A sweat gland test called SUDOSCAN detects nerve damage from type 1 diabetes in nearly twice as many people as traditional screening methods, according to Gram Research analysis of a 2026 study of 264 patients. The test found nerve problems in 46% of participants versus 22% with standard screening, and people with abnormal sweat function were 4.3 times more likely to have nerve damage. This objective test could enable earlier detection and treatment of diabetic nerve complications.
Researchers in India discovered that a simple sweat gland test can detect nerve damage from diabetes before traditional screening methods catch it. The study of 264 young adults with type 1 diabetes found that nearly half showed sweat gland problems, even when standard nerve tests appeared normal. This “sudomotor” test, which measures how well sweat glands work, was 4.3 times better at identifying people at risk for serious nerve damage. The findings suggest this objective test could help doctors catch diabetic nerve damage much earlier, potentially preventing complications before they become severe.
Key Statistics
A 2026 study of 264 type 1 diabetes patients published in the Journal of Diabetes Investigation found that sweat gland testing (SUDOSCAN) detected nerve damage in 46.2% of participants, compared to only 22.3% detected by traditional screening methods.
According to research reviewed by Gram, people with abnormal sweat gland function (electrochemical skin conductance below 60 microsiemens) were 4.3 times more likely to have clinical diabetic nerve damage compared to those with normal sweat function.
In a 2026 study of 264 type 1 diabetes patients, the SUDOSCAN sweat gland test had a sensitivity of 72.8% for detecting clinical nerve damage, meaning it correctly identified about 7 out of 10 people with actual nerve problems.
Among 205 type 1 diabetes patients with normal traditional nerve screening, a 2026 study found that 38.5% had hidden early nerve damage detected by sweat gland testing, suggesting substantial underdiagnosis with current methods.
The Quick Take
- What they studied: Whether a sweat gland test (SUDOSCAN) can detect early nerve damage from type 1 diabetes better than traditional screening methods
- Who participated: 264 young adults with type 1 diabetes (average age 26 years, about half male) from a hospital in Pune, India who had lived with diabetes for an average of 13 years
- Key finding: The sweat gland test detected nerve damage in 46% of participants, compared to only 22% detected by traditional screening. People with abnormal sweat gland function were 4.3 times more likely to have nerve damage.
- What it means for you: If you have type 1 diabetes, this test could catch nerve damage years before you notice symptoms, allowing earlier treatment. However, this is one study and more research is needed before it becomes standard screening.
The Research Details
Researchers recruited 264 people with type 1 diabetes and gave them two different nerve damage tests on the same day. The first test was the traditional screening method (MNSI), which involves physical exams and questions about symptoms. The second was a newer test called SUDOSCAN that measures how well sweat glands conduct electricity—a sign of healthy nerve function.
Participants were then sorted into three groups: those with obvious nerve damage on traditional testing, those with normal traditional tests but abnormal sweat gland function (early/hidden damage), and those completely normal on both tests. The researchers compared how well each test detected nerve damage and looked for patterns in who developed problems.
Diabetic nerve damage often develops silently without symptoms, making early detection crucial. By the time people notice problems like numbness or pain, significant damage has already occurred. This study tested whether measuring sweat gland function—one of the earliest signs of nerve damage—could catch problems years earlier than current methods.
This was a well-designed prospective study (following people forward in time rather than looking backward) with a reasonable sample size of 264 participants. All participants received both tests simultaneously, reducing bias. The study was conducted at a major hospital with established diabetes research programs. However, the study included only type 1 diabetes patients from one region of India, so results may not apply equally to all populations or to type 2 diabetes.
What the Results Show
The sweat gland test (SUDOSCAN) detected nerve damage in 46.2% of participants, while the traditional screening method caught only 22.3%. This means the sweat test found more than twice as many people with nerve problems. The sweat test had a sensitivity of 72.8%, meaning it correctly identified about 7 out of 10 people who actually had nerve damage.
Most importantly, people whose sweat glands weren’t working properly (measured by electrical conductance below 60 microsiemens) were 4.3 times more likely to have clinical nerve damage compared to those with normal sweat function. This strong relationship suggests sweat gland testing could be a powerful screening tool.
Among the 205 participants who had normal traditional screening, the sweat test found hidden nerve damage in 38.5% of them. These people with early, undetected nerve damage tended to be younger, had diabetes for shorter periods, and were more likely to have vitamin D deficiency and anemia.
The study identified important patterns in who develops early nerve damage. Younger age, shorter diabetes duration, vitamin D deficiency, anemia, and existing blood vessel complications were all associated with sweat gland dysfunction. This suggests multiple factors beyond blood sugar control affect nerve health. The finding that younger people with shorter diabetes duration showed early nerve damage was surprising and suggests aggressive screening may be needed even in newly diagnosed patients.
