Does diabetes make you more likely to catch infections?
Yes. In a study of 115,841 people, those across the entire diabetes spectrum had a much higher risk of nearly every type of infection. That higher risk showed up even in people with prediabetes, before full diabetes ever set in.
Most people think of diabetes as a problem with blood sugar, eyes, kidneys, and nerves. Infections rarely make the list. But this large study found that high blood sugar leaves the body open to a strikingly wide range of infections. Researchers looked at 1,401 separate infections, and people with diabetes had elevated risk for the vast majority of them. The pattern held across type 1 diabetes, type 2 diabetes, and even prediabetes, the early stage when blood sugar is higher than normal but not yet in the diabetes range.
What the data show
The numbers are hard to ignore. Researchers studied 9,476 people with type 1 diabetes, 74,270 with type 2 diabetes, and 32,095 with prediabetes. They then compared each group to people without diabetes. Across every category of infection, grouped by organ system and by type of germ, all three diabetes groups carried a multifold higher risk.
When the team broke this down into individual infections, the breadth was remarkable. They found elevated risk for 880 infections in type 1 diabetes, 1,047 in type 2 diabetes, and 991 in prediabetes. Some risk ratios reached striking magnitudes. The danger was not limited to infections doctors already link to diabetes, such as mucormycosis, a rare and aggressive fungal infection. It also extended to surprising ones, like West Nile virus encephalitis, a brain infection spread by mosquitoes. Of all the categories, cardiovascular infections, those affecting the heart and blood vessels, carried the highest combined risk.
Dr. Kumar’s Take
What strikes me about this study is the sheer scope. We have long known that diabetes raises the risk for a handful of well-known infections, but seeing elevated risk across more than a thousand of them reframes how I think about the disease. Infection is not a side issue in diabetes care, it belongs near the center.
The prediabetes finding is the part I want patients to hear. Many people treat prediabetes as a warning that can wait. This study suggests the body is already paying a price before the official diagnosis arrives. That is a strong argument for acting early. I should add the usual caution: this is one large database from a single health system, and the results show a link, not proof that diabetes directly causes each infection. Still, the signal is loud and consistent.
How the study was done
The researchers used a method called a Bayesian approach, which is a way of weighing many connected factors at once instead of looking at one cause and one effect in isolation. Real patients are complicated. They often have several conditions at the same time, and their records are incomplete. Older, simpler statistics can miss these tangled relationships.
The Bayesian framework let the team account for these overlapping health problems and still produce risk ratios that could be compared directly across type 1 diabetes, type 2 diabetes, and prediabetes. They drew on a large hospital and clinic database covering roughly 1.5 million patients over about three decades. This scale is what allowed them to study so many rare infections at once, something smaller studies simply cannot do.
Who faces the highest risk
The study found that risk was not spread evenly. Infection vulnerability differed by age, sex, ethnicity, ancestry, and even insurance status. In other words, social and demographic factors shaped how exposed a person was, on top of their diabetes itself.
These gaps matter for care. They suggest that some groups may need extra attention with prevention, such as timely vaccines and faster treatment when an infection starts. The authors frame infection prevention, through vaccination, prompt treatment, and good blood sugar control, as an overlooked pillar of diabetes care that deserves far more focus than it currently gets.
Practical Takeaways
- If you have prediabetes or diabetes, talk with your doctor about staying current on recommended vaccines, including flu, pneumonia, and others your doctor suggests, since infection risk is higher even in the prediabetes stage.
- Keep your blood sugar in your target range as best you can, because better glycemic control is tied to lower infection risk in this and earlier research.
- Do not brush off early signs of infection like fever, a wound that will not heal, or pain when urinating, and seek care promptly rather than waiting it out.
- Treat a prediabetes diagnosis as a reason to act now, not later, since the body appears to face higher infection risk before full diabetes develops.
Related Studies and Research
- Can you prevent type 2 diabetes with lifestyle changes? A Finnish study says yes
- Omega-3 fatty acids and type 2 diabetes risk: what the latest research reveals
- Does rosuvastatin prevent heart disease in healthy people with intermediate risk? A look at the HOPE-3 trial
- Do statins really help prevent heart disease? A closer look at the evidence
FAQs
Why does diabetes raise the risk of so many infections?
High blood sugar can weaken several of the body’s defenses at once. It can blunt how well infection-fighting white blood cells work, slow wound healing, and reduce blood flow to small vessels, which makes it easier for germs to take hold. Because these effects are body-wide rather than tied to one organ, they help explain why the higher risk shows up across so many different infections rather than just a few. This study did not test each mechanism directly, but its breadth fits what we already know about how high glucose affects the immune system.
Does prediabetes really carry infection risk, or only full diabetes?
This study found elevated risk for 991 individual infections in people with prediabetes, which shows the danger begins before a full diabetes diagnosis. That is an important shift in thinking, since prediabetes is often treated as a low-stakes warning. The finding suggests that the changes raising infection risk are already underway during this earlier stage. It is one more reason to take prediabetes seriously and work on lifestyle changes early.
What can I do to lower my infection risk if I have diabetes?
The most practical steps are staying up to date on vaccines, keeping your blood sugar near your target range, and getting care quickly when an infection starts. Good daily habits help too, such as foot checks if you have nerve problems, careful wound care, and regular checkups. None of these guarantee you will avoid infection, but together they meaningfully lower your odds. Your own doctor can tailor a plan to your specific type of diabetes and health history.
Bottom Line
This large study reframes diabetes as far more than a blood sugar problem. Across 115,841 people, those with type 1 diabetes, type 2 diabetes, and even prediabetes faced a higher risk of nearly every infection studied, from common ones to rare and dangerous ones. The risk started early, varied across groups, and was strongest for infections of the heart and blood vessels. The clear message is that infection prevention, through vaccines, prompt treatment, and blood sugar control, deserves a central place in diabetes care.
