Acne and Diet: Foods to Favour and Avoid

Acne is a chronic skin condition affecting around 80% of teenagers and many adults. While its causes are varied—particularly hormonal and genetic—the role of diet is attracting growing interest.

The Mechanisms of Acne¹ ²

Acne develops when pilosebaceous follicles become blocked. This may happen due to several factors:

• Excess sebum production triggered by androgens (male sex hormones).
• A build-up of dead skin cells clogging the pores.
• The overgrowth of bacteria such as Cutibacterium acnes.
• Local inflammation, worsened by immune responses.

Hormones play a central role in the development of acne, but they can also be influenced by external elements, particularly diet.

The Impact of Diet on Acne

For decades, researchers have been exploring how diet affects skin health. Two key factors stand out: high-glycaemic diets and dairy consumption. Studies in non-Western populations have shown that traditional diets—low in dairy and refined sugars—are associated with an almost complete absence of acne.

High-Glycaemic Foods¹ ³ ⁴

The glycaemic index measures how quickly food increases blood sugar levels. Foods with a high glycaemic index (such as white bread, fizzy drinks, and sweets) cause spikes in blood sugar, prompting insulin and insulin-like growth factor 1 (IGF-1) release—two hormones linked to acne. These hormones encourage:

• Sebum production, feeding the bacteria responsible for breakouts.
• Cell proliferation, blocking pores.

Studies also indicate that low-glycaemic diets help reduce the severity of acne.

Dairy Products¹ ³ ⁴

Milk and dairy contain proteins like casein and whey, which raise  IGF-1 growth factor levels and can stimulate sebum production. They also naturally include bovine hormones that may influence the human body. However, not all research agrees on the link between dairy and acne. Some scientists suggest that this effect could be influenced by individual factors such as sex or ethnicity.

Saturated Fats and Processed Foods³ ⁴

Saturated fatty acids and ultra-processed foods are believed to worsen acne by increasing inflammation and altering sebum quality. Saturated fats in fatty meats, fried foods, and pastries can intensify lesions by boosting sebum production and local immune reactions. Ultra-processed foods, high in refined sugars, saturated fats, and additives (like crisps, fizzy drinks, and ready-made meals), spark blood sugar spikes, raising IGF-1 levels and fuelling inflammation.

Other Environmental Factors Influencing Acne²

Unsuitable Skincare and Lifestyle Habits

Using the wrong products for your skin type, especially comedogenic cosmetics, can worsen acne by blocking pores. Failing to remove makeup or cleanse properly after hot days or exercise can trigger more breakouts. On the flip side, over-washing can irritate the skin and heighten inflammation.

Meanwhile, repeated friction from headbands, helmets, or tight clothing encourages sebaceous gland activity and may cause acne in those areas.

Lastly, picking or squeezing spots aggravates inflammation, delays healing, and increases the risk of permanent scarring.

Psychological Factors and Stress

Stress boosts sebum production by releasing a molecule called substance P, which activates the sebaceous glands. This extra sebum can clog pores and lead to inflammatory breakouts. Stress also prompts reflex actions like touching or scratching lesions, further irritating them and prolonging flare-ups.

Medications and Metabolic Disorders

• Medications that can worsen acne: Some treatments, such as steroids, lithium, or anticonvulsants, promote acne by disrupting hormonal balance or raising sebum production.
• Hormonal and metabolic disorders: Conditions like polycystic ovary syndrome lead to higher androgen levels, causing overactive sebaceous glands.

Environmental Factors

• Climate conditions: Hot, humid environments boost sweating and sebaceous gland activity, creating an ideal setting for bacterial growth.
• Sun exposure: While the sun may initially dry out spots, too much exposure worsens inflammation and can lead to hyperpigmentation or delayed acne breakouts.
• Smoking: Tobacco reduces tissue oxygenation and impairs the skin’s ability to regenerate, making acne lesions worse.

Which Foods to Favour for Healthy Skin?³ ⁴ ⁵

Adopting a balanced diet can help improve your skin’s condition. While genetic and hormonal factors influence acne, some studies show that what you eat can affect how severe your breakouts are.

Focus on Low-Glycaemic Foods

Foods with a low glycaemic index release glucose slowly, preventing the sugar spikes that trigger insulin and IGF-1 release. Several studies indicate that a low-glycaemic diet may reduce acne.

Such foods include fresh vegetables (broccoli, spinach), legumes like lentils, fruit, and wholegrain oats.

Cut Back on Dairy

Research has found that cow’s milk—whole, semi-skimmed, or skimmed—can aggravate acne, as can products high in whey, often used in bodybuilding supplements. You might try reducing your milk intake to see if your breakouts improve. Alternatives include plant-based drinks like almond or oat milk.

Include Anti-Inflammatory Foods

Because inflammation worsens acne, certain foods can help control this process:

• Omega-3 fatty acids found in oily fish (salmon, mackerel, herring), certain oils (like rapeseed) and nuts may help minimise inflammation.
• Foods high in zinc, such as oysters, lentils, or pumpkin seeds, can help regulate sebaceous gland activity and support healing.
• Antioxidants in grapes, berries, and green tea may also help reduce inflammation.

Limit Refined Sugars and Processed Foods

Sugary and processed foods boost inflammation and promote sebum production. This includes sweets, fizzy drinks, white bread, industrial baked goods, and snacks. For example, replace sugary desserts with fresh fruit and choose unsalted nuts over crisps. Cooking at home with healthy ingredients is a good way to prevent your acne nutritionally.

Precautions and Personalising Your Diet

Keep in mind that diet affects everyone differently. Past medical history, genetic predisposition, and lifestyle habits all play roles. For tailored advice on eating and managing acne, consult a healthcare professional.

Overall Lifestyle Recommendations for Acne

Choosing Non-Comedogenic Products and Gentle Techniques² ⁶

• Use mild, pH-balanced cleansers specifically designed for acne-prone skin.
• Avoid products containing alcohol or harsh antiseptics.
• Choose non-comedogenic formulas that remove impurities and excess sebum without damaging the skin’s protective barrier.

Avoid aggressive scrubs and irritating habits:

• Skip hard brushes and abrasive exfoliants that weaken the skin.
• Avoid over-washing, which can irritate and inflame.
• Take a gentle approach to cleansing to preserve your skin’s balance and limit inflammation.

Healthy Habits⁵ ⁶

Touching, popping, or scratching spots increases inflammation, extends healing time, and raises the risk of scarring. Avoid touching acne lesions.

Stress can aggravate acne by boosting sebum production through specific neurotransmitters and encouraging picking behaviour. Consider relaxation methods like yoga or meditation for your daily routine.
Smoking heightens inflammation and harms skin quality. If you smoke, quitting benefits your overall health and your skin.

Suitable Sun Protection⁵ ⁶

While the sun may briefly improve acne, it can thicken the skin, block pores, and provoke a rebound effect when exposure ends. UV rays also raise the likelihood of post-inflammatory hyperpigmentation. Use a high-SPF sunscreen developed for acne-prone skin with non-oily, non-comedogenic formulas. Seek shade and wear protective clothing in the summer.

If You Experience Body Acne⁷ 

• Opt for loose, breathable clothing
  When dealing with body acne, use natural fabrics like cotton or moisture-wicking technical materials that reduce sweat build-up. Tight or synthetic clothes can irritate the skin and block pores, leading to acne breakouts.
   
• Shower promptly after exercise
  Sweat mingling with sebum and impurities can clog pores after workouts. A quick shower with suitable products helps wash away these residues, preventing new back, shoulders, or chest breakouts.