Can you donate blood if you have diabetes

Recent research suggests giving blood may temporarily improve insulin production and glucose tolerance.

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Donating blood lowers the body’s iron stores, with potential health benefits.© PHOTODISC / GETTY IMAGES

Heart attack, stroke and type II diabetes have all been shown to be less common in individuals that regularly donate blood. But, according to a new study led by researchers at King Abdullah International Medical Research Center (KAIMRC), just a single blood donation can temporarily improve a person’s insulin production and glucose tolerance.

KAIMRC pathologist Anwar Borai led an international team that tested the levels of several key diabetes-related biomarkers in the blood of 42 healthy male donors.

Biomarkers, including those related to glycaemic status (the level of glucose in the donor’s blood), insulin production and iron levels, were tested before donation and then one day, one week, three weeks and three months after giving blood.The results show that regular, repeated blood donation is not required to see a beneficial effect on the donor’s glucose tolerance. “The glycaemic status of the donor can be mproved even after a single blood donation,” Borai says.

The improvement was particularly evident three weeks after donation. By three months, most of the tested biomarkers returned to their pre-donation levels. Borai says improvements could continue if donors made healthy lifestyle changes after donation.

The team suspects that the improvement in glucose tolerance is linked to the levels of iron and other metals in the bloodstream. “It is well known that low iron stores may contribute to enhanced insulin sensitivity,” Borai says. Iron-containing compounds in the blood can produce damaging molecules, known as reactive oxygen species, which have been shown to interfere with insulin signalling, lowering a person’s tolerance of glucose. As Borai’s results confirm, giving blood removes some iron from the body, perhaps helping restore insulin signalling.

The team next plans to repeat the study with people who have impaired glucose tolerance and full-blown type II diabetes. “Blood donation could be an alternative way to improve glycaemic status, particularly in people with impaired glucose tolerance who are on a diet and have not started their treatment yet,” says Borai.

The technique may also be used to assess how blood donation affects other areas of health, including levels of white blood cells called lymphocytes, which form part of the immune system. “I am preparing the second part of the study which is about changes in lymphocyte subsets and general immunity after whole blood donation,” Borai says.

November is American Diabetes Month. Millions of people around the world live with diabetes or know someone living with diabetes. A common misconception is that being a diabetic means you can’t donate blood, but that’s not necessarily true.

If you are healthy and your diabetes is under control you may be able to become a blood donor. You should check with your doctor before you make an appointment to donate blood. 

Being a diabetic does not mean you can’t donate blood, but there are some factors related to your diabetes that could cause you to be deferred.  

Factors that may prevent a diabetic from donating

Blood sugar levels

If your blood glucose level is within your target range (set by your medical provider) and you are in good health, you should be fine to give blood.

You should not donate if you are having issues with your sugars and they are not in range, but it’s also a good idea to let your doctor know you wish to donate blood to get his or her recommendation.

Blood with too much sugar in it doesn’t store well.

Source of insulin

Those who have used bovine-derived insulin at any time since 1980 are ineligible to donate. This requirement is related to concerns about variant CJD, or mad cow disease.

Studies have shown that there is a small possibility that mad cow can be passed through blood transfusions.

Other diabetic medications, in general, won’t prevent you from giving blood, but there is a list of other medications that could cause a deferral. Please review our deferral list for more information.

Does it matter if I have Type 1 or Type 2 diabetes?

As long as your diabetes is well-managed and under control, you can donate blood. Having Type 1 or Type 2 diabetes does not make a difference. 

Tips for diabetics on how to prepare to give blood

In the days before your donation, strive to keep your sugar level within the normal range as determined by your medical care team. As with all blood donors, we recommend that you hydrate well the days before and after your donation and get plenty of sleep the night before. Find more pre-donation tips here. 

Monitor your blood glucose levels post-donation

Some Type 1 diabetics report slightly elevated blood glucose levels 3-5 days after donating. While your immediate levels won’t spike or bottom out due to donating, it is possible that donating blood may cause your A1C or HbA1c to be falsely lowered. This is thought to be caused by blood loss and accelerated red blood cell turnover.

Monitor your blood sugar levels after donating and make sure to keep your body nourished by increasing your fluid intake and consuming more iron.

Unlike insulin diabetic’s use, blood cannot be made in the factory and only comes from volunteer donors. If your diabetes is well-controlled you can give whole blood every 56 days or donate platelets every 7 days.

If you are ready to celebrate taking control of your diabetes and save lives. Make an appointment to give blood today. 

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