Effects of blood donation on cardiometabolic markers: a randomized sham-controlled trial

Researchers randomly assigned adults to either donate blood or have a sham procedure, which looked like a donation but removed little or no blood. They measured blood pressure, cholesterol, blood sugar, and other cardiometabolic markers, meaning measurements linked to heart disease and diabetes. Regular blood donation did not meaningfully improve these measures compared with the sham procedure. The study tested health markers, not whether donation prevents heart attacks or diabetes.

What this means for you: There is no good reason to donate blood solely to improve your heart or metabolic health. Donate if you want to help others and are eligible, but do not expect major personal health benefits from it.