The U.S. Federal Drug Administration has banned gay men from donating blood since 1983, when it was discovered that HIV, the virus that causes AIDS, was being transmitted through transfusions.
Eliminating the ban could bring in roughly 615,300 pints (291,145 liters) of blood annually, while allowing donations from gay men who had not had a sexual partner in a year could yield 317,000 pints (150,000 liters), the study estimated.
With a five-year policy, nearly 300,000 pints (142,000 liters) could be collected, according to the study by the Williams Institute on Sexual Orientation and Gender Identity Law at the University of California, Los Angeles.
"The American Red Cross suggests that each blood donation has the potential to be used in life-saving procedures on three individuals," said study co-author Ayako Miyashita. "Our estimates suggest that lifting the blood donation ban … could be used to help save the lives of more than 1.8 million people."