A new study has shown that frequent blood donation does not change a person's risk of developing cancer.
Researchers from the Karolinska Institute in Stockholm found no clear trend for an increased or decreased risk of cancer with increased donations.
While iron is a vital trace element for essentially all living organisms, too much iron has been implicated as a possible risk factor for certain cancers. If true, blood letting might be protective.
Conversely, blood cell proliferation after donation might increase the risk of malignancy. The interpretation of previous studies has been complicated by the fact that blood donors have a healthier lifestyle than most comparison groups. Therefore, blood donors should ideally be compared with other blood donors.
Gustaf Edgren, Ph.D., of the Karolinska Institute in Stockholm and colleagues performed a case-control study within a larger group of Swedish and Danish blood donors.
They compared the frequency of donations among 10,866 regular blood donors who developed malignancies with the frequency of donations among 107,104 regular donors who did not.
They found no clear trend for an increased or decreased risk of cancer with increased donations.
"In conclusion, we found that repeated blood donation was not associated with risk of cancer overall," the authors wrote.