Can You Donate Blood If You Have Diabetes?
You’ve already been through a lot managing your diabetes. The finger pricks, the routines, the constant awareness—it’s a full-time job. So when the thought of donating blood crosses your mind, it’s natural to wonder: Can I actually do this? Will it be safe? Will they even let me?
You’re not alone in asking those questions. So many people living with type 1 or type 2 diabetes feel the same way. And here’s the encouraging truth: yes, you often can donate blood—if your condition is well managed.
Donating blood is one of the simplest, most powerful ways to help others. It’s used in emergencies, surgeries, cancer treatments, and more. But for those of us managing a chronic condition, the decision to give isn’t always straightforward.
That’s why this guide exists—to walk you through it all. From what to expect and how to prepare, to how to feel good (and safe) afterward. Because if you’re ready to help save lives, we’re here to make sure you can do it with confidence—and care.
Who can donate blood in general?
Before we dive into diabetes specifically, it helps to understand the general criteria for blood donation in most countries (such as the United States, Canada, and the UK):
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Be at least 17 years old (16 with parental consent in some areas)
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Weigh at least 110 pounds (50 kg)
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Be in good general health on the day of donation
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Not have donated in the past 8 weeks (for whole blood)
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Pass a hemoglobin (iron) screening
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Not be currently sick with fever, infection, or illness
Organizations like the FDA, American Red Cross, NHS Blood and Transplant, and Canadian Blood Services all have similar guidelines.
Can you donate blood if you have diabetes?
Yes, people with diabetes can often donate blood—if their blood sugar is well-controlled and they meet general health criteria.
According to the U.S. Food and Drug Administration (FDA) and the National Institutes of Health (NIH), diabetes itself is not a disqualifier. The key is that blood sugar levels must be within a safe and stable range, managed either with insulin or oral medications.
In the U.S., both type 1 and type 2 diabetics may be eligible to donate blood if:
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They feel well on donation day
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Their diabetes is controlled
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They meet standard eligibility like weight and age
In the UK, donation rules are more restrictive. For instance, the NHS does not allow people on insulin to donate, even if their diabetes is well-managed. Always check your local donation agency’s rules.
Can insulin use or diabetes medications disqualify you?
In most cases, diabetes medications—including metformin and insulin—don’t disqualify you from donating blood in the U.S. The American Red Cross allows people on insulin to donate, provided they’re healthy otherwise.
However, a specific type of insulin made from beef (bovine insulin) disqualifies people due to past risks associated with Creutzfeldt-Jakob disease. This form of insulin was discontinued in 1998, so it’s rarely an issue today.
Still, bring a list of your current medications when donating blood. It helps screeners ensure everything is safe.
For more information on insulin use, read our guide on when is the best time to take insulin for type 2 diabetes.
What about your type of diabetes?
Both type 1 and type 2 diabetes are acceptable for donation—as long as your condition is well-managed.
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Type 1 diabetes: Your body produces little or no insulin. As long as your insulin therapy is consistent and your blood sugar is in a safe range, you may donate.
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Type 2 diabetes: Your body resists insulin or doesn’t use it well. With oral meds or lifestyle management, you may be eligible.
The type of diabetes matters less than how well it’s controlled. Blood centers care most about current health, glucose levels, and any complications.
If you're navigating type 2 or age-related insulin resistance, explore more in our post on type 4 diabetes.
What are the risks of donating blood with diabetes?
Most people with diabetes can donate blood safely, but it’s important to prepare and be aware of possible side effects:
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Low blood sugar (hypoglycemia): Can occur if you skip meals or take insulin without adjusting timing.
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Dizziness or fatigue: Blood loss may cause lightheadedness, especially if you’re dehydrated.
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Blood sugar fluctuations: The body’s stress response to blood donation might affect your glucose levels short term.
Always check your blood sugar before and after donation and speak to your doctor if unsure.
You can also read about blood sugar test kits to stay better prepared.
How to prepare for blood donation with diabetes
Here are some blood donation preparation tips:
1. Talk to your doctor
Make sure your doctor agrees that you’re stable enough to donate.
2. Eat a balanced meal
Have a protein- and fiber-rich meal 1–2 hours before donating. Avoid high-sugar snacks.
3. Hydrate properly
Drink water before and after donation to prevent dizziness.
4. Bring supplies
Pack glucose tablets, a small snack, your glucose meter, and any needed meds.
5. Monitor your blood sugar
Test before and after. Know your trends.
6. Rest afterward
Skip strenuous activities post-donation. Allow your body to recover.
What happens during the donation process?
The donation experience is mostly the same whether or not you have diabetes:
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Registration: Provide ID and fill out health forms.
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Pre-donation screening: Includes a questionnaire, hemoglobin check, and brief physical.
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Donation: About one pint (unit) of blood is drawn. This takes around 8–10 minutes.
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Recovery: You’ll rest 10–15 minutes with snacks and water. People with diabetes may prefer to bring their own suitable snacks.
