The American Journal of Human Biology published a study suggesting that people with multiple tattoos have a stronger immune system.

“Tattooing may stimulate the immune system in a manner similar to vaccination to be less susceptible to future pathogenic infiltration,” the study states.

The Huffington Post reports that for the study, University of Alabama researchers collected saliva samples from 29 volunteers before and after they received tattoos. Nine of the subjects were getting tattooed for the first time.

The saliva samples were needed to test for levels of immunoglobulin A, which is an antibody relating to gastrointestinal systems and respiratory systems, along with cortisol, which is a stress hormone that suppresses immune responses.

“Immunoglobulin A is a front line of defense against some of the common infections,” Christopher Lynn, associate professor of anthropology at the University of Alabama, said.

In the United States, one in five adults have at least one tattoo. This new study might encourage more people to get multiple tattoos not only for aesthetic reasons but for health reasons as well.

The study found that, of all nine first-time tattoo recipients, immunoglobulin A levels declined at a much more significant rate than those with multiple tattoos. The people who already had tattoos had an immune system that was able to handle that kind of stress.

Despite the study’s findings, Lynn states that although multiple tattoos could improve a person’s immune system, a first tattoo could actually make someone more susceptible to illness.

“You can catch a cold because your defenses are lowered from the stress of getting a tattoo,” Lynn said. Once your body returns to equilibrium, however, Lynn adds that “if you continue to stress your body over and over again, it [your equilibrium] adjusts its internal set points and moves higher.”

Whether tattoos actually can solve any real medical problems is still undetermined, but Lynn hopes to at least remove the negative stereotypes surrounding them. “We’d like to take tattoos out of the negative subcultural niche of bikers, sailors, and risky behavior,” Lynn said.

In Michigan, an area tattoo artist is doing just that and even providing a charitable service.

AOL reports that Carrie Metz-Caporusso, a tattoo artist at the Lucky Monkey tattoo parlor in Ann Arbor, held a charity fundraiser in support of those suffering with the water crisis in Flint.

Metz-Caporusso designed a specialty heart tattoo a droplet of water. Each tattoo — called Water Hearts for Flint — was priced at $50 and 100% of the proceeds will go to the Flint Child Health and Development Fund.