Acne gets worse when something increases oil production, triggers inflammation, or clogs pores, and often it’s a combination of all three. The most common culprits are hormonal shifts, high-sugar diets, stress, certain medications, and everyday habits you might not suspect. Understanding which factors are driving your breakouts is the first step toward getting them under control.
High-Sugar Foods and Dairy
Foods that spike your blood sugar quickly, like white bread, sugary drinks, chips, and candy, trigger a chain reaction in your body that feeds acne. When blood sugar rises fast, your body floods the bloodstream with insulin. High insulin levels do two things that matter for your skin: they ramp up oil production by stimulating androgen hormones, and they increase levels of a growth factor called IGF-1 that pushes your oil glands into overdrive. The result is more sebum, more clogged pores, and more breakouts.
Dairy is a separate but related trigger. Milk contains both casein and whey protein, which raise insulin and IGF-1 levels independently of blood sugar. Dairy also naturally contains sex hormones, including androgens, that can directly stimulate the oil glands. This doesn’t mean you need to eliminate all dairy, but if your breakouts cluster around your chin and jawline, cutting back on milk, cheese, or whey protein supplements for a few weeks can be a revealing experiment.
Hormones and Oil Production
Your oil glands are essentially hormone-sensitive targets. The main driver is a potent form of testosterone called DHT, which binds to receptors in the oil glands with ten times the strength of regular testosterone. What makes this especially relevant is that your skin doesn’t need to wait for hormones circulating in your blood. Sebaceous glands contain the enzymes to manufacture their own testosterone and DHT from weaker precursor hormones, creating a localized hormone surge right where it can do the most damage.
When DHT activates these receptors, it increases the gland’s size and lipid output, creating the thick, sticky sebum that plugs follicles. It also amplifies the inflammatory response from immune cells like macrophages and neutrophils. So androgens don’t just make your skin oilier; they also make existing breakouts angrier and more inflamed. This is why acne flares are so common during puberty, before periods, during polycystic ovary syndrome, and at any other point when androgen activity increases.
Stress and Sleep Loss
Stress doesn’t cause acne on its own, but it reliably makes existing acne worse. When you’re stressed, your brain releases corticotropin-releasing hormone (CRH), a stress signal that does more than just make you feel anxious. CRH receptors exist directly on your oil glands, and when activated, they stimulate both oil production and localized inflammation. Research on acne-affected skin has found elevated CRH expression in the oil glands of breakout zones compared to clear skin, suggesting stress creates a self-reinforcing cycle in areas already prone to acne.
Poor sleep compounds the problem through a similar pathway. Sleep deprivation raises cortisol levels and increases the production of inflammatory molecules, specifically TNF and IL-6, two signals that promote swelling, redness, and pus formation. Your body essentially enters a low-grade inflammatory state when you’re not sleeping enough, and your skin reflects that. If you notice your breakouts get worse during exam weeks, tight work deadlines, or any period when you’re sleeping less than six hours, this connection is likely playing a role.
Friction, Pressure, and Heat
Physical irritation causes a specific type of breakout called acne mechanica, a bumpy, inflamed rash triggered by pressure, friction, occlusion, or heat acting on the skin. Common sources include helmet straps, tight sports bras, backpack straps, face masks, and headbands. If you consistently break out along the lines where equipment or clothing presses against your skin, mechanical irritation is the likely cause. The fix is straightforward: use moisture-wicking fabric underneath, clean equipment regularly, and remove tight gear as soon as possible after activity.
Skincare Products That Clog Pores
Some of the products you’re using to care for your skin may be feeding your breakouts. In facial cleansers, certain harsh surfactants along with lauric acid and stearic acid are among the most common pore-clogging ingredients that also irritate and disrupt the skin barrier. In moisturizers, glyceryl stearate is a frequently identified comedogenic ingredient. Thick foundations, oil-based primers, and occlusive sunscreens can also trap sebum inside follicles.
Look for “non-comedogenic” on labels, but don’t rely on it entirely since the term isn’t regulated. When testing a new product, introduce it alone for two to three weeks so you can identify the source if new breakouts appear.
Over-Washing Your Face
It seems logical that washing more would mean cleaner pores and fewer breakouts, but excessive cleansing is a recognized risk factor for both acne and skin sensitivity. Harsh cleansers, especially those with strong surfactants or alkaline formulas, strip away the skin’s natural protective layer and shift its pH. This damages proteins involved in barrier repair and disrupts the balance of bacteria living on your skin’s surface. A compromised barrier is more vulnerable to inflammation and bacterial overgrowth, both of which worsen acne. Washing twice a day with a gentle, pH-balanced cleanser is enough for most people.
Certain Medications
A number of prescription drugs can trigger or worsen acne-like breakouts. Corticosteroids are among the most common offenders, whether taken orally, injected, or applied as a cream. Steroid-induced breakouts tend to appear on the chest and back more than the face and look uniform in size, which helps distinguish them from regular acne. Other medications linked to acneiform eruptions include lithium, vitamin B12 supplements at high doses, certain anti-seizure drugs, thyroid hormones, and some immunosuppressants. If you started a new medication and noticed a flare within weeks, mention the timing to your prescriber.
Picking and Squeezing
Compulsive picking at acne lesions, sometimes called acne excoriée, pushes bacteria and inflammatory debris deeper into the skin and spreads it to surrounding tissue. What starts as a small whitehead can become a swollen, painful nodule after manipulation. Beyond making individual spots worse, repeated picking causes significant scarring and long-lasting dark marks, particularly on deeper skin tones. The condition is most common in adolescent and young adult women and can become a compulsive habit that’s difficult to break without support.
Air Pollution
Particulate matter, nitrogen oxides, and chemicals called polycyclic aromatic hydrocarbons (PAHs) from vehicle exhaust and industrial emissions have been linked to acne flares. These pollutants settle on the skin and promote oxidative stress and inflammation, impairing barrier function and altering the balance of skin bacteria. Research on people exposed to high PAH levels has found changes in skin microbiota and metabolic profiles consistent with increased acne severity. If you live in a high-pollution area or commute in heavy traffic, cleansing your face in the evening to remove particulate buildup becomes especially important.