If you’re donating other components like plasma or platelets, the process may take longer but follows a similar setup.
If you're using insulin or oral medications, be aware that glucose in urine can be a signal of poor control and may warrant postponing donation.
What should you do after donating blood?
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Monitor your blood sugar closely for the next 24 hours
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Eat iron-rich foods to replenish nutrients (spinach, lean meats, beans)
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Drink fluids to stay hydrated
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Avoid alcohol and heavy exercise for the rest of the day
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Track your recovery and contact your healthcare provider if you feel unwell
Stay hydrated and monitor your recovery. If you experience ongoing fatigue or changes in urination, it might be worth checking for protein in urine or creatinine levels.
How often can people with diabetes donate blood?
Generally, donors must wait at least 56 days (8 weeks) between whole blood donations. However, for people with diabetes, some doctors recommend waiting up to 4 months to allow hemoglobin A1c to stabilize.
A 2017 study found that blood donation may impact A1c readings for up to 2 months. So, if you're monitoring A1c closely, be aware that donation might slightly skew results.
Some experts suggest waiting longer between donations to avoid misleading test results like A1c fluctuations or elevated urine glucose levels.
Are there reasons you might be turned away?
Yes. Blood centers may defer you if:
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Your blood sugar is too high or too low that day
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You feel unwell or have flu-like symptoms
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You’ve recently changed diabetes medications
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You have complications like kidney disease or neuropathy
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You previously used beef insulin
It’s always okay to postpone your donation until you’re feeling your best. Honesty during the screening helps ensure safety for both you and recipients.
Can donating blood help diabetes?
While blood donation isn’t a treatment for diabetes, some research suggests potential metabolic benefits:
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A 2016 study showed improved glucose tolerance in men 3 weeks after donation
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Lowering iron stores may reduce oxidative stress linked to type 2 diabetes
Still, the purpose of donating blood should be to help others, not to treat a medical condition. Talk to your provider before drawing conclusions.
Can people with diabetes donate plasma?
Yes—in many cases, people with diabetes can donate plasma or platelets if their condition is well-controlled.
However, policies vary by facility. Call ahead to ensure your medications, health history, and recent blood sugar levels won’t be an issue.
Yes, you can donate if you're stable
People with diabetes can donate blood if their condition is well-managed. You’ll need to be feeling well, have blood sugar in an acceptable range, and meet other general health guidelines.
Prepare ahead of time by eating a balanced meal, staying hydrated, and bringing your monitoring tools. Check your blood sugar before and after the procedure and follow your care plan.
With the right approach, donating blood can be a safe and generous way to give back—without putting your health at risk.
Related Resources
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How to Reverse Kidney Damage from Diabetes
Explore strategies to protect and potentially restore kidney function if you're living with diabetes. -
Blood Sugar Monitoring in Diabetes: Start Checking Your Blood Glucose
A practical guide to daily monitoring, helping you manage levels safely—especially before and after donating blood. -
Urine Glucose Levels Chart: Understanding Results
Learn what your urine glucose levels indicate and how they relate to your diabetes management plan.
References
Anwar Borai, Livingstone, C., Anwar Farzal, Dalal Baljoon, Abeer Al Sofyani, Suhad Bahijri, … Ferns, G. (2015). Changes in metabolic indices in response to whole blood donation in male subjects with normal glucose tolerance. Clinical Biochemistry, 49(1-2), 51–56. https://doi.org/10.1016/j.clinbiochem.2015.08.023
CDC. (2024, June 5). Manage Blood Sugar. Retrieved July 13, 2025, from Diabetes website: https://www.cdc.gov/diabetes/treatment/index.html
Diabetes and Blood Donation. (2025). Retrieved July 13, 2025, from Redcrossblood.org website: https://www.redcrossblood.org/donate-blood/dlp/health-assessment/diabetes.html
Donation Process Overview. (2025). Retrieved July 13, 2025, from Redcrossblood.org website: https://www.redcrossblood.org/donate-blood/blood-donation-process/donation-process-overview.html
General donor assessment. (2025). Retrieved July 13, 2025, from Nih.gov website: https://www.ncbi.nlm.nih.gov/books/NBK138219/
Kundu, D., Roy, A., Mandal, T., Bandyopadhyay, U., Ghosh, E., & Ray, D. (2013). Relation of iron stores to oxidative stress in type 2 diabetes. Nigerian Journal of Clinical Practice, 16(1), 100–100. https://doi.org/10.4103/1119-3077.106776
Office. (2025). FDA ensures the safety of millions of units of blood donated each year. Retrieved July 13, 2025, from U.S. Food and Drug Administration website: https://www.fda.gov/consumers/consumer-updates/have-you-given-blood-lately
Who can give blood. (2018). Retrieved July 13, 2025, from Who.int website: https://www.who.int/campaigns/world-blood-donor-day/2018/who-can-give-blood
