Inflammation, Insulin, & Your Gut: What Really Causes Acne Post

If you grew up in the ’90s or 2000s, you probably got your acne advice from cheesy skincare ads (scrub your pizza-face clean with magic soap, and suddenly you're prom royalty).

But those ads lied.

Acne isn't about dirty skin or your age. It's your body signaling deeper issues.

Here's what's really behind your adult acne and what to do about it.

What actually causes acne?

Acne happens when pores get clogged by excess oil (sebum), dead skin cells, and bacteria.

But the real issue starts deeper.

Acne isn’t just about bacteria. It's inflammation.

Studies show internal inflammation happens long before pimples appear¹ .

People with acne often have high inflammation markers like C-reactive protein (CRP)² (a sign your immune system is involved³ .

Gut microbiome and gut-skin axis.

Something else that causes inflammation? Dysbiosis.

When your gut bacteria gets out of balance (known as dysbiosis), it can rile up your immune system, fueling acne even more⁴ .

Insulin and sugar spikes.

Sugar-heavy diets spike insulin, activating pathways like mTORC1⁵ , which increases oil production and skin cell growth, perfect conditions for acne⁶ .

Dairy, especially skim milk, can also trigger acne by raising IGF-1 (though your response depends partly on genetics⁷ .

Hormonal imbalances (women)

Adult female acne often ties back to androgens: higher "male" hormones like testosterone, or extra sensitivity to them.

These hormones supercharge your oil glands, flooding skin with sebum⁸ .

That's why hormonal shifts, like before your period, pregnancy, or perimenopause, can worsen acne.

Hormonal imbalances (men)

Men naturally have high testosterone, which drives acne.

Those extra-sensitive or with very high levels have worse breakouts. Steroid users are nearly 4x more likely to develop severe acne needing medical help⁹ .

Stress and sleep:

Stress releases cortisol, increasing inflammation and oil production¹⁰. One study found students' acne worsened proportionally to their stress levels¹¹.

Poor sleep also makes acne worse¹², and brings on sleep-deprived sugar cravings that spike insulin¹³.

Genetics:

You're three times more likely to develop acne if it runs in your family¹⁴ .

Researchers have linked TNF and IL‑1 gene variants to inflammation and oil gland overactivity (genome-wide association studies)¹⁵ .

Environmental pollution:

Air pollution triggers oxidative stress, draining antioxidants and ramping up inflammation and skin cell growth.

One study found severe air pollution raised acne odds by over 8 times¹⁶ .

Hot, humid weather also fuels acne. Every 1°C rise in ambient temperature can boost skin oil production by about 10%¹⁷ .

What can you do about it?

🥗 Diet & gut health

• Reduce sugar and white carbs (low-glycemic diet) to lower insulin spikes.

• Test reducing dairy.

• Eat more fiber and prebiotic foods for gut health.

• Try probiotics (Lactobacillus, Bifidobacterium).

• Filter your water, it’s filled with skin-irritating toxins¹⁸.

• Consider a gut microbiome test.

😴 Sleep & stress

• Aim for 7–9 hours of quality sleep.

• High stress = high cortisol = more breakouts.

⚤ Hormone balancing

• Consider natural hormone regulators like inositol.

  • Myo-inositol is best for insulin sensitivity, while D-chiro-inositol may support androgen regulation in women with PCOS¹⁹ .

• Men: avoid anabolic steroids or hormone supplements.

• If hormonal imbalance is suspected, get tested (like with Superpower²⁰ ).

🧪 Evidence-backed supplements

• Vitamin D (1000–2000 IU/day): low levels are common in acne sufferers²¹ .

• Zinc (15–30mg/day): reduces inflammation effectively²² .

• Omega-3 fatty acids (2–3g EPA/DHA daily): shown to have a 79% acne improvement in studies²³ .

• Vitamin A*: regulates skin turnover and reduces sebum²⁴ . *Note: medical supervision needed at high dosages.

• Evening primrose oil: helps balance hormones and strengthen skin.

• Chromium/berberine (for PCOS sufferers): regulate insulin, reduce androgenic acne (promising but preliminary)²⁵ .

✨ Dermatologist-approved procedures

• LED blue-light therapy kills acne bacteria²⁶ .

• Chemical peels can unclog pores and reduce scars²⁷ .

Skincare routine for acne-prone skin

Acne-prone skin isn't dirty; it's inflamed. Your goal? Calm it down, not scrub it into submission.

Key rules:

• Less is more: Gentle, consistent routines beat aggressive “acne-fighting” regimens.

• Barrier over burn: Most acne-prone skin has a weakened barrier. Harsh products only worsen inflammation and delay healing.

• Treatment + tolerance: Effective actives (like retinoids or Benzoyl Peroxide) must be paired with barrier-supporting moisturizers.

Step 1: Cleanse (1–2x/day)

Use a gentle, non-stripping cleanser (glycerin, ceramides, panthenol).

Skip foaming scrubs, SLS, brushes and anything labeled “deep cleansing.” This will avoid stripping the skin.

Step 2: Treat (apply targeted ingredients at night)

Start slow with just one or two targeted ingredients:

• Retinoids: unclogs + calms

• Benzoyl Peroxide: kills acne bacteria

• Azelaic Acid: soothes redness

• Niacinamide: balances oil + barrier

• Salicylic Acid: de-gunks pores

Step 3: Moisturize (AM + PM)

Use pore-safe moisturizers with ceramides, niacinamide, or squalane. Even oily skin needs hydration.

Step 4: Sun protection (daily)

Sun exposure worsens acne scars, redness, and post-inflammatory hyperpigmentation.

Go for oil-free mineral sunscreens (zinc or titanium).

Acne add-ons?

Pimple patches might feel like little stickers teenagers slap on before TikToks, but the science is legit. They’re tiny wound covers stopping you from picking (be honest, you do it), letting your skin actually heal²⁸ .

Some even have hydrocolloid, which pulls out the gunk overnight.

Masks? The old-school clay ones with bentonite and kaolin, still hold up. They mop up excess oil, reduce shine, and give your skin a fighting chance.

And gentle chemical exfoliants (salicylic or mandelic acid) keep pores clear, just go easy.

Forget quick fixes and miracle cleansers.

The real key to lasting clear skin? Combining proven treatments tailored just for you.

Reviewed by Julija Rabcuka, BA (Oxon), MSc, PhD (ABD), University of Oxford.

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