Can Caffeine Cause Acne? The Science Explained

Caffeine by itself has not been shown to directly cause acne, but it can nudge several biological systems in directions that make breakouts more likely. The hormone cortisol, insulin sensitivity, sleep quality, and the ingredients you mix with your caffeine all play interconnected roles. The picture gets more interesting when you learn that some compounds naturally found in coffee may actually work against acne, meaning the net effect depends heavily on how you get your caffeine and what comes along with it.

How Caffeine Raises Cortisol and Why That Matters for Skin

One of the most well-established effects of caffeine is its ability to stimulate cortisol release. In a controlled study, participants who had abstained from caffeine for five days showed a strong cortisol spike when given a caffeine challenge, and even habitual consumers who had adapted to a morning dose still showed elevated cortisol after an afternoon dose.¹ Another study found that caffeine amplified cortisol responses to mental stress and exercise, and that repeated doses throughout the day kept cortisol elevated regardless of the type of stressor.²

Why does cortisol matter for your skin? Cortisol is a stress hormone, and stress has long been linked to acne flares. Research on young women with acne found a significant correlation between cortisol levels and acne severity scores.³ Cortisol can boost sebum production and inflammation, both of which contribute to clogged pores and the red, swollen lesions that characterize acne. So the chain runs: caffeine raises cortisol, cortisol promotes conditions that favor breakouts. That said, your body adapts to habitual caffeine use over time, and the cortisol response to your morning cup is blunted compared to what happens when an infrequent user gulps down espresso. The effect is real, but it is strongest for people who consume caffeine irregularly or in large, spaced-out doses.

The Insulin Sensitivity Problem

Caffeine also affects how your body handles blood sugar. A systematic review pooling data from multiple controlled trials found that caffeine significantly decreased insulin sensitivity in healthy people.⁴ In one study, caffeine reduced glucose disposal by about a quarter compared to a placebo, and carbohydrate storage dropped by roughly a third.⁵

When insulin sensitivity drops, your body compensates by producing more insulin to deal with the same amount of sugar. Higher circulating insulin ramps up levels of insulin-like growth factor 1 (IGF-1), and IGF-1 is one of the key drivers of sebum production in skin cells. Lab research has shown that IGF-1 activates pathways in sebocytes (the cells that produce oil in your skin) that turn on fat-making genes, leading to more oil output.⁶ The broader picture has been described in the dermatology literature: nutrient-rich Western diets activate a signaling hub called mTORC1, which integrates signals from insulin, IGF-1, and certain amino acids to drive fat production in skin glands.⁷ Caffeine’s temporary hit to insulin sensitivity can feed into this cycle. Again, this is a contributing factor rather than the sole cause, and the magnitude of the effect depends on how much caffeine you consume, what you eat alongside it, and your individual metabolic profile.

What You Add to Your Coffee Probably Matters More

Here is where the evidence gets genuinely interesting. A study of medical students in Jakarta compared acne severity between black coffee drinkers and those who drank coffee mixtures (lattes, frappuccinos, sweetened coffee drinks). Students who stuck to plain black coffee had significantly lower acne severity scores than those who drank mixed coffee beverages. In fact, more black coffee consumption was correlated with lower acne severity, while more mixed-coffee consumption was correlated with worse acne.⁸ This is one study in a specific population, so it is not definitive, but it strongly suggests that the sugar and dairy in your coffee drink are doing more damage than the caffeine itself.

The dairy connection is backed by a meta-analysis of over 78,000 children, adolescents, and young adults, which found that consuming any dairy was associated with roughly 25 percent higher odds of acne. Skim and low-fat milk showed a slightly stronger association than whole milk.⁹ That finding has a counterintuitive wrinkle: skim milk appears slightly worse than whole milk for acne. The reasons are debated, but dairy proteins and their effect on IGF-1 are suspected more than milk fat content.

Sugar is the other big confounding factor. A randomized controlled trial found that switching acne patients to a low-glycemic-load diet reduced total acne lesions significantly more than a conventional diet, while also improving insulin sensitivity.¹⁰ This matters because many popular coffee drinks are essentially desserts. A vanilla latte or caramel frappuccino delivers a dose of dairy and a sugar load that hits the same metabolic pathways caffeine does, except more powerfully. When people blame coffee for their breakouts, the real culprits are often sitting in the cup alongside the coffee.

