This month, three separate studies all published in Nature Medicine and Science have shown that putting young blood into older mice helps reverse both the mental and physical symptoms of aging. Specifically, memory, endurance, muscle strength, and sense of smell improve. These findings could open new ways to treat conditions ranging from impaired mobility to Alzheimer’s disease.

“The changes are astounding in terms of rejuvenating the mice both in the periphery of the body and in the brain,” said Harvard professor and director of the Genetics and Aging Research Unit at Massachusetts General Hospital Rudolph Tanzi. “I’m kind of blown away, really.”

At this point it’s unclear why putting young blood into old mice makes such a big difference. But scientists suspect it has to do with the blood’s proteins. Scientists at the University of California San Francisco and Stanford University tested putting just the blood plasma (where proteins and other solids are stored) into the elderly mice and found the same results. Then they tried heating the plasma, which deactivates its proteins, before giving it to the mice. This time no benefits were observed.

According to Bradley Wise, chief of the National Institute on Aging’s Neurobiology of Aging Branch, it’s unlikely that seniors will ever be administered transfusions of young human blood. It’s much more likely that scientists will identify the individual proteins that cause the reverse aging affects and develop treatments based on them. Either way, it’s an exciting area of research that could potentially bring about huge changes in the battle against age-related deterioration.