The poor economy is one reason why more people are working as test subjects.
Charlotte Lasallas has been cut, drugged and pushed to the limit, all in the name of science.
On Monday, she had her lungs and muscles tested in a clinical trial to help NASA figure out a way to increase bone density in astronauts.
"I think I get $300 for this one. It's not about the money, but it's obviously nice, especially for me because I go to school so much, and I go for long hours at a time, every day. It's nice to make money somehow," said Lasallas.
The U.C. Irvine student says she initially became a human guinea pig to learn more about a medical condition in her family. She was recruited in her nursing class, and is now on her second medical trial.
Cooper says he has seen an increase in the number of patients walking through the doors at UCI's Clinical Trial Research Center. Although some are motivated by money, he says, others come looking for a free answer to a health problem.
"We have to be really, really careful that we explain to individuals (who) participate in clinical trials that this is research. We don't know the answer yet; that's why we're doing the study," said Cooper.
Officials say the patient payments can come from drug companies, the government and groups like the American Heart Association. The prices are set by the institutional review board, and an independent group of doctors and researchers.
Nurses say college students who give blood can make $40 every couple of weeks.
But Lasallas says she has another agenda; she wants to be part of medical history.
"I feel like I'm one of the few who actually aids in studies that are actually going to do something in the world. They're going to change a lot of different aspects of medicine and sports and working out. It's important to me," said Lasallas.