Coffee’s Protective Compounds

Black coffee contains chlorogenic acid, a polyphenol with biological effects that run directly counter to the acne-promoting pathways described above. Research in skin cells and animal models has found that chlorogenic acid reduces inflammation and inhibits fat production in sebocytes. In one study, chlorogenic acid effectively reduced swelling and redness in mice whose skin was exposed to acne-causing bacteria, and it dampened inflammatory signaling while also blocking the same fat-making pathway (the AKT/mTOR/SREBP pathway) that insulin and IGF-1 activate.¹¹ Separately, chlorogenic acid has been shown to modulate inflammatory signaling in human skin cells.¹²

This is part of why the Jakarta study’s finding makes biological sense: black coffee delivers chlorogenic acid without burying it under sugar and dairy. The polyphenol may partially offset some of caffeine’s acne-promoting hormonal effects. Green tea, which contains different polyphenols but overlapping mechanisms, is often discussed in the same context, and some researchers have suggested that the antioxidant and anti-inflammatory content of a caffeinated beverage can matter as much as the caffeine itself when it comes to skin outcomes. The takeaway is that caffeine is only one ingredient in a complex mix, and the other components of your drink can push the balance in either direction.

Caffeine, Sleep, and a Vicious Cycle

There is one indirect route by which caffeine can worsen acne that gets overlooked: sleep disruption. Caffeine consumed too late in the day delays sleep onset and fragments sleep architecture, and poor sleep has its own links to skin health. A comprehensive review on sleep disturbances and acne found that poor sleep (generally defined as fewer than five hours or poor quality) increases water loss through the skin, impairs the skin barrier’s ability to recover overnight, and weakens defenses against external irritants.¹³ A damaged skin barrier makes existing acne worse and makes it easier for new breakouts to develop.

Poor sleep also raises cortisol independently of caffeine. So if you’re drinking coffee in the afternoon or evening, you get a double hit: the cortisol from the caffeine itself, and the cortisol from the poor sleep that follows. For people who already have acne-prone skin, this combination is worth paying attention to. Cutting off caffeine by early afternoon is standard sleep hygiene advice, but it turns out to be decent skin hygiene advice as well.

Not All Caffeine Sources Are Equal

Black coffee, green tea, energy drinks, pre-workout supplements, and chocolate all contain caffeine, but they deliver wildly different packages of additional ingredients. Energy drinks are a particularly relevant example. Many contain high doses of B vitamins (especially B12, which has been linked to acne flares in some research), large amounts of added sugar, and other stimulants alongside caffeine. The sugar alone can drive the insulin and IGF-1 spikes discussed earlier, and some of these added ingredients have their own independent effects on skin. When someone who regularly drinks energy drinks notices worse acne, pinning the blame on caffeine alone misses the bigger picture.

Green tea, by contrast, is high in a polyphenol called epigallocatechin gallate (EGCG), which has anti-inflammatory and anti-sebum properties studied in the dermatology literature. A cup of green tea delivers caffeine alongside compounds that may work against breakouts, much the way black coffee delivers chlorogenic acid. The net effect of a caffeinated beverage on your skin is not just about how much caffeine it contains but about the full chemical profile of the drink.

Pre-workout supplements add another wrinkle. Some contain not only caffeine but also branched-chain amino acids (BCAAs), particularly leucine. Leucine is one of the amino acids that most strongly activates the mTORC1 pathway, which as we saw is a central driver of sebum production.⁷ If you’re noticing breakouts that seem to coincide with gym days, the combination of caffeine, leucine, and cortisol spikes from intense exercise could be working together.

Caffeine and the Gut

There is growing interest in how gut health influences skin, and caffeine may play a role there too. An animal study on obese rats fed a high-fat diet found that caffeine helped reduce gut permeability (so-called “leaky gut”) and lowered circulating levels of bacterial toxins. The combination of caffeine with naringenin, a plant compound, produced the most pronounced improvements in gut microbiota balance.¹⁴ This is rodent research and should be interpreted cautiously, but it hints that caffeine’s effects on the gut could, in some contexts, work in favor of skin health rather than against it. A healthier gut barrier means fewer inflammatory molecules leak into the bloodstream, which could reduce the systemic inflammation that contributes to acne.

