Scientists are discovering that the bacteria living in your stomach and intestines might play a big role in skin conditions like eczema (atopic dermatitis). When these bacteria are out of balance, it can trigger skin problems and make your immune system overreact. New research suggests that eating the right foods and taking specific probiotics tailored to your body might help restore balance and calm inflamed skin. This personalized nutrition approach combines what we know about gut bacteria with advanced technology to create custom treatment plans for people struggling with severe itching and skin irritation.

The Quick Take

  • What they studied: How bacteria in your gut and the substances they produce affect skin inflammation and eczema, and whether personalized nutrition plans based on your individual bacteria can help treat it
  • Who participated: This is a review article that analyzed existing research rather than testing people directly. Scientists looked at hundreds of studies about gut bacteria, skin health, and immune system function
  • Key finding: The bacteria in your gut produce special chemicals that can calm down your immune system and reduce skin inflammation. When these bacteria are imbalanced, it allows harmful immune reactions that cause itchy, inflamed skin
  • What it means for you: In the future, doctors might be able to test your gut bacteria and recommend specific foods or probiotics designed just for you to help control eczema. This is still emerging science, so talk to your doctor before making major dietary changes

The Research Details

This is a review article, which means scientists read and analyzed many existing studies on the topic rather than conducting their own experiment. The researchers looked at how bacteria in your digestive system communicate with your immune system and skin. They examined the specific pathways and chemical signals involved in this communication, focusing on how certain bacterial metabolites (substances bacteria produce) can either trigger or calm down skin inflammation.

The scientists also explored how personalized nutrition—tailoring diet and probiotics to match your individual bacterial makeup—could be more effective than one-size-fits-all treatments. They discussed using advanced technology like genetic testing and machine learning to identify which foods and supplements would work best for each person’s unique situation.

Understanding how gut bacteria affect skin is important because current eczema treatments often only address the skin itself, not the root cause. If we can fix the bacterial imbalance in the gut, we might prevent skin problems from starting or coming back. This approach could also reduce the need for strong medications with side effects. Personalized nutrition means treatments could be much more effective because they’re designed specifically for your body’s needs.

This is a review of existing research, not a new study with participants, so it summarizes what we already know rather than providing new experimental evidence. The quality depends on which studies the authors included and how carefully they analyzed them. Since this is published in a respected medical journal, the information has been checked by other experts. However, many of the specific treatments discussed are still being researched and aren’t yet standard medical care.

What the Results Show

The research shows that healthy gut bacteria produce short-chain fatty acids (SCFAs)—special chemicals that help calm down immune system overreactions. When people with eczema have an imbalance in their gut bacteria, they produce fewer of these calming chemicals, which allows inflammation to develop in the skin.

Scientists identified several key immune pathways involved in eczema. One important pathway involves a protein called TSLP that triggers immune cells to cause itching and inflammation. Another involves IL-31, which directly causes the itching sensation. Healthy gut bacteria and their metabolites can block these pathways and reduce inflammation.

The research also shows that what you eat directly affects which bacteria live in your gut. Certain foods promote the growth of beneficial bacteria that produce more of the calming chemicals, while other foods feed harmful bacteria that increase inflammation. This means diet isn’t just supporting skin health indirectly—it’s actively shaping the bacterial community that controls immune responses.

The review highlights that different people have different bacterial communities, which explains why the same food or probiotic doesn’t work for everyone. Advanced testing can identify which specific bacteria and foods would benefit each individual. The research also shows that probiotics (beneficial bacteria supplements) work best when they’re chosen based on what’s missing from a person’s specific bacterial makeup. Additionally, the timing and location of treatments matter—delivering nutrients directly to the skin while also fixing gut bacteria imbalance appears more effective than treating just one area.

This research builds on decades of studies showing that eczema involves both skin barrier problems and immune system dysfunction. Previous research focused mainly on treating the skin directly with creams and medications. This new approach adds an important piece: fixing the gut bacteria imbalance that’s driving the immune dysfunction. It represents a shift from treating just symptoms to addressing root causes. Some earlier studies hinted at this connection, but this review brings together the latest evidence showing how powerful this gut-skin connection really is.

This is a review article summarizing other studies, not original research, so it can’t prove cause-and-effect relationships. Many of the specific personalized nutrition treatments discussed are still being tested and aren’t yet proven effective in large groups of people. The technology needed to test individual bacteria and create truly personalized plans is still developing and expensive. Additionally, most research has focused on specific populations, so results might not apply equally to everyone. The review also notes that while the science is promising, we still don’t fully understand all the ways gut bacteria affect skin in every person.

The Bottom Line

If you have eczema, talk to your doctor about testing your gut bacteria before starting probiotics or making major dietary changes (moderate confidence—this is emerging science). Eat a diverse diet rich in fiber, fruits, and vegetables, which feed beneficial bacteria (moderate-to-high confidence based on general health research). Avoid foods that trigger your individual symptoms, which you can identify by keeping a food diary (high confidence). Consider working with a doctor or nutritionist who understands the gut-skin connection rather than self-treating (moderate confidence). Standard eczema treatments remain important while exploring these approaches (high confidence).

People with moderate-to-severe eczema who haven’t found relief with standard treatments should pay attention to this research. Anyone with a family history of eczema, allergies, or autoimmune conditions might benefit from understanding gut health. People interested in preventing eczema before it develops could use this information. However, if you have mild eczema controlled by basic moisturizers, you may not need to pursue these advanced approaches. Always work with your doctor before making changes, especially if you’re taking medications or have other health conditions.

Changes in gut bacteria take time—typically 2-4 weeks to see shifts in bacterial populations after dietary changes, and 4-12 weeks to notice improvements in skin symptoms. Some people might see faster results, while others need longer. Probiotics may take 6-8 weeks to show benefits. This isn’t a quick fix like a topical cream, but the improvements may last longer if you maintain the dietary changes.

Want to Apply This Research?

  • Track daily skin symptoms (itching intensity on a 1-10 scale, redness, dryness) alongside meals and bowel regularity. Note any correlations between specific foods and skin flare-ups. This helps identify your personal triggers and shows whether changes are working
  • Start a food diary within the app to record what you eat and your skin symptoms the next day. Gradually increase fiber intake by adding one new high-fiber food per week (like beans, berries, or whole grains). Add a probiotic-rich food daily (like yogurt or fermented vegetables) and track how your skin responds
  • Use the app to take weekly photos of affected skin areas in consistent lighting to visually track improvement. Create a monthly summary comparing symptom scores, dietary patterns, and skin changes. Share this data with your doctor to refine your personalized approach over time

This article summarizes emerging research on gut bacteria and skin health. It is not a substitute for professional medical advice, diagnosis, or treatment. Atopic dermatitis is a complex condition that requires individualized care from a qualified healthcare provider. Before making significant dietary changes, starting probiotics, or stopping any current treatments, consult with your doctor or dermatologist. Some of the personalized nutrition approaches discussed are still being researched and may not be available or appropriate for everyone. If you experience severe itching, skin infections, or worsening symptoms, seek immediate medical attention.