I have a great fondness for schlocky black-and-white monster movies and have seen hundreds of them, but have yet to come across a flick called Dracula Meets Ponce de Leon. But that plot is playing out in real life, as some merchants are offering young-blood plasma transfusions that supposedly reverse or slow aging.

The FDA cautions against trying this, and if that’s inadequate incentive, your accountant advises the same. The treatment comes at $8,000 per intravenous session. The FDA states there is “no proven clinical benefit of the infusion of plasma from young donors in the prevention of conditions” that companies offering the transfusions claim to treat.

Some studies indicate that plasma transfusions may be beneficial – though that’s far from certain – but even if real, those advantages do not include arresting the aging process. Angela Chen of The Verge interviewed Michael and Irina Conboy, whose studies revealed possible benefits, but their research dealt with neither  humans nor transfusions. Meanwhile, the biotech company Alkahest is testing a plasma product on Alzheimer’s patients, but the results are still unknown and the goal is not to be eternally young. By contrast, those hawking the Fountain of Youth in plasma form transfuse patients with donations from the young and purport that the donor’s vim and vigor comes with it. But again, there has been no adequate plasma screen, so to speak.

Most research on young blood transfusions has been conducted in mice and the results are mixed. But even when the data seems promising, researchers are still unsure of the long-term results. Moreover, many times developing products look good in lab but fail to translate into human use. Along those lines, Nicole Westman wrote in Popular Science that research on rats has shown that the older ones benefit from a supply of younger blood, but most of those studies use a technique which surgically joins the circulatory systems of the animals. This means when the younger blood flows into the older animals, the rodent recipients also benefit from accessing the younger rats’ organs and systems.

Jesse Karamzin, founder of the transfusion company Ambrosia asked Inverse’s Sara Sloat, “If it works so much in mice, could it work in people as well?” However, much of the research that Karamzin is basing his optimism on was conducted by Tony Wyss-Coray, who has not endorsed the practice of trying it on people. Wyss-Coray injected mice with plasma from other mice and from people, but doesn’t see the benefits extending to human-to-human transfusions. He cites the lack of evidence it would work and he thinks it unethically raises a false hope.

By contrast, he founded Alkahest in hopes of developing drugs from plasma transfusion research instead of selling the plasma itself. The goal is to improve the quality of life as opposed to the quantity. He seeks not a Fountain of Youth but a way to conquer debilitating diseases that accompany aging.