Yes, people with diabetes can donate blood if their blood sugar levels are well-controlled and they feel healthy on donation day. Both type 1 and type 2 diabetes are eligible conditions, along with prediabetes, as long as your glucose levels stay within a safe range most of the time. Every two seconds, someone in the United States needs donated blood, and people with diabetes can be part of the solution .

What Does "Well-Controlled" Diabetes Actually Mean?

When doctors and blood banks say your diabetes must be "well-controlled," they mean your blood glucose is staying within a safe and normal range most of the time. You are taking your medicine regularly, eating right, and not having dangerous highs or lows very often. You do not need perfect numbers. However, if your A1C (a measure of average blood sugar over three months) is well above 9%, or your blood sugar level is over 200 mg/dL on donation day, it is smarter to wait a bit. Not because the rules say you have to, but because your blood quality might be lower during that time .

According to the American Red Cross, donors with diabetes are eligible as long as they feel well and their condition is managed. The key question is always: how are your blood glucose levels right now?

Which Diabetes Medications Are Safe for Blood Donation?

Good news for most people managing diabetes: most diabetes medications do not stop you from donating. Whether you are on insulin injections like Apidra or Humalog, or injectable drugs like Ozempic or Mounjaro, you are still generally eligible. Oral medications like metformin are also fine. GLP-1 medications like Ozempic and Zepbound are not listed as disqualifying by the American Red Cross. As long as your diabetes is well controlled, you are good to go .

There is one important exception: if you have ever used bovine insulin (insulin made from cattle in the United Kingdom) since 1980, you are not eligible to donate. This is because of concerns about a rare condition called variant Creutzfeldt-Jakob Disease. However, this type of insulin is not used anymore, so most people do not need to worry about it .

There is one medication that does make you ineligible: Warfarin, a blood thinner that can interact with certain diabetes drugs and cause serious blood sugar drops. If you take Warfarin, you cannot donate. You should never stop taking a prescribed medicine just to become eligible to donate, as that would put your health at serious risk. Talk to your doctor if you have questions about your specific medications .

Tips for Preparing to Donate Blood With Diabetes

• Hydration: Drink a lot of water in the days before your appointment. This helps with the donation and keeps you from feeling dizzy.
• Iron intake: Eat iron-rich foods like spinach, red meat, or beans one to two weeks before donating to support red blood cell production.
• Sleep: Get a good night's sleep the night before. Eight or more hours is ideal for your body to be in optimal condition.
• Pre-donation meal: Eat a balanced meal before you go. Skipping meals when you have diabetes can cause your blood glucose to drop dangerously.
• Documentation: Bring your list of current medications with you and a valid ID.
• Blood sugar check: Monitor your blood sugar level before you leave the house. If it is within your normal range, you are likely good to go. If it is too high or too low, contact your doctor before heading in.

What Happens to Your Blood Sugar After Donating?

After donating, your body starts working to replace the red blood cells it just lost. For people with diabetes, this process can cause a few things worth knowing about. Some type 1 diabetics report slightly higher blood glucose in the three to five days after donating. This is temporary .

Here is something a lot of people do not know: donating blood can make your A1C look lower than it really is. This is not dangerous, but it can be confusing if you get an A1C test within a few months of donating. When you donate, your body makes new red blood cells faster than normal. These new cells do not yet carry much glucose, so your HbA1c reading can drop. It does not reflect your real long-term blood sugar control. According to research by the American Diabetes Association, this false lowering of A1C can last up to two months after donation .

Always tell your doctor if you have recently donated blood before getting an A1C test. After donating, make sure to rest, drink plenty of fluids, and eat well. Monitor your blood sugar closely for a few days. If anything feels off, call your doctor .

Are There Other Types of Blood Donation You Can Make?

Yes. People with diabetes can also donate plasma, which is the liquid part of your blood. It carries nutrients, proteins, and important compounds throughout your body. The rules for plasma donation are similar to whole blood donation. Your diabetes must be stable and well-managed, you should be in good general health, and you should be hydrated and fed well on donation day. Unlike blood, which cannot be manufactured, plasma can be collected and stored to help people with burns, shock, and other serious conditions .

Platelet donation is another option. Platelets are tiny blood cells that help your body form clots and stop bleeding. People going through cancer treatment or major surgeries often need platelet transfusions. If your diabetes is well controlled, you can donate platelets every 7 days. That is actually more often than whole blood, which can only be given every 56 days. So if you are eager to help more often, platelet donation might be a good fit for you .

When Should You Hold Off on Donating?

There are some situations where you should hold off, even if you have well-managed diabetes. Do not donate if your blood glucose is too high or too low on that day. Do not donate if you have an active infection, fever, or feel sick. Do not donate if you are pregnant. Do not donate if you recently had a blood transfusion or organ transplant in the last three months. Do not donate if you have recently traveled to a malaria-risk area .

The bottom line is this: if you are not feeling your best, it is perfectly okay to reschedule. Your health comes first. Every donor also needs to meet some basic eligibility rules that apply to everyone, including people managing diabetes. You must be at least 17 years old (16 in some states with parental consent), weigh at least 110 pounds, be in good health and feeling well on the day of your donation, and bring a valid ID with you .

If you have diabetes, you also need to share that during the screening process. The staff will ask about your condition, your medications, and how well managed your blood sugar is. Be honest. They are not there to judge you. They just want to keep both you and the person receiving the blood safe .