How Your Gut Health Affects Your Skin (And What to Do About It)

Your skin breaks out the week before your period. You switch to a gentle cleanser, add niacinamide, cut dairy. Nothing changes. Meanwhile you're bloated, your digestion is unpredictable, and the afternoon energy crash arrives like clockwork.

That may not be a coincidence. Your gut and skin talk to each other through inflammation, immunity and nutrient absorption, and researchers call this link the gut-skin axis. A 2018 review of the gut-skin axis links gut bacteria imbalances to acne, psoriasis, and eczema, though the authors say the mechanisms are not yet fully understood. The link may run the other way too: chronic skin inflammation may affect your gut bacteria.

Here's the short version. An imbalance in gut bacteria may drive low-grade inflammation that may show up as acne or eczema flares. When the intestinal lining is compromised, bacteria and their by-products can reach your bloodstream and add to that inflammation. And gut conditions that damage the lining can cut how well you absorb the nutrients your skin needs for repair.

The Gut-Skin Axis Works Through Three Main Pathways

A large share of your immune cells sit in and around your gut lining, so what happens there shapes inflammation across your body. When antibiotics, processed food or chronic stress throw your gut bacteria out of balance, inflammatory signals can travel through your bloodstream to your skin.

Lipopolysaccharides are inflammatory molecules from the outer wall of certain gut bacteria. When your intestinal barrier is disturbed (often called leaky gut), these molecules can get into circulation and set off inflammation. Researchers think this may feed into inflammatory skin problems, including hormonal acne patterns, but it hasn't been proven in people.

Beneficial gut bacteria also ferment fiber into short-chain fatty acids such as butyrate, which help calm inflammatory immune responses. Without enough of these bacteria, you lose some of that protection. The gut-skin link shows up clearly in rosacea: a 2008 study of 113 people with rosacea found small intestinal bacterial overgrowth in 46% of them, compared with 5% of healthy controls, and clearing the overgrowth with an antibiotic cleared or greatly improved the skin in most of those treated.

Nutrient Absorption Problems Show Up on Your Skin

Gut conditions that damage or inflame the lining, like celiac disease and inflammatory bowel disease, can reduce how well you absorb vitamin A and zinc. Your skin needs both for cell turnover and wound healing. Vitamin A deficiency can leave skin rough and bumpy.

Low zinc can slow wound healing and affect the skin. Vitamin D is fat-soluble, so poor fat absorption can lower your levels of it too.

Some gut bacteria also make B vitamins, which your skin uses for barrier repair, but how much this adds to what you get from food is still unclear. Since skin and gut problems often turn up together, it's worth knowing the signs of a damaged skin microbiome too.

What Actually Fixes the Gut-Skin Connection

Probiotics may help, but the evidence is early and the effects depend on the specific strain. In a 2024 placebo-controlled trial in people aged 12 to 30 with acne, a daily capsule of Lacticaseibacillus rhamnosus plus spirulina improved acne severity more than placebo over 12 weeks. That result applies to that product, not to probiotics in general. If you try one, pick a product that names its exact strains and has been studied for the problem you want to treat.

Prebiotic fiber feeds the beneficial bacteria you already have. Jerusalem artichoke, garlic, onions and green bananas contain inulin and resistant starch, which those bacteria feed on. Start small, because too much too fast can cause gas and bloating.

Bone broth is often recommended for gut repair, but there's little direct research showing it heals the intestinal lining. The stronger evidence is for glutamine, an amino acid: in a 2019 placebo-controlled trial in people with irritable bowel syndrome after a gut infection, 5 grams of glutamine three times a day for 8 weeks reduced symptoms and brought raised gut permeability back to normal. That was a specific group with measured gut permeability, so talk to your doctor before supplementing on your own.

If you suspect a food is making your skin worse, test that one food rather than cutting out whole food groups. The American Academy of Dermatology notes that small studies link cow's milk and high-glycemic foods like white bread and sugary drinks to more acne, but the evidence is mixed. It suggests avoiding a suspected trigger for a while and watching whether your breakouts change.

How Long It Takes

Gut bacteria can shift within days of changing what you eat, but they tend to shift back when you return to old habits. Sticking with the changes matters more than a short reset. Your skin microbiome and skin cells renew over weeks, not days, so expect visible skin changes to take a few months.

Week one won't look like much. Watch your digestion first: less bloating, more regular bowel movements, steadier energy. If your skin responds, calmer inflammation and fewer new breakouts tend to come before any change in texture or tone.

FAQ

Can probiotics make acne worse initially?

There's no good evidence that probiotics cause a breakout phase while gut bacteria rebalance. The more common early side effects are mild gas and bloating. If your skin gets worse after starting a probiotic, stop it and talk to your doctor or dermatologist.

How do I know if leaky gut is causing my skin problems?

There's no reliable test for it yet. Zonulin blood tests are often sold as a leaky gut test, but a 2019 study of commercial zonulin tests found they were picking up other proteins and can't be used to judge gut permeability. Signs worth raising with a doctor include skin issues that worsen with specific foods, digestive symptoms alongside breakouts, and stress-triggered skin flares. A doctor can test for specific conditions such as celiac disease or small intestinal bacterial overgrowth.

Do digestive enzymes help with skin problems?

Prescription digestive enzymes improve nutrient absorption in people whose pancreas doesn't make enough of its own, which a doctor can diagnose. There's no good evidence that over-the-counter enzymes improve skin. If you have greasy or pale stools, undigested food in your stool, or weight loss you can't explain, see a doctor rather than self-treating.