Everyone is certainly entitled to his or her own opinion, but a new study has proven surfers to be shitty people—in a literal sense, at least.

Conducted by the University of Exeter and published in the journal Environment International, the UK-based study found that surfers were three times more likely to have antibiotic-resistant E. coli in their guts than non-surfers. With surfers swallowing an estimated ten times more seawater than the average beachgoer, scientists were curious as to whether surfers were more vulnerable to bacteria that pollute seawater. After examining the stools of 143 local surfers and 130 swimmers throughout England and Whales, the researchers found that 13 of the 143 (9%) sampled surfers were colonized by antibiotic-resistant bacteria, compared to just four of 130 (3%) of non-surfers.

Furthermore, the Exeter study, appropriately titled "The Beach Bum Survey," points out that surfers–because they’ve ingested E. Coli-laced saltwater–are at risk of spreading dangerous bacteria to others.

Antibiotic-resistant bacteria—which often finds its way into coastal waters as untreated human sewage and fecal matter that drains into the ocean—are of growing concern among both the environmental and medical communities. Recently, the United Nations Environment Assembly conceded that the spread of antibiotic resistance in the environment is one of the world’s greatest emerging environmental concerns. And The World Health Organization has warned that the world is facing the possibility that antibiotics could no longer effectively kill simple, and previously treatable, bacterial infections.

While the researchers who carried out the study say they don't wish to discourage people from surfing, University of Exeter's Dr. Will Gaze, who supervised the study, says that it is important to understand the risks involved. "We now hope that our results will help policy-makers, beach managers, and water companies to make evidence-based decisions to improve water quality even further for the benefit of public health," Dr. Gaze told Science Daily.

Any Southern California surfer who suffered through the beach closures of this past week can attest to the dire need for runoff-related policy changes. For now, when entering the water, it might be a good idea to keep your mouth tightly shut. For your own benefit—and everybody else's.