Quick answer: diabetes does not appear to make a person automatically “catch” COVID-19 more easily, but it can make COVID-19 more dangerous once infection happens. The relationship also runs in the other direction: COVID-19 infection may worsen blood sugar control and has been linked in research to a higher risk of newly diagnosed diabetes in some people. In other words, diabetes and COVID-19 are not best friends. They are more like two troublemakers who become louder when they sit next to each other.
For people living with type 1 diabetes, type 2 diabetes, gestational diabetes, prediabetes, or insulin resistance, understanding this connection is not about panic. It is about planning. Good glucose management, vaccination decisions, early testing, timely treatment, and a practical sick-day plan can dramatically reduce the drama. Your pancreas may already have enough emails to answer; it does not need COVID-19 forwarding more chaos.
What Does “Risk” Mean in Diabetes and COVID-19?
When people ask whether diabetes increases COVID-19 risk, they usually mean one of three things:
- Does diabetes make infection more likely?
- Does diabetes make severe COVID-19 more likely?
- Can COVID-19 infection increase the risk of diabetes later?
These are related questions, but the answers are not identical. Current medical understanding suggests that diabetes itself is not clearly proven to increase the chance of being exposed to or infected by SARS-CoV-2, the virus that causes COVID-19. Exposure still depends heavily on ventilation, close contact, masking, vaccination status, crowding, and whether someone nearby is carrying the virus.
The bigger concern is what happens after infection. People with diabetes are more likely to experience serious complications from COVID-19, especially when blood glucose is not well managed or when diabetes is accompanied by obesity, chronic kidney disease, heart disease, high blood pressure, older age, or immune system problems.
Why COVID-19 Can Be More Serious for People With Diabetes
COVID-19 is not just “a cold with a public relations team.” It can trigger inflammation throughout the body, stress the lungs and blood vessels, affect clotting, and disrupt normal metabolism. Diabetes already involves problems with glucose regulation, insulin action, inflammation, and sometimes blood vessel health. Put those together, and the body may have a harder time staying balanced during infection.
High Blood Sugar Can Weaken Immune Response
When blood sugar remains above target, immune cells may not respond as efficiently. That does not mean the immune system stops working; it means it may be less coordinated. Think of it as a fire department arriving at the right house but spending five minutes debating where the hose is. During a viral infection, those minutes matter.
Above-target glucose can also increase inflammation. COVID-19 can increase inflammation too. The combination may raise the risk of complications such as dehydration, severe fatigue, breathing problems, hospitalization, or slower recovery.
Illness Hormones Raise Glucose Levels
When the body is sick, it releases stress hormones such as cortisol and adrenaline. These hormones help the body respond to infection, but they also tell the liver to release more glucose. For someone with diabetes, this can push blood sugar higher than usual, even if they are eating less than normal.
This is why some people notice that their glucose numbers climb during COVID-19 even when their appetite disappears. It can feel unfair, like getting a parking ticket while your car is in the shop, but it is a common sick-day pattern.
Dehydration Can Make Everything Worse
Fever, sweating, diarrhea, vomiting, and reduced fluid intake can all contribute to dehydration. Dehydration can concentrate glucose in the blood and make it harder for the kidneys to remove excess sugar. For people taking certain diabetes medications, dehydration may also raise the risk of side effects.
Anyone with diabetes who becomes ill should pay close attention to fluid intake, glucose levels, symptoms, and medication instructions from their healthcare team.
Type 1 Diabetes, Type 2 Diabetes, and COVID-19: Is the Risk Different?
Both type 1 and type 2 diabetes can increase the risk of severe COVID-19 outcomes, but the reasons may differ. Type 1 diabetes is an autoimmune condition in which the body produces little or no insulin. During infection, people with type 1 diabetes are especially vulnerable to diabetic ketoacidosis, or DKA, if insulin needs rise and the body begins breaking down fat too quickly.
Type 2 diabetes often occurs alongside other risk factors, including obesity, high blood pressure, fatty liver disease, chronic kidney disease, and cardiovascular disease. These conditions can add up. COVID-19 does not politely choose one organ system and stay there; it may stress multiple systems at once.
The practical takeaway is simple: the type of diabetes matters, but overall health, glucose management, age, medications, vaccination status, and other medical conditions matter too. A well-managed person with diabetes may have a lower risk than someone with uncontrolled blood sugar and multiple complications.
