Is donating blood good for the donor too?

In Italia, around 1.67 million volunteers donate blood and plasma every year. In 2024, there were over 3 million donations, enabling blood transfusions for around 640,000 patients and the treatment of thousands of people every day with plasma-derived medicines. Donation is free, anonymous and voluntary. The benefits of this act for those receiving blood are beyond question: for many patients, there is no alternative. However, donors often do so in the belief – fuelled by newspaper articles or word of mouth – that they will derive a direct health benefit from it. Is this really the case? Let’s see what the scientific evidence says.

To some extent, yes, but not for the reasons you most often hear cited. The most tangible and well-documented benefit is preventative: every time you give blood, you undergo a series of free health checks. Before donating, your blood pressure is measured, your haemoglobin level is assessed and you complete a health questionnaire; sometimes an electrocardiogram is also carried out. The blood sample taken is then subjected to comprehensive blood tests, including a complete blood count, tests for HIV, hepatitis B and C, and syphilis; for regular donors, tests are also carried out for cholesterol, triglycerides, creatinine and ferritin. This is a comprehensive health check-up that can reveal conditions of which the donor was unaware. In this sense, donating blood is also an opportunity for preventive healthcare. We have discussed these tests and the safety of the procedure for the donor in the factsheet ‘Can we all give blood?’, and the difference between giving whole blood and donating plasma in the factsheet ‘Is donating plasma just as important as giving whole blood?’.

Another aspect highlighted in some observational studies concerns psychological well-being: many donors report a sense of satisfaction linked to the act of helping others, an effect that has been documented more generally in the context of voluntary work.

This is one of the most widely held beliefs, but the available scientific evidence does not support it. There are two underlying biological hypotheses. The first is that donating blood regularly reduces the body’s iron stores: excess iron is thought to contribute to the formation of molecules that damage the walls of the arteries, promoting the development of plaques over time. The second is that donating blood reduces its viscosity, making it more fluid and less likely to form dangerous clots. Through one of these two mechanisms, or both, donating blood may lower the risk of heart attack and stroke.

A systematic review published in 2022 analysed 44 studies on the subject. Among the highest-quality studies, the majority did indeed report a protective effect of blood donation on the cardiovascular system. The authors caution, however, that these results may be skewed by the so-called ‘healthy donor effect’: in order to donate, one must pass a medical screening each time; therefore, donors are, by definition, people who are already in good health, and it is difficult to distinguish the actual benefit of donation from that which already existed before they began donating. The overall quality of the available evidence is therefore considered insufficient to draw definitive conclusions, and the authors conclude by reiterating the need to conduct higher-quality randomised controlled trials on this subject.