The healthy donor effect and survey participation, becoming a donor and donor career

Researchers compared blood donors with people who did not donate, including people who answered health surveys, started donating, and continued donating over time. They examined whether donors were already healthier before their first donation. The study looked at the “healthy donor effect,” meaning that donors may seem healthier because healthy people are more likely to volunteer. The findings suggest that survey participation, becoming a donor, and having a long donor career can all select for healthier people, making it difficult to prove that donation itself improves health.

What this means for you: This does not show that donating blood makes you healthier. Donate if you want to help others and are eligible, but do not treat blood donation as a health treatment.