Can COVID-19 Trigger New Diabetes?
Research has found an association between COVID-19 infection and new diagnoses of diabetes after infection. This does not mean every COVID-19 infection causes diabetes. It also does not mean someone who gets COVID-19 should immediately blame the virus for every future glucose reading. Science is more careful than that, even when headlines are wearing tap shoes.
Several possible explanations are being studied:
- COVID-19 may increase inflammation and stress hormones that reveal diabetes in someone who was already at risk.
- The infection may temporarily worsen insulin resistance.
- Severe illness, hospitalization, steroid treatment, reduced activity, and weight changes may affect glucose levels.
- The virus may have effects on pancreatic beta cells or metabolic pathways, although this remains an area of ongoing research.
In many cases, COVID-19 may act like a “stress test” for metabolism. A person with prediabetes or insulin resistance might not know anything is wrong until a major illness pushes blood sugar high enough to be noticed. The virus may not be the only cause, but it can be the loud alarm that reveals the problem.
COVID-19 and Prediabetes: A Quiet Risk Worth Taking Seriously
Prediabetes means blood sugar is higher than normal but not yet in the diabetes range. It is common, often silent, and easy to ignore because it rarely sends a dramatic text message saying, “Hello, I am insulin resistance.”
COVID-19 may be harder on people with metabolic risk factors, even before a formal diabetes diagnosis. People with prediabetes, abdominal weight gain, high triglycerides, high blood pressure, or a family history of type 2 diabetes should consider asking their healthcare provider about A1C testing after recovery, especially if they experience unusual thirst, frequent urination, blurry vision, unexpected weight loss, fatigue, or slow-healing infections.
Symptoms That Need Extra Attention
People with diabetes should watch both COVID-19 symptoms and diabetes-related warning signs. COVID-19 symptoms may include fever, cough, sore throat, congestion, body aches, headache, fatigue, shortness of breath, nausea, diarrhea, or loss of taste or smell. Symptoms vary by variant, immune status, and vaccination history.
Call a Healthcare Provider Promptly If You Have:
- COVID-19 symptoms and diabetes, especially if you are older or have other medical conditions
- Persistent high blood sugar despite following your sick-day plan
- Moderate or large ketones
- Vomiting or inability to keep fluids down
- Shortness of breath, chest pain, confusion, bluish lips, or severe weakness
- Signs of dehydration, such as dizziness, very dark urine, or dry mouth
For people at higher risk of severe illness, early COVID-19 treatment may be available. Antiviral treatment works best when started soon after symptoms begin, so waiting “just to see what happens” can close the treatment window. COVID-19 loves procrastination; your treatment plan should not.
How COVID-19 Can Disrupt Blood Sugar
During COVID-19, blood sugar can rise, fall, or swing around like it drank too much coffee. Several factors can affect glucose:
- Fever and inflammation: may raise glucose.
- Reduced appetite: may lower glucose, especially if medications continue unchanged.
- Dehydration: may raise glucose and increase ketone risk.
- Less activity: may increase insulin resistance.
- Sleep disruption: may worsen glucose control.
- Steroid medications: may significantly raise blood sugar.
This is why a diabetes sick-day plan is essential. The plan should explain how often to check glucose, when to check ketones, how to adjust medications if instructed, how much fluid to drink, when to call the clinic, and when to seek emergency care.
Diabetic Ketoacidosis and COVID-19
Diabetic ketoacidosis, or DKA, is a serious complication that happens when the body does not have enough insulin and begins producing high levels of ketones. It is more common in type 1 diabetes but can also occur in type 2 diabetes, particularly during severe illness or with certain medications.
COVID-19 can increase DKA risk because illness raises insulin needs, reduces appetite, causes dehydration, and may make normal diabetes routines harder to follow. Warning signs include nausea, vomiting, abdominal pain, fruity-smelling breath, rapid breathing, confusion, extreme thirst, frequent urination, and very high blood sugar. Some people, especially those using SGLT2 inhibitors, may develop ketoacidosis even when glucose is not extremely high.
Anyone with diabetes should ask their healthcare provider when to test ketones and what ketone results require urgent care.
