Researchers studied 504 people with type 2 diabetes to see if eating prebiotic foods (foods that feed good bacteria in your gut) could help improve their health numbers. They found that eating soybeans, bananas, honey, and green peas was connected to better cholesterol levels, kidney function, and blood pressure. While these results are encouraging, the study only shows that these foods are linked to better health—not that they directly cause the improvements. More research is needed to understand exactly how these foods help people with diabetes.

The Quick Take

  • What they studied: Whether eating prebiotic foods (foods that contain fiber and special compounds that help good gut bacteria grow) helps people with type 2 diabetes manage their blood sugar, cholesterol, kidney function, and blood pressure.
  • Who participated: 504 adults with type 2 diabetes from Iran, with an average age of about 55 years old. About 45% were men and 55% were women.
  • Key finding: People who ate more soybeans had lower bad cholesterol (LDL), those who ate more bananas had better kidney function, and those who ate honey or green peas had lower blood pressure. These connections were small but statistically significant, meaning they’re unlikely to be due to chance.
  • What it means for you: Adding more soybeans, bananas, honey, and green peas to your diet may help improve some of your diabetes-related health numbers. However, this study only shows these foods are connected to better health—it doesn’t prove they cause the improvements. Talk to your doctor before making major diet changes, especially if you take diabetes medications.

The Research Details

This was a cross-sectional study, which means researchers looked at a group of people at one point in time rather than following them over months or years. The 504 participants with type 2 diabetes answered detailed questions about what they ate (using a 148-item food list) and had blood tests done to measure their fasting blood sugar, cholesterol levels, and kidney function. Researchers also measured their height, weight, and blood pressure.

The scientists used statistical methods to look for connections between how much prebiotic food people ate and their health numbers. They adjusted their analysis to account for other factors that might affect the results, like age, gender, and other health conditions. They considered a result important if the probability of it happening by chance was less than 5%.

This type of study is useful for finding patterns and connections, but it’s like taking a snapshot rather than watching a movie—it shows what’s happening at one moment but can’t prove that one thing causes another.

Cross-sectional studies are a good first step for discovering which foods might be helpful for people with diabetes. By looking at many people at once, researchers can spot patterns that might be worth studying more carefully. This approach is practical and affordable, making it useful for exploring new ideas before investing in longer, more expensive studies.

This study has several strengths: it included a fairly large number of participants (504), used a detailed food questionnaire, and measured actual blood markers rather than just asking people how they felt. However, because it’s a snapshot study, we can’t be sure the foods caused the improvements—people who eat more healthy foods might also exercise more or take better care of themselves in other ways. The connections found were small to moderate in strength, suggesting the foods may have a modest effect. The study was conducted in Iran, so results might be somewhat different in other populations.

What the Results Show

The study found four main connections between prebiotic foods and improved health markers in people with type 2 diabetes. First, people who ate more soybeans had lower levels of LDL cholesterol (the ‘bad’ cholesterol that can clog arteries). Second, those who ate more bananas had lower blood urea nitrogen (BUN), which is a sign of better kidney function. Third, people who consumed honey had both lower systolic blood pressure (the top number) and diastolic blood pressure (the bottom number). Fourth, eating more green peas was also linked to lower diastolic blood pressure.

All of these connections were statistically significant, meaning they’re unlikely to have happened by random chance. However, the strength of these connections was modest—the foods appear to have a small to moderate effect rather than a dramatic one. For example, the connection between soybean eating and LDL cholesterol had a correlation of -0.110, which means the relationship exists but isn’t extremely strong.

These findings suggest that adding these specific prebiotic foods to a diabetes diet might help with managing several important health markers at once. The fact that different foods helped different health measures suggests that eating a variety of prebiotic foods might provide broader benefits.

While the study focused on the four main findings above, the researchers also measured other health markers. The fact that multiple foods showed benefits for different health measures suggests that prebiotic foods as a group might be helpful for people with diabetes, rather than just one or two specific foods. The study also looked at whether the amount of prebiotic food eaten mattered—generally, people who ate more of these foods showed stronger connections to better health numbers, though the differences were small.

Previous research has shown that foods high in fiber and prebiotics can help with blood sugar control and heart health in people with diabetes. This study adds to that knowledge by looking at specific prebiotic foods in a large group of diabetic patients. The findings align with what scientists already know about how fiber and prebiotics work—they feed good bacteria in your gut, which can help reduce inflammation and improve how your body processes cholesterol and blood pressure. However, most previous studies were done in Western countries, so this research from Iran helps show that these benefits might apply to different populations.

This study has several important limitations to keep in mind. First, because it’s a snapshot study, we can’t prove that eating these foods actually caused the health improvements—people who eat more healthy foods might also exercise more or have other healthy habits. Second, the study only included people from one region of Iran, so the results might not apply to everyone everywhere. Third, the connections found were modest in strength, suggesting the foods have a small effect rather than a large one. Fourth, the study relied on people remembering what they ate, which can be inaccurate. Finally, the researchers couldn’t account for all possible factors that might affect the results, such as medications people were taking or how much they exercised.

The Bottom Line

Based on this research, it appears reasonable to include more soybeans, bananas, honey, and green peas in your diet if you have type 2 diabetes—these foods are nutritious and this study suggests they may help with some health markers. However, this should be done as part of an overall healthy diet, not as a replacement for diabetes medications or medical care. The evidence is moderate in strength, meaning these foods likely help but aren’t a cure or complete solution. Always talk to your doctor or dietitian before making significant changes to your diet, especially if you take diabetes medications, since some foods can interact with medications.

People with type 2 diabetes who are looking for ways to improve their health through diet should pay attention to these findings. This is especially relevant for people interested in functional foods (foods that provide health benefits beyond basic nutrition). However, people with kidney disease should be cautious about bananas since they’re high in potassium. People with honey allergies or sensitivities should obviously avoid honey. If you don’t have diabetes, these foods are still healthy to eat, but this study doesn’t tell us whether they’d have the same benefits for people without diabetes.

If you start eating more of these prebiotic foods, you shouldn’t expect immediate changes. Blood pressure might improve within a few weeks to a few months of consistent dietary changes. Cholesterol and kidney function markers typically take longer to change—usually several weeks to a few months of regular healthy eating. However, individual results vary widely depending on your overall diet, exercise habits, medications, and genetics. It’s important to have your health markers checked regularly by your doctor to see if dietary changes are helping.

Want to Apply This Research?

  • Track daily servings of prebiotic foods (soybeans, bananas, honey, green peas) and log weekly blood pressure readings if you have a home monitor. Aim for at least one serving of each food type per week and track any changes in your energy levels and how you feel.
  • Set a goal to add one prebiotic food to your meals each day. For example: add soybeans to salads on Monday, eat a banana as a snack on Tuesday, add honey to tea on Wednesday, and include green peas in dinner on Thursday. Use the app to plan meals and get reminders to include these foods.
  • Create a weekly check-in where you log how many servings of prebiotic foods you ate and note any changes in how you feel. If you have access to blood pressure readings or lab work, log those monthly to track changes over time. Set a reminder to discuss your dietary changes with your doctor every 3 months to see if your health markers are improving.

This research shows connections between eating certain foods and better health markers in people with type 2 diabetes, but it does not prove that these foods cause the improvements. This study is not a substitute for medical advice, diagnosis, or treatment from your healthcare provider. Before making significant changes to your diet, especially if you take diabetes medications or have other health conditions, please consult with your doctor or a registered dietitian. Some foods may interact with medications or be unsuitable for certain medical conditions. Individual results vary, and what works for one person may not work for another. This information is for educational purposes only and should not be used to replace professional medical guidance.