonization by the bacterium Cutibacterium acnes, and inflammation. Sebum production is also less significant in the trunk area.

Hormones,particularly androgens during puberty, significantly influence the development of acne by stimulating follicular keratinocyte proliferation, bacterial growth, and sebum production. Hormonal disorders such as polycystic ovary syndrome (PCOS) can also promote the appearance of acne on the body.

The cutaneous microbiota also plays a role in acne. Bacterial populations differ between body skin (predominance of enterococci) and facial skin (predominance of Cutibacterium acnes and staphylococci).  Reduced microbial diversity also appears to influence the severity of acne by favouring the proliferation of certain strains of Cutibacterium acnes involved in cutaneous inflammation.

The skin on the body has specific characteristics that make it particularly vulnerable to certain aggravating factors:

• Greater thickness
• A distinct pH that can affect skin balance
• A unique distribution of sebaceous glands
• Increased sensitivity to mechanical factors such as perspiration, friction, pressure, and occlusion

Genetic predisposition also plays a role, particularly in scar formation. 

Symptoms of body acne¹

Body acne manifests as a variety of skin lesions ranging from comedones to more severe lesions such as papules, pustules, and nodules. These lesions appear mainly on the torso and back and are generally concentrated along the body's midline.

The distribution of lesions varies according to anatomical area, with a predominance on:

• Upper back (52% of cases)
• Upper chest (30% of cases)
• Lower back (22% of cases)
• Shoulders and arms (16% of cases)
• Neck (8% of cases)

Studies have explored the differences between men and women regarding lesion location. In men, acne mainly affects the back (19.4%), followed by the chest (18.1%), while in women, it affects the back (13.9%), neck (12.7%), and chest (11.1%).

In severe forms, such as acne conglobate, nodules, abscesses, and deep cysts are seen on the chest, shoulders, back, and arms. Acne fulminans, the most severe form, is characterized by the sudden appearance of painful inflammatory plaques with ulcers and haemorrhagic scabs on the chest and back, usually sparing the neck. These severe forms often leave scars, usually thick and raised (hypertrophic).

What treatments are available for body acne?¹ ²

The general principles of acne treatment for the body are similar to those applied to the face, but managing body acne requires a few adjustments. The surface area to treat, the differences in skin texture, and the high risk of hypertrophic scarring make early and appropriate intervention essential. Although there are no specific guidelines, dermatologists generally recommend using treatment approaches similar to those for facial acne while adapting the method of application and duration.

Local treatments 

Local treatments such as benzoyl peroxide and retinoids represent the first line of treatment for mild to moderate body acne. They reduce inflammation, prevent comedone formation, and limit new lesion formation, gradually improving the appearance of the skin on the back, chest, and shoulders. Given the extent of the areas to treat, using gels and lotions is often necessary. 
Continuing topical treatments even after visible improvement ensures long-term remission and prevents relapses.

Note that benzoyl peroxide can discolour clothing and bed linen.

Oral treatments

• Antibiotics (cyclines)

Oral antibiotics such as doxycycline or lymecycline can be combined with local treatments for moderate to severe body acne. Used over a limited period to prevent resistance, they reduce inflammation.

• Oral isotretinoin

Isotretinoin is the reference treatment for severe, very severe, and resistant acne,or acne with a high risk of scarring, as a second-line treatment after conventional, well-administered therapy fails.It requires close medical supervision, given its potential side effects and the need for contraception in women of childbearing age.

• Oral contraceptives and hormone treatments

Some contraceptive pills can help improve acne in women. 
In situations associated with hyperandrogenism, the use of specific hormonal treatments is decided after consultation between the patient, her dermatologist, and her gynaecologist.

Preventing acne on the back, chest, and shoulders³ ⁴

Preventing acne on the body requires a global approach, combining appropriate hygiene, specific care, and a balanced lifestyle. Adopting simple daily habits helps reduce the appearance of new breakouts and prevents existing ones from worsening.

 Appropriate body care and post-exercise shower

• Opt for loose-fitting, breathable clothing
  Choose fabrics such as cotton or anti-perspiration technical materials to wick away moisture and prevent sebum and bacteria build-up. Tight-fitting or synthetic clothing can irritate the skin and cause pores to clog.
   
• Shower quickly after any sporting activity
  After a workout or sports session, perspiration accumulates and mixes with excess sebum and impurities. A quick shower using gentle cleansing products without rubbing reduces sebum, prevents bacterial proliferation, and limits the appearance of new lesions on the back, chest, and shoulders.

Non-comedogenic products and gentle gestures

• Use mild, pH-balanced cleansers
  Opt for non-aggressive dermatological gels that are free from alcohol and irritating antiseptics. Non-comedogenic formulas, specially designed for acne-prone skin, cleanse without damaging the cutaneous barrier.
   
• Avoid aggressive scrubs and irritating practices
  Hard brushes and abrasive scrubs can weaken the epidermis and exacerbate inflammation. Gentle cleansing without scrubbing preserves the skin's balance and limits inflammatory reactions.

Sun protection

The sun can thicken the skin, aggravate acne (rebound effect when exposure is stopped), and promote post-inflammatory hyperpigmentation. Appropriate sun protection helps prevent these undesirable effects. Look for shade in the summer and use a high-protection sun cream adapted to acne (oil-free, non-comedogenic formulas).

Health and nutrition 

• Do not manipulate the lesions
  Scratching, squeezing, or piercing lesions aggravates inflammation, promotes scarring, and prolongs acne duration. Adopt a "hands-free" approach to reduce the risk of contamination and superinfection.
   
• Managing stress and avoiding tobacco
  Stress and smoking harm the skin. Stress can increase sebum production, while smoking reduces skin oxygenation and promotes inflammation. Learning to manage stress, practicing regular physical activity, or consulting a mental health professional can help reduce the influence of these factors on acne.
   
• Adapting your diet
  Although the exact role of diet remains debated, limiting foods with high  glycaemic index, dairy products, and snacking could contribute to a better skin balance. A healthy lifestyle, with a well-balanced diet rich in fruit and vegetables, appears to be generally favourable.

Managing the scars and psychological impact of body acne¹ ⁵

The psychological and emotional impact of body acne can profoundly affect the quality of life. In people suffering simultaneously from facial and body acne, distress is even more substantial, resulting in a significant drop in self-esteem, anxiety, and even depressive symptoms. These effects, sometimes amplified during the summer months when the body is more exposed, do not always disappear when skin symptoms improve. A global approach integrating scar treatment and psychological support is necessary to restore a satisfactory quality of life.

Dermatological management of acne scars on the body

Reducing body acne scars often involves specialised treatments, such as chemical peels, lasers, or dermabrasion. By improving the appearance of the skin, these approaches can help restore self-confidence. 

Psychological support, impact assessment, and global approach

Beyond the physical dimension, emotional well-being and psychological support must be considered. A multidisciplinary approach, involving dermatologists, psychologists or psychiatrists, and other healthcare professionals, can help reduce the discomfort associated with acne.