Long COVID and Diabetes
Long COVID refers to symptoms or health problems that continue or appear after the initial infection, often lasting months. Symptoms may include fatigue, brain fog, shortness of breath, dizziness, sleep problems, palpitations, digestive issues, mood changes, or exercise intolerance.
People with underlying health conditions, including diabetes, may have a higher risk of complicated recovery. Severe initial COVID-19 illness, hospitalization, repeated infections, and being unvaccinated may also increase long COVID risk. For someone with diabetes, long COVID can make glucose management harder because fatigue, poor sleep, reduced exercise tolerance, appetite changes, and stress all affect blood sugar.
Recovery may require patience and teamwork. Primary care providers, endocrinologists, diabetes educators, cardiologists, pulmonologists, physical therapists, and mental health professionals may all play a role. That sounds like a lot of people, but chronic symptoms sometimes need a bigger group chat.
Prevention: How People With Diabetes Can Lower Risk
Prevention is not about living in a bubble. Bubbles are bad housing and worse long-term strategy. The goal is layered protection.
1. Stay Current on Vaccination Decisions
COVID-19 vaccines help reduce the risk of severe illness, hospitalization, and death. People with diabetes should talk with a healthcare provider about current vaccine recommendations, timing after recent infection, and whether additional risk factors make vaccination especially important.
2. Improve Glucose Management Before Illness Happens
Better glucose control before infection can reduce complications if illness occurs. This does not mean every number must be perfect. It means having realistic targets, taking medications as prescribed, checking glucose as recommended, and following up when readings drift out of range.
3. Keep a Sick-Day Kit
A useful sick-day kit may include a thermometer, glucose meter supplies or continuous glucose monitor supplies, ketone strips or a blood ketone meter if recommended, electrolyte fluids, easy-to-digest carbohydrates, medication list, insurance information, and phone numbers for the diabetes care team.
4. Test Early and Ask About Treatment
If COVID-19 symptoms appear, testing early can help guide next steps. People at higher risk should contact a healthcare provider quickly to ask whether antiviral treatment is appropriate. Some treatments interact with common medications, so a medication review matters.
5. Use Clean Air and Common Sense
Good ventilation, staying home when sick, masking in crowded indoor spaces during surges, hand hygiene, and avoiding close contact with visibly ill people can reduce exposure. These steps are not glamorous, but neither is coughing into a glucose log.
What to Do If You Have Diabetes and Test Positive for COVID-19
First, do not panic. Panic is terrible at math and even worse at medication dosing. Instead, follow a clear plan:
- Contact your healthcare provider, especially if you are older, pregnant, immunocompromised, or have kidney, heart, or lung disease.
- Ask whether COVID-19 antiviral treatment is appropriate.
- Check glucose more often than usual.
- Continue insulin unless your healthcare provider gives different instructions.
- Drink fluids regularly.
- Eat small amounts of carbohydrates if you cannot tolerate normal meals.
- Check ketones according to your sick-day plan.
- Seek urgent care for severe symptoms, breathing difficulty, dehydration, confusion, or concerning ketone results.
People using insulin should never stop insulin simply because they are eating less. Illness can raise insulin needs even when food intake drops. Medication adjustments should be guided by a clinician or a previously prepared sick-day plan.
Should You Check for Diabetes After COVID-19?
Not everyone needs special testing after every mild infection. However, checking blood sugar or A1C after COVID-19 may be wise for people who have risk factors for diabetes or symptoms of high blood sugar.
Consider discussing screening with a healthcare provider if you have:
- Prediabetes or a history of gestational diabetes
- Obesity or abdominal weight gain
- Family history of type 2 diabetes
- High blood pressure or abnormal cholesterol
- Polycystic ovary syndrome
- Unusual thirst, frequent urination, blurry vision, fatigue, or unexplained weight loss after COVID-19
An A1C test, fasting glucose, or other tests may help determine whether glucose changes are temporary or part of a longer-term pattern.
Common Myths About Diabetes and COVID-19
Myth 1: “If I have diabetes, I will definitely get severe COVID-19.”
False. Diabetes increases risk, but it does not guarantee a bad outcome. Many people with diabetes recover from COVID-19 without hospitalization, especially when their diabetes is well managed and they receive timely care.
Myth 2: “Only type 2 diabetes matters.”
