Researchers discovered that people with type 2 diabetes who develop kidney problems have much lower levels of a special protein called BDNF that helps protect the brain and nerves. This study compared three groups: healthy people, people with diabetes, and people with diabetes and kidney disease. They found that the kidney disease group had the lowest BDNF levels, and these levels were connected to vitamin deficiencies and inflammation in the body. This finding suggests that BDNF could be a useful marker to help doctors identify and monitor kidney disease in diabetic patients, and that maintaining good nutrition and controlling inflammation might be important for protecting this protein.

The Quick Take

  • What they studied: Whether a brain-protecting protein called BDNF is lower in people with diabetes who develop kidney disease, and how it connects to vitamins, minerals, and inflammation
  • Who participated: Three groups of people: healthy individuals with no diabetes, people with type 2 diabetes without kidney problems, and people with type 2 diabetes who developed kidney disease. The exact number of participants wasn’t specified in the available information
  • Key finding: People with diabetes and kidney disease had BDNF levels of 27.23 ng/mL, compared to 34.1 ng/mL in those with just diabetes and 42.1 ng/mL in healthy people. This protein was also linked to low levels of vitamins D, B12, and folate, plus minerals like zinc
  • What it means for you: If you have type 2 diabetes, maintaining good nutrition (especially vitamins and minerals) and controlling inflammation might help protect this important brain protein. However, this is early research, and you should discuss any concerns about kidney health with your doctor rather than making changes based on this study alone

The Research Details

This was a case-control study, which is like comparing two groups of people to find differences. Researchers took blood samples from three groups: healthy people (the control group), people with type 2 diabetes without kidney problems, and people with type 2 diabetes who had developed kidney disease. They measured a special protein called BDNF in the blood using a laboratory technique called ELISA, which is like a chemical test that can detect very small amounts of proteins. They also measured other things in the blood including vitamins (D, B12, and folate), minerals (zinc and calcium), inflammation markers (IL-6 and IL-12), cholesterol, and kidney function markers (creatinine and urea).

Case-control studies are useful for finding connections between a disease and different factors in the body. By comparing healthy people to those with diabetes and kidney disease, researchers can identify what’s different and might be important. This approach helps scientists understand whether certain proteins or nutrients might be warning signs of kidney disease developing

This study was published in PeerJ, a peer-reviewed scientific journal, which means other experts reviewed the research before publication. The researchers measured BDNF using a standard laboratory technique (ELISA) that is reliable and widely used. However, the study didn’t specify how many people participated, which makes it harder to know how confident we should be in the results. The very high accuracy score (0.938) for using BDNF to identify kidney disease is promising but should be confirmed in larger studies

What the Results Show

The main finding was that BDNF levels dropped significantly as kidney disease developed. Healthy people had the highest levels (42.1 ng/mL), people with just diabetes had lower levels (34.1 ng/mL), and people with diabetes and kidney disease had the lowest levels (27.23 ng/mL). This suggests that kidney disease causes an additional drop in this protective protein beyond what diabetes alone causes. The researchers also found that BDNF levels were connected to how well blood sugar was controlled and to kidney function markers like creatinine. In people with just diabetes, BDNF was related to blood sugar control, but in those with kidney disease, the relationship was different, suggesting the kidney disease changes how this protein behaves.

The study found that low BDNF levels were connected to deficiencies in several important nutrients: vitamin D, vitamin B12, and folate (a B vitamin). Low zinc levels were also associated with lower BDNF. Additionally, markers of inflammation in the blood (specifically IL-6 and IL-12) were higher when BDNF was lower. This suggests that poor nutrition and increased inflammation might work together to reduce this protective protein

Previous research had shown that BDNF levels are generally lower in people with diabetes compared to healthy people. This study adds important new information by showing that kidney disease causes an even bigger drop in BDNF. The connection between BDNF and nutritional deficiencies is relatively new and suggests that nutrition might be more important than previously thought in protecting this protein

The study didn’t report the total number of participants, making it difficult to assess how reliable the results are. The study was designed to find connections between variables but cannot prove that low BDNF causes kidney disease or that improving nutrition will raise BDNF levels. The results need to be confirmed in larger studies with more participants. Additionally, this study only looked at people with type 2 diabetes, so the results may not apply to people with type 1 diabetes or other conditions

The Bottom Line

If you have type 2 diabetes, focus on maintaining adequate levels of vitamins D, B12, and folate, as well as zinc, through diet or supplements as recommended by your doctor (moderate confidence based on this single study). Regular monitoring of kidney function through blood tests and urine tests is important for all diabetic patients (high confidence based on established medical practice). Work with your healthcare team to control blood sugar and reduce inflammation through diet, exercise, and medication if needed (high confidence). Do not make supplement decisions based solely on this research without consulting your doctor

This research is most relevant to people with type 2 diabetes, especially those concerned about kidney health. It may also interest people with a family history of diabetes or kidney disease. Healthcare providers managing diabetic patients should be aware of these findings. This research is less immediately relevant to people without diabetes, though maintaining good nutrition is important for everyone

If nutritional deficiencies are contributing to low BDNF, it could take several weeks to months of consistent supplementation and dietary improvements to see changes in blood levels. However, this study doesn’t tell us how quickly BDNF levels might improve with better nutrition, so realistic expectations should be discussed with your doctor

Want to Apply This Research?

  • Track daily intake of vitamin D, B12, folate, and zinc through food or supplements. Users can log meals and supplement doses, with the app calculating whether they’re meeting recommended daily amounts. This creates a concrete way to monitor nutritional status
  • Set a daily reminder to consume foods rich in these nutrients (fortified cereals for B vitamins, fatty fish for vitamin D, leafy greens for folate, nuts and seeds for zinc) or take supplements as prescribed. Users can check off completion each day to build consistency
  • Users with diabetes should log their regular blood test results (especially kidney function markers like creatinine and blood sugar control like HbA1c) when they receive them from their doctor. The app can show trends over time and help users see connections between their nutrition tracking and medical test results, encouraging them to discuss findings with their healthcare provider

This research is preliminary and should not replace medical advice from your healthcare provider. BDNF is a research marker and is not routinely measured in clinical practice. If you have type 2 diabetes or concerns about kidney health, consult your doctor before making changes to your diet, supplements, or medications. Do not use this information to self-diagnose or self-treat kidney disease. Regular monitoring by a healthcare professional is essential for managing diabetes and preventing complications. Any supplement decisions should be made in consultation with your doctor or registered dietitian, as supplements can interact with medications and may not be appropriate for everyone.