Save lives and empower your health! For a limited time in March, the Red Cross will perform free A1C testing with successful blood, platelet, and plasma donations. Make an appointment now »
Understanding Diabetes as a Blood Donor
Being informed about our health is key to preventing chronic illness and saving lives. The American Red Cross is committed to providing valuable information on topics that will help maintain the health of people across the country. By raising awareness and sharing knowledge, we can work together to ensure communities remain strong and healthy for years to come.
To help our donors maintain their well-being, the Red Cross will expand its health offerings to include A1C testing, commonly used to screen for prediabetes and diabetes, to all donors who successfully give blood, platelets or plasma March 1-31, 2025. Test results will be available in one to two weeks through the Red Cross Blood Donor App or a donor’s account at RedCrossBlood.org.
With more than 38 million people in the U.S. living with diabetes, and about 90% of cases being Type 2 diabetes, awareness and early detection are crucial. However, many people with prediabetes or early-stage Type 2 diabetes rarely have symptoms until the condition has advanced to the point of organ damage. This may explain why 8.7 million people in the U.S. have undiagnosed diabetes, and the majority of those with prediabetes are unaware of their condition.
What is Diabetes?
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Diabetes is a condition that prevents the body from effectively turning food into energy. For an individual with diabetes, the body either struggles to produce insulin – a hormone produced in the pancreas that helps convert sugar into energy – or cannot use insulin properly, leading to elevated blood glucose (blood sugar) levels.
There are two main types of diabetes – Type 1 and Type 2 diabetes – along with a precursor condition called prediabetes.
Type 1 diabetes is an autoimmune disease that often develops early in life. In Type 1 diabetes, a person’s immune system attacks the insulin-producing cells in the pancreas. Without enough insulin, sugar stays in the bloodstream, leading to dangerously high blood sugar levels. Type 1 diabetes cannot be prevented, but it can be treated effectively, such as with insulin therapy to manage blood sugar levels.
Type 2 diabetes is the most common type of diabetes. For individuals with Type 2 diabetes, the body becomes resistant to insulin and doesn't use it effectively. The pancreas tries to make more insulin to keep blood sugar levels normal but can’t keep up, causing blood sugar levels to rise to dangerous levels. Type 2 diabetes develops slowly, often without early symptoms. It is preventable and often reversible and can be managed through lifestyle changes, insulin injections and/or medication.
Prediabetes is a serious health condition where blood sugar levels are higher than normal but not high enough for a diabetes diagnosis. People with prediabetes have a condition called insulin resistance. This occurs when your body's cells don't respond properly to insulin. Prediabetes typically has no symptoms and is very common in the U.S., with approximately a third of all Americans affected. Insulin resistance – and prediabetes – is often reversible through lifestyle changes and/or medications
Diabetes and Blood Donation
People with prediabetes and diabetes are generally eligible to donate blood, platelets and plasma if they are feeling well and their diabetes is well managed.
Can I donate blood if I have diabetes or insulin resistance that is managed with insulin or other medications?
In most situations, the type of medication you take to manage your diabetes or insulin resistance won't disqualify you from donating blood. Whether you take insulin injections like Apidra or Humalog, an injected diabetes medication like Ozempic or Mounjaro, or oral medications like metformin, you are still eligible to donate if your diabetes or insulin resistance is currently under control.
Prepare for a donation by:
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Those with diabetes should be sure to monitor their blood sugar levels after donating and rest as needed.
Learn more about what to do before, during and after your donation.
Recognize Your Risks
Genetics play a significant role in the development of Type 1 and Type 2 diabetes. Individuals who are over 45 years old, are overweight or obese, have experienced gestational diabetes during pregnancy or have high blood pressure are also at a higher risk of developing prediabetes and Type 2 diabetes.
Unfortunately, African or Black, Hispanic, Latino and Asian Americans, as well as American Indians, all have higher rates of diabetes and serious diabetes-related health complications, including death, compared to non-Hispanic white Americans. Even though more people in these communities have diabetes, accessing health care is a serious challenge due to high costs, insurance coverage gaps and geographic disparities, particularly in rural and diverse communities. Primary care shortages also worsen these issues, leading to longer wait times and delayed treatments.
Potential Health Complications
Prediabetes and diabetes can lead to serious health complications if not managed properly. In the early stages of prediabetes or Type 2 diabetes, individuals may experience lightheadedness, tiredness, increased appetite or thirst and frequent urination. However, most people in the early stages have no symptoms, which is why routine screening is so important.
Ongoing high blood sugar levels can damage blood vessels, leading to inflammation and plaque buildup, which affects several key organs:
- Eyes: Damage to the retina can lead to blurry vision, cataracts or glaucoma.
- Kidneys: Most people experience few obvious symptoms of kidney disease until kidney function becomes very poor, potentially leading to the need for dialysis to remove harmful toxins.
- Nerves: Nerve damage can cause numbness in the hands and feet, increasing the risk of injury, and may also cause sexual dysfunction.
- Skin: Poor blood flow caused by diabetes can result in slow healing of cuts and an increased risk of ulcers, especially on the feet.
- Heart: Increased risk of heart attack.
- Brain: Increased risk of stroke.
Diabetes also weakens the immune system, making infections more likely.
Know Your Numbers
There are three standard tests medical professionals use to diagnose prediabetes and diabetes:
- Fasting plasma glucose (FPG) test: A blood test that screens for diabetes by measuring blood sugar after fasting for at least 8 hours.
- Oral glucose tolerance test (OGTT): A blood test that measures blood sugar two to three hours after drinking a sugar solution.
- Hemoglobin A1C (A1C) test: A blood test that measures average blood sugar over the past three months. No fasting is needed.
The A1C test is one of the most common blood tests used to diagnose diabetes and monitor blood sugar levels. It measures the percentage of hemoglobin in red blood cells bound to glucose. A high A1C level may indicate prediabetes or diabetes. This test does not require fasting and provides an average blood sugar level over the past three months.
Once diagnosed, individuals may be prescribed medications, daily insulin or other health interventions to manage their blood sugar levels.
How to Read A1C Levels Test Results:
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This A1C table image above provides information about A1C levels and their corresponding diagnostic categories. It includes three rows:
- Normal: A1C level is less than 5.7%.
- Prediabetes: A1C level ranges from 5.7% to 6.4%.
- Diabetes: A1C level is 6.5% or higher.
Diabetes Prevention
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Many health experts believe that prediabetes and Type 2 diabetes are largely preventable through lifestyle changes. According to the Centers for Disease Control and Prevention, healthy lifestyle changes can reduce the risk of Type 2 diabetes by half. Here’s how:
- Healthy diet: Eat a well-balanced diet that includes vegetables, whole grains and lean proteins and drink plenty of water.
- Regular exercise: Engage in regular physical activity, aiming for at least 150 minutes of moderate-intensity aerobic exercise each week.
- Maintain a healthy weight: Aim for a healthy body weight. If you have excess weight, losing even a small amount can reduce your risk.
- Avoid tobacco and alcohol: Avoid or limit these substances.