The gut-skin connection is still an emerging area of research, and it would be premature to drink coffee specifically for gut-mediated skin benefits. But it complicates the narrative that caffeine is simply bad for acne. The overall relationship looks more like a tug-of-war between caffeine’s pro-acne effects (cortisol, insulin resistance) and its potential anti-acne effects (polyphenol delivery, possible gut benefits), with the outcome depending on the individual and the form of caffeine consumed.

Topical Caffeine Is a Different Story

Caffeine applied directly to the skin behaves quite differently from caffeine you swallow. When used in topical formulations, caffeine penetrates the skin barrier effectively and has been shown to boost local blood flow and inhibit an enzyme called 5-alpha-reductase, which converts testosterone into a more potent form that drives oil production in the skin.¹⁵ Blocking 5-alpha-reductase is actually a recognized mechanism for controlling sebum, and it is the same enzyme targeted by some prescription acne and hair-loss treatments.

Topical caffeine also delivers antioxidant effects directly where they are needed without the systemic cortisol or insulin effects of oral consumption. This is why caffeine appears in a growing number of skincare products marketed for oily skin and acne. The irony is not lost on dermatology researchers: the same molecule that might worsen acne when you drink large amounts of it in a sugary latte could help control acne when applied to your face. Whether topical caffeine alone is potent enough to make a real clinical difference for moderate-to-severe acne has not been established in large trials, but its mechanism of action makes biological sense as one ingredient in a multi-target treatment approach.

Practical Adjustments If You Suspect Caffeine Is Affecting Your Skin

If you think your caffeine habit is contributing to breakouts, a few changes are more likely to help than simply quitting caffeine entirely:

Switch to black coffee or plain tea. Eliminating the added sugar and dairy removes the two dietary factors with the strongest acne evidence. A splash of non-dairy milk is a reasonable middle ground if you can’t stomach it black.
Cut caffeine by early afternoon. Protecting your sleep removes one of the indirect pathways by which caffeine can worsen skin.
Watch your total intake. The cortisol effect is dose-dependent, and habitual moderate intake produces a smaller cortisol response than occasional large doses. Steady, moderate consumption is gentler on your hormonal profile than binge-and-abstain patterns.
Look beyond the caffeine. If you drink energy drinks or heavily sweetened coffee beverages, the sugar and added ingredients are likely contributing more to your acne than the caffeine. Switching to a less processed caffeine source is a more targeted intervention than going caffeine-free.
Give changes time. Acne responds slowly to dietary shifts. If you change your caffeine habits, give it at least six to eight weeks before evaluating whether it made a difference, since that is roughly the time it takes for existing comedones to cycle through.

Why Definitive Answers Are Hard to Come By

One reason the caffeine-acne question remains murky is that acne research in general is plagued by confounding variables. People who drink a lot of coffee also tend to sleep less, eat more convenience food, and experience more work-related stress, all of which independently affect skin. Isolating caffeine’s contribution from these intertwined lifestyle factors requires the kind of tightly controlled, long-term interventional trials that are expensive and difficult to run for a condition that, while distressing, is not life-threatening. Most of the evidence we have comes from observational studies, mechanistic lab work, or short-term metabolic trials that measure surrogate markers like cortisol or insulin rather than actual pimple counts over time.

The Jakarta study comparing black coffee and mixed coffee beverages is one of the few that looked directly at coffee consumption and acne severity, and even it was cross-sectional, meaning it captured a snapshot rather than tracking people over time.⁸ People who choose black coffee over flavored drinks may differ in other ways, from diet to stress management habits, that also affect their skin. The biological mechanisms linking caffeine to acne are plausible and well-supported individually, but the full chain from your morning cup to a breakout on your chin has not been proven in the way that, say, the link between isotretinoin and acne clearance has been proven. The honest summary is that caffeine can contribute to acne through several indirect pathways, but calling it a “cause” overstates what the current evidence supports.