The future of gastrointestinal medicine could be something most people would find bloody awful: drinking one’s own blood.

A new study in the United European Gastroenterology Journal suggests that drinking one’s own blood may help doctors detect inflammatory bowel disease — including Crohn’s disease and ulcerative colitis — in a less invasive manner than an endoscopy.

The “vampire study” asked 12 women and four men in Zurich, Switzerland, to ingest their own blood on two occasions one month apart.

It seems drinking blood increases the levels of a protein called calprotectin that is found in feces. Researchers at the Centre for Gastroenterology and Hepatology in Zurich believe the presence of the protein can be a marker for intestinal bleeding.

Most of the participants drank their blood; a few ingested it via a nasogastric tube that sent it straight to their stomachs.

It wasn’t pleasant for many: Live Science says about half the participants suffered painful nausea and about 30 percent suffered diarrhea or constipation after ingestion.

Oh, and the poop was unusually dark after the blood drinking.

The end result ― figuratively and literally ― is that calprotectin levels increased after drinking blood, which means that doctors could look for high levels of the protein as a sign of intestinal inflammation.

While the protein can signal disease, lead study author Dr. Stephan Vavricka told Live Science that doctors need to take account of calprotectin levels to determine whether the patient is bleeding and not just suffering inflammation.