False. Both type 1 and type 2 diabetes can matter. Type 1 diabetes carries special concern for DKA, while type 2 diabetes often overlaps with cardiovascular, kidney, and weight-related risk factors.
Myth 3: “COVID-19 always causes diabetes.”
False. COVID-19 has been linked with newly diagnosed diabetes in some studies, but the relationship is complex. Infection may trigger, reveal, or accelerate diabetes in people who were already vulnerable.
Myth 4: “If I feel better after a few days, I do not need to watch my glucose.”
Not so fast. Blood sugar may remain unstable during recovery. Keep monitoring until eating, hydration, activity, and glucose patterns return to normal.
Experiences and Practical Scenarios: What This Looks Like in Real Life
Real-life diabetes and COVID-19 management rarely looks like a perfect brochure. It looks more like a kitchen counter covered with tissues, test strips, water bottles, a thermometer, and someone asking, “Did I already take my medicine?” three times in one hour. That is normal. The goal is not perfection; the goal is safe, steady decisions.
Consider a person with type 2 diabetes who usually has decent glucose numbers but gets COVID-19 and spends three days on the couch. They eat soup, crackers, and orange juice because nothing else sounds good. Their usual walking routine disappears. Sleep becomes choppy. Suddenly, their glucose readings are 60 to 100 points higher than usual. This does not mean they “failed.” It means illness changed the rules. The best response is to hydrate, monitor, contact the care team if numbers stay high, and ask whether medication adjustments or COVID-19 treatment are needed.
Now picture someone with type 1 diabetes using an insulin pump. They develop fever and body aches, then notice glucose climbing even though they barely eat. Their correction dose works for two hours, then glucose rises again. This is a classic time to check ketones. If ketones are moderate or large, or if vomiting begins, urgent medical guidance is needed. DKA can develop quickly, and waiting overnight to “see if it settles” can be risky. The pump, the sensor, and the person are all doing their best, but infection may demand a stronger plan.
Another common experience happens after recovery. A person who never had diabetes gets COVID-19, recovers, and weeks later notices intense thirst, frequent urination, and blurry vision. They assume it is lingering fatigue or too much screen time. Testing reveals high blood sugar. In this situation, COVID-19 may have uncovered an existing risk. Maybe prediabetes was already present. Maybe inflammation and inactivity pushed glucose higher. Either way, symptoms deserve attention. Early diagnosis can prevent complications and make treatment easier.
There is also the emotional side. People with diabetes may feel extra anxiety when COVID-19 is spreading at work, school, or family gatherings. That concern is understandable, but it should become preparation rather than fear. A practical plan helps: know where tests are, keep medications refilled, write down sick-day instructions, ask about vaccines, and decide when to call the doctor. Planning does not make someone fragile. It makes them organized. And organized is powerful, even if the supply drawer still contains seven mystery lancets from 2018.
Caregivers also need support. A parent managing a child’s diabetes during COVID-19 may be checking glucose overnight, encouraging fluids, calculating carbohydrates, and watching for ketones while also being sick themselves. A spouse caring for an older adult with diabetes may need to track oxygen levels, medications, meals, and warning signs. In these moments, written instructions are better than memory. Illness makes everyone’s brain run like a browser with 47 tabs open.
The most helpful experience-based lesson is this: small actions taken early often prevent big problems later. Testing early, calling the clinic early, drinking fluids early, checking ketones early, and treating high-risk COVID-19 early can change the outcome. Diabetes management during COVID-19 is not about being dramatic. It is about noticing patterns before they become emergencies.
Conclusion: So, Does Infection Increase Risk?
Diabetes and COVID-19 have a two-way relationship. Diabetes does not necessarily mean a person is more likely to catch COVID-19, but it can increase the risk of severe illness, especially when glucose is poorly controlled or other health conditions are present. COVID-19 infection, meanwhile, can disrupt blood sugar and may be associated with a higher risk of new-onset diabetes in some people.
The good news is that risk is not destiny. Vaccination discussions, glucose management, early testing, timely treatment, sick-day planning, hydration, ketone monitoring, and follow-up care can all help. Diabetes may make COVID-19 more complicated, but with the right plan, it does not get to run the whole show.
Note: This article is for educational purposes only and does not replace medical advice. People with diabetes should follow a personalized care plan from their healthcare provider, especially during COVID-19 infection or recovery.
