Researchers discovered that what you eat might change the bacteria living in your gut, which could affect whether you develop eczema (a skin condition that causes itching and redness). Scientists studied mice with eczema and 102 people with eczema, comparing their diets and gut bacteria. They found that people eating more vegetables and fruits while eating fewer refined grains had different gut bacteria than people without eczema. This suggests that food choices might influence your gut health, which then affects your skin health. The study is early-stage research that opens doors for future treatments involving diet and gut health.

The Quick Take

  • What they studied: Whether the foods people eat change the bacteria in their gut, and if those changes are connected to eczema (a common skin condition that causes itching and inflammation)
  • Who participated: 102 people diagnosed with eczema and 102 people without eczema who were matched by age and gender, plus mice that were given eczema in a laboratory
  • Key finding: People with eczema ate less refined grains (like white bread and processed foods) and more vegetables and fruits compared to people without eczema. These different eating patterns were linked to changes in the types and amounts of bacteria in their gut.
  • What it means for you: Eating more plant-based foods like vegetables and fruits while reducing refined grains might help keep your gut bacteria healthier, which could potentially help with eczema. However, this is early research and more studies are needed before doctors can recommend this as a treatment. Talk to your doctor before making major diet changes, especially if you have eczema.

The Research Details

The researchers used two approaches to understand the connection between food, gut bacteria, and eczema. First, they created eczema in laboratory mice and then looked at how their skin changed, their immune system response, and their gut bacteria. Second, they recruited 102 people with diagnosed eczema and 102 people without eczema who were similar in age and gender. Both groups answered detailed questions about what they ate and provided stool samples so scientists could identify and count the different bacteria in their guts.

The researchers compared the gut bacteria between people with and without eczema, looking at how many different types of bacteria each person had and what those bacteria do. They also analyzed the eating patterns of both groups to see if there were differences in what they ate. Finally, they looked for connections between the foods people ate, the bacteria in their guts, and whether they had eczema.

This research approach is important because it combines evidence from both animals and humans. Animal studies help scientists understand how things work in a controlled setting, while human studies show whether those findings actually apply to real people. By studying both, the researchers could see if the same patterns appeared in both mice and people, which makes the findings more believable. The detailed food questionnaires and bacteria analysis allowed them to find specific connections between diet and gut health.

This study has both strengths and limitations. The strength is that it included a good number of human participants (102 with eczema and 102 without) who were carefully matched to be similar except for eczema status. The researchers also used modern scientific methods to identify bacteria. However, this is a snapshot study, meaning they looked at people at one point in time rather than following them over months or years. This makes it harder to prove that diet actually causes the gut bacteria changes, rather than just being associated with them. The researchers themselves note that these findings are exploratory and need to be tested in future studies.

What the Results Show

In the mice with eczema, scientists found that their skin became thicker and more inflamed compared to healthy mice. The mice with eczema also had higher levels of a protein called IgE in their blood (about 3 times higher), which is a sign of allergic and inflammatory responses.

When looking at gut bacteria, mice with eczema had different bacterial communities compared to healthy mice. Specifically, they had fewer of certain common bacteria (Firmicutes and Bacteroidota) but more of others (Actinobacteriota and Bifidobacterium).

In the human study, people with eczema ate significantly less refined grains (about 24 grams less per day) and more vegetables and fruits (about 38 grams more per day) compared to people without eczema. These dietary differences were strongly connected to differences in their gut bacteria. People with eczema had less diverse gut bacteria and had changes in the bacteria’s ability to break down carbohydrates and amino acids (building blocks of protein).

The research revealed that the bacteria in people with eczema had reduced ability to perform important functions like breaking down carbohydrates, processing amino acids, and producing energy. These are important jobs that gut bacteria normally do to keep our bodies healthy. The study also showed that the connection between diet and gut bacteria was consistent between the mouse studies and the human studies, suggesting this pattern might be real and important.

Previous research has shown that eczema is connected to changes in gut bacteria, but scientists didn’t fully understand which foods might cause these changes. This study adds new information by identifying specific dietary patterns (eating less refined grains and more plants) that appear to be connected to these bacterial changes. The findings fit with other research showing that plant-based foods are generally good for gut health, but this is the first study to specifically connect these dietary patterns to eczema.

This study has several important limitations. First, it only looked at people at one moment in time, so we can’t prove that changing your diet will actually change your bacteria or improve eczema. Second, the study relied on people remembering what they ate, which isn’t always accurate. Third, the study was relatively small (102 people in each group), so the findings might not apply to everyone. Fourth, the researchers couldn’t prove that the gut bacteria changes actually cause eczema—they only found that they’re connected. Finally, the study couldn’t account for all the other factors that might affect both diet and eczema, like stress, sleep, or genetics.

The Bottom Line

Based on this early-stage research, eating more vegetables, fruits, and whole grains while reducing refined grains (like white bread and processed foods) may support healthier gut bacteria. However, confidence in this recommendation is moderate because this is exploratory research. Anyone with eczema should talk to their doctor or a registered dietitian before making major diet changes. This research should not replace medical treatment for eczema prescribed by a doctor.

This research is most relevant to people who have eczema or are at risk for developing it. It may also interest people who want to improve their gut health in general. However, people with severe eczema should not rely on diet changes alone—they should continue working with their doctor on treatment. People without eczema don’t need to make changes based on this single study.

If someone were to change their diet based on these findings, it would likely take several weeks to months to see changes in gut bacteria and potentially longer to see effects on skin health. Gut bacteria can change relatively quickly (within weeks) when diet changes, but skin conditions like eczema typically improve more slowly. Realistic expectations would be to see gradual improvements over 2-3 months if diet changes are going to help.

Want to Apply This Research?

  • Track daily servings of vegetables and fruits (aim for 5+ servings) and refined grain intake (track grams of white bread, pastries, and processed foods). Also note any changes in eczema symptoms like itching, redness, or skin thickness on a weekly basis.
  • Start by adding one extra serving of vegetables or fruits to one meal per day, and replace one refined grain item (like white bread) with a whole grain alternative (like whole wheat bread). Make these small, sustainable changes rather than overhauling your entire diet at once.
  • Keep a weekly log of your diet focusing on plant foods and refined grains, and rate your eczema symptoms on a scale of 1-10 each week. After 8-12 weeks, review whether your symptoms improved alongside your dietary changes. Share this information with your doctor to discuss whether diet modifications are helping your specific situation.

This research is exploratory and early-stage. The findings suggest a possible connection between diet, gut bacteria, and eczema but do not prove that changing your diet will treat or prevent eczema. This information should not replace medical advice from your doctor or dermatologist. If you have eczema, continue following your doctor’s treatment plan. Before making significant dietary changes, especially if you have a medical condition, consult with your healthcare provider or a registered dietitian. Individual results may vary, and what works for one person may not work for another.