If you want to live a long life, become a blood donor. That is the conclusion of a large Danish-Swedish study.
More than 1 million donors took part in the study, which showed that the risk of death decreases with the number of annual donations. For every extra unit of blood a donor gives, the death rate drops as much as 18.6 percent.
The cause may be that giving blood protects against cardiovascular disease.
But the science isn’t over it yet.
Donors generally healthier
In 2022, Dutch researchers analyzed the scientific literature in this area, and 9 of the 14 studies were found to report positive effects of blood donation.
But they didn’t look at the “health donor effect.” Donors are on average healthier than the rest of the population, which can lead to misinterpretations.
For example, the annual lower death rate in the Danish-Swedish study fell from 18.6 to 7.5 percent after taking into account the better health of donors.
While the positive effect of blood donation on the cardiovascular system may not be as great as first thought, blood donors are healthier in other ways too.
Studies show that good deeds are generally beneficial. For example, helping people in need leads to less stress and a better mood.