Acne: what causes breakouts and which ingredients help
What causes acne, the types of pimples, the best ingredients for acne and a simple routine to clear breakouts, plus when hormonal acne needs a doctor.
By the Green Point editorial teamUpdated 6 min readKey takeaways
- Acne starts when pores clog with oil and dead skin cells; bacteria and inflammation then turn some of them into red, swollen pimples.
- Hormones, genetics, stress, some medicines and heavy, oily products all make breakouts more likely.
- Salicylic acid, benzoyl peroxide, adapalene, azelaic acid and niacinamide are the most useful ingredients for mild to moderate acne.
- Treatments take 6 to 12 weeks to show results, so pick one plan and stick with it.
- Deep, painful or scarring acne needs a doctor, not more products.
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Acne happens when hair follicles (pores) get blocked with excess oil and dead skin cells. Bacteria that live on the skin can then multiply in the blocked pore and trigger inflammation, which turns it into a red pimple. Hormones, genetics and pore-clogging products make this more likely. Ingredients such as salicylic acid, benzoyl peroxide and adapalene help most people with mild acne.
What causes acne?
Four things happen together in an acne breakout: the skin makes too much sebum (oil), dead cells don't shed properly and clog the pore, the bacterium Cutibacterium acnes (formerly Propionibacterium acnes) grows in the oily, blocked pore, and the body reacts with inflammation. Several factors push this process along:
- Hormones. Androgens stimulate oil glands, which is why acne often starts at puberty and can flare around periods, during pregnancy, in perimenopause and after starting or stopping birth control pills.
- Genetics. You are more likely to have acne, and deep acne in particular, if close relatives did.
- Stress. Stress makes the body produce more androgens, which can worsen breakouts in people prone to acne.
- Products. Greasy skin and hair products can clog pores. Oil from hair can cause breakouts along the forehead.
- Medicines and medical conditions. Some medicines list acne as a side effect, and sometimes acne is a sign of an underlying condition.
Dirt does not cause acne, and washing more often won't fix it. Scrubbing irritates skin and can make breakouts look worse.
Types of acne: from blackheads to cysts
| Type | What it looks like | Where to start |
|---|---|---|
| Blackheads | Open clogged pores with a dark top (oxidized oil, not dirt) | Salicylic acid, adapalene |
| Whiteheads | Closed clogged pores, small skin-colored bumps | Salicylic acid, adapalene |
| Papules | Small, firm, red or darker bumps without a head | Benzoyl peroxide or salicylic acid wash |
| Pustules | Raised bumps filled with pus | Benzoyl peroxide or salicylic acid |
| Nodules and cysts | Large, deep, often painful lumps under the skin | See a doctor: they often scar |
Most people have a mix. If blackheads are your main issue, read our guide on how to get rid of blackheads.
Hormonal acne in adults
Acne is not just a teenage problem. Many women keep getting breakouts into their 20s, 30s and 40s, often flaring around their period. Breakouts along the jawline and lower face are a common pattern, and dermatologists note that women with this pattern tend to respond well to hormonal therapy. The same ingredients below can help, but if breakouts are persistent or come with irregular periods or extra hair growth, talk to a doctor. Prescription options such as some birth control pills or spironolactone can target the hormonal side; spironolactone must not be taken during pregnancy.
Best ingredients for acne
These are the over-the-counter ingredients dermatologists use most. Pick one to start, and add a second only once your skin tolerates the first.
- Salicylic acid (BHA) dissolves in oil, so it works inside the pore to clear blackheads and whiteheads. It suits oily skin. See how salicylic acid helps your skin.
- Benzoyl peroxide reduces acne bacteria and helps with red, inflamed pimples. Start with a low strength such as 2.5%, often as a wash. It can bleach towels and pillowcases.
- Adapalene is a retinoid that unclogs pores and prevents new ones. In the US, adapalene 0.1% gel is sold without a prescription; in many other countries you need one.
- Azelaic acid calms inflammation and also helps fade the dark marks pimples leave behind. Many people with sensitive skin tolerate it, though it can tingle or sting at first. See our azelaic acid guide.
- Niacinamide may help reduce oiliness and redness and supports the skin barrier, which makes it a good partner for stronger actives.
A simple acne skincare routine
- Morning: wash gently with a mild cleanser, apply a light non-comedogenic moisturizer, then a broad-spectrum SPF 30 or higher.
- Evening: cleanse (remove makeup first), apply your treatment, such as adapalene or a salicylic acid product, then moisturizer.
- Start slowly: use a new active every other night for the first two weeks if your skin is dry or sensitive.
- Wait: give the plan 6 to 12 weeks. Pimples can look worse at first with retinoids.
Use products labeled "non-comedogenic", "oil-free" or "won't clog pores", keep hair products off your face and don't pick or squeeze spots, which raises the risk of scars and dark marks. If your skin is also shiny, our guide to oily skin has more tips.
When to see a doctor about acne
Doctors can prescribe stronger creams, antibiotics, hormonal treatments or isotretinoin for severe acne. Starting early means fewer permanent scars.
Frequently asked questions
How can I get rid of acne fast?
There is no overnight fix for acne. A pimple usually settles on its own within days, and a small amount of benzoyl peroxide or a hydrocolloid patch may help it heal without picking. For clearer skin overall, you need a consistent treatment for 6 to 12 weeks. For a painful cyst before an important event, a dermatologist can sometimes inject it.
Does food cause acne?
Diet is not the main cause, but some studies suggest that high-glycemic foods (white bread, sugary drinks) and, in some people, milk may be linked to breakouts. The evidence is still limited. If you notice a pattern, try cutting back for a few weeks and see whether it makes a difference.
Can I use salicylic acid and benzoyl peroxide together?
Yes, many people do, but both can dry the skin. A common approach is a benzoyl peroxide wash in the morning and a salicylic acid product in the evening, or using them on alternate days. If your skin becomes red, tight or flaky, cut back to one and moisturize well.
Why is my acne getting worse after starting a new product?
Retinoids such as adapalene can cause a short flare in the first weeks as clogged pores come to the surface. This usually settles within a few weeks. Breakouts in new places, burning, itching or a rash are more likely irritation or a reaction to the product, so stop it and check with a pharmacist or doctor.
Sources
- AcneNHS
- How to treat different types of acneAmerican Academy of Dermatology
- Adult acneAmerican Academy of Dermatology
- Stubborn acne? Hormonal therapy may helpAmerican Academy of Dermatology
- 6 skin care habits that can clear acneAmerican Academy of Dermatology
This guide is for general information and is not medical advice. If you have a skin, allergy or health concern, talk to a doctor, dermatologist or dietitian. Green Point scores and Skin Scan results are informational and are not a diagnosis.
