Researchers tested a special substance from kefir (a fermented milk drink) to see if it could help rats with type 2 diabetes control their blood sugar better. The rats that received high doses of this kefir ingredient showed improved blood sugar control, better insulin sensitivity, and less damage to the cells that produce insulin. The treatment also reduced kidney problems that often come with diabetes. While these results are promising, the study was only done in rats, so scientists need to test it in humans before we know if it will work the same way for people with diabetes.

The Quick Take

  • What they studied: Whether a natural substance found in kefir could help rats with type 2 diabetes control their blood sugar levels and protect the cells that make insulin
  • Who participated: Laboratory rats (about 32 total): some were given diabetes using chemicals and a high-fat diet, while others stayed healthy as a comparison group. All were young male rats about 8 weeks old
  • Key finding: Rats that received high doses of the kefir ingredient had much better blood sugar control and their insulin-producing cells stayed healthier compared to diabetic rats that didn’t receive the treatment
  • What it means for you: This suggests that kefir-derived substances might one day help people with diabetes or prediabetes manage their condition, but we need human studies first to know if it actually works in people. Don’t replace your diabetes medications with kefir without talking to your doctor

The Research Details

Scientists created type 2 diabetes in young rats by feeding them a high-fat diet for 4 weeks, then giving them a chemical injection that damages insulin-producing cells. This mimics how type 2 diabetes develops in humans. Once the rats had diabetes, they divided them into three groups: one group got no treatment, one got a high dose of the kefir ingredient, and one got a low dose. All groups were monitored for 4 weeks while the treated groups received their doses. The researchers also kept a healthy group of rats that never got diabetes to use as a comparison.

The kefir ingredient they tested is called an exopolysaccharide—basically a complex sugar that kefir bacteria naturally produce. The scientists measured blood sugar levels, insulin sensitivity, kidney function, and looked at the health of insulin-producing cells under a microscope to see what changed.

This type of study in animals is important because it allows researchers to test new treatments safely before trying them in humans, and they can measure things in detail that would be harder to study in people.

Animal studies like this help scientists understand how a treatment works in the body before testing it in humans. By using rats with artificially created diabetes that’s similar to human type 2 diabetes, researchers can see if the kefir ingredient actually affects the specific cells and processes involved in blood sugar control. This information helps decide whether it’s worth testing in human clinical trials

This study was published in a peer-reviewed scientific journal, meaning other experts reviewed it before publication. The researchers used a control group of healthy rats for comparison, which strengthens the findings. However, the study was only done in rats, not humans, so results may not translate directly to people. The exact number of rats in each group wasn’t clearly stated in the abstract, which is a minor reporting issue. The study was relatively short (4 weeks of treatment), so we don’t know about long-term effects

What the Results Show

Rats that received the high dose of kefir-derived substance showed significantly better blood sugar control compared to untreated diabetic rats. The treatment worked by increasing a protein called GLUT2 in liver cells, which helps the liver take up more glucose from the bloodstream and store it. This is important because the liver is like the body’s glucose storage warehouse.

The treatment also improved insulin sensitivity, meaning the rats’ bodies responded better to insulin and could use it more effectively. This is a key problem in type 2 diabetes—people’s bodies stop responding well to insulin even though they’re producing it. The kefir ingredient appeared to fix this problem in the rats.

Another major finding was that the treatment protected the insulin-producing cells in the pancreas. These cells are damaged in diabetes, which is why blood sugar gets out of control. The treated rats had healthier, more intact insulin-producing cells compared to untreated diabetic rats.

Finally, the rats that received treatment had less kidney enlargement and a lower kidney-to-body weight ratio, suggesting the treatment may have protected the kidneys from diabetes-related damage.

The study found that the kefir ingredient reduced fat production in the body, which is important because excess fat and high blood sugar often go together in type 2 diabetes. The low-dose treatment showed some benefits but wasn’t as effective as the high dose, suggesting that the amount of treatment matters. The healthy control rats (those without diabetes) remained healthy throughout, confirming that the diabetes was successfully created in the other groups

Previous research has shown that fermented foods like kefir have compounds that may help with blood sugar control, but most studies have been in test tubes or animals. This study adds to that evidence by showing a specific component of kefir (the exopolysaccharide) can help in a realistic animal model of type 2 diabetes. The findings align with other research suggesting that natural compounds from fermented foods might support diabetes management, though human studies are still limited

The biggest limitation is that this was only tested in rats, not humans. Rats’ bodies work differently than human bodies in many ways, so results may not translate directly. The study was relatively short (4 weeks of treatment), so we don’t know if benefits last longer or if problems develop over time. The researchers didn’t test different doses systematically to find the optimal amount. We also don’t know how the kefir ingredient would work alongside standard diabetes medications. Finally, the study doesn’t tell us which specific part of the kefir ingredient is responsible for the benefits

The Bottom Line

Based on this rat study alone, we cannot recommend kefir or kefir supplements as a diabetes treatment for humans. The evidence is promising but preliminary. If you have type 2 diabetes or prediabetes, continue taking your prescribed medications and follow your doctor’s advice. Including fermented foods like kefir as part of a healthy diet may have general health benefits, but don’t use it as a replacement for medical treatment. Wait for human clinical trials before making major changes based on this research

People with type 2 diabetes or prediabetes should be interested in this research as a potential future option, but shouldn’t change their current treatment based on it. Researchers studying natural diabetes treatments should pay attention to these findings. People interested in fermented foods and their health benefits may find this interesting. People with kidney problems related to diabetes might eventually benefit if human studies confirm these results

Even if human studies confirm these findings, it typically takes 5-10 years of research before a new treatment becomes available to the general public. Don’t expect kefir-based diabetes treatments to be widely available soon. If you want to try kefir now, it’s generally safe for most people, but discuss it with your doctor first, especially if you have diabetes or take medications

Want to Apply This Research?

  • If a user wants to explore kefir as a complementary food (with doctor approval), they could track daily kefir consumption (in ounces or servings) alongside their blood sugar readings to see if they notice any personal patterns over 4-8 weeks
  • Users could set a reminder to consume a small serving of kefir daily (if approved by their doctor) and log it in the app, while also tracking how they feel and any changes in energy levels or blood sugar readings
  • Create a long-term tracking dashboard that shows kefir consumption frequency alongside blood sugar trends, weight, and energy levels over months. Include a note that this is exploratory tracking and not a replacement for medical treatment, and encourage users to share results with their healthcare provider

This research was conducted in rats, not humans, so results may not apply to people. Do not use kefir or kefir supplements as a replacement for prescribed diabetes medications or medical treatment. Always consult with your doctor or healthcare provider before making changes to your diabetes management plan or adding supplements to your diet. If you have type 2 diabetes, prediabetes, or kidney disease, discuss any dietary changes with your healthcare team first. This article is for educational purposes only and should not be considered medical advice