Previous research has shown that nerve damage in diabetes develops in stages, with sweat gland problems appearing first. This study confirms that observation and demonstrates that SUDOSCAN can reliably measure this early stage. Unlike previous studies that were smaller or conducted in different populations, this research provides strong evidence from a well-characterized group of type 1 diabetes patients that the sweat test outperforms traditional screening.
The study included only type 1 diabetes patients, so results may not apply to type 2 diabetes. All participants were from one hospital in India, so the findings may not represent all populations equally. The study didn’t follow participants over time to see if those with early sweat gland problems actually developed worse nerve damage later. The SUDOSCAN device is expensive and not widely available, which could limit practical use. The study didn’t examine whether early detection and treatment based on sweat testing actually prevents complications.
The Bottom Line
If you have type 1 diabetes, discuss sweat gland testing (SUDOSCAN) with your doctor as a potential screening tool, especially if you’ve had diabetes for several years. This test appears significantly better at catching early nerve damage than traditional screening. However, this is based on one study, so ask your doctor whether this test is available and appropriate for you. Standard screening should continue until more evidence shows this test prevents complications. (Confidence: Moderate—strong evidence for detection, but limited evidence for preventing complications)
People with type 1 diabetes should care most about this research, particularly those who have had diabetes for 10+ years or have other complications. Healthcare providers managing diabetes should consider adding sweat gland testing to their screening protocols. People with type 2 diabetes should note this study doesn’t yet apply to them. Those with early diabetes (newly diagnosed) may also benefit from earlier screening based on these findings.
Sweat gland dysfunction can develop within years of diabetes diagnosis, as shown by the younger participants in this study. Early detection through this test could allow interventions to start years before traditional screening would catch problems. However, it’s unclear how quickly early sweat gland problems progress to clinical nerve damage—this requires longer-term studies.
Frequently Asked Questions
Can a sweat test detect diabetes nerve damage earlier than regular screening?
Yes. A 2026 study of 264 type 1 diabetes patients found sweat gland testing detected nerve damage in 46% of people, versus only 22% with traditional screening. The sweat test identified early nerve problems in 38.5% of patients who appeared normal on standard tests.
What does the SUDOSCAN test measure and how does it work?
SUDOSCAN measures electrochemical skin conductance—how well sweat glands conduct electricity. Sweat gland dysfunction is one of the earliest signs of diabetic nerve damage. The test is objective and non-invasive, making it more reliable than symptom-based screening.
How much more likely are people with abnormal sweat gland function to have nerve damage?
According to a 2026 study of 264 type 1 diabetes patients, people with abnormal sweat gland function were 4.3 times more likely to have clinical diabetic nerve damage compared to those with normal sweat function, making it a strong predictor.
Should I get a sweat gland test if I have type 1 diabetes?
Discuss this with your doctor. This 2026 study shows the test is superior at detecting early nerve damage, but it’s not yet standard screening everywhere. Your doctor can determine if SUDOSCAN is available and appropriate for your situation.
What factors increase the risk of early nerve damage in type 1 diabetes?
A 2026 study found that younger age, shorter diabetes duration, vitamin D deficiency, anemia, and existing blood vessel complications were associated with early sweat gland dysfunction, suggesting multiple factors beyond blood sugar affect nerve health.
Want to Apply This Research?
- If you have access to SUDOSCAN testing, track your electrochemical skin conductance (ESC) score annually. Record the specific number (normal is ≥60 μS) and note any changes. Compare trends over time rather than focusing on single results.
- Use sweat gland test results as motivation to optimize diabetes management. If your test shows early sweat gland problems, work with your doctor to improve blood sugar control, vitamin D levels, and manage anemia—all factors associated with nerve health in this study.
- Establish a baseline sweat gland test if available, then repeat annually. Track alongside traditional nerve screening (MNSI), blood sugar control, vitamin D levels, and hemoglobin levels. Use the app to set reminders for annual testing and to record results, creating a long-term picture of your nerve health.
This research describes a screening tool for detecting diabetic nerve damage and should not be interpreted as medical advice. The study was conducted in type 1 diabetes patients in India and may not apply equally to all populations or type 2 diabetes. SUDOSCAN testing is not yet standard screening in all healthcare settings. Consult with your healthcare provider about appropriate nerve damage screening for your individual situation. This article summarizes research findings but does not replace professional medical diagnosis or treatment recommendations. If you have symptoms of nerve damage (numbness, tingling, pain in feet or hands), seek medical evaluation regardless of screening test results.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.