Scientists at Stanford University have developed a “smart toilet,” complete with anal print recognition technology (more on this later), that can study your pee and poop to detect early warning signs of cancer and other red flags. 

Reported in the journal Nature Biomedical Engineering, the toilet uses pressure and motion sensors, test strips, and even video cameras to analyze the flow and biochemical composition of the pee. When it comes to “number twos,” the toilet uses these tools along with machine-learning algorithms to study the poop's structure and gauge whether the stools show any indication of health conditions.

"Our concept dates back well over 15 years," Professor Sanjiv “Sam” Gambhir, lead study author and chair of radiology at Stanford Medicine, said in a statement. "When I'd bring it up, people would sort of laugh because it seemed like an interesting idea, but also a bit odd."

Indeed, pee and poop is no laughing matter. You can learn a lot about a person’s health by studying their waste products. For example, stool analysis is important for diagnosing gastrointestinal disorders, including poor nutrient absorption, pancreatitis, infections, inflammatory bowel diseases, and cancers. This new technology can detect a range of disease markers in stool and urine, including those of some cancers, such as colorectal or urologic cancers. 

The toilet automatically carries out these tests and builds up a profile of each toilet user. It can identify a specific person using fingerprint scanning or – nope, we’re not joking – a camera that scans their anus. "We know it seems weird, but as it turns out, your anal print is unique," explained Gambhir. The data is then sent to a cloud-based system for safekeeping (which the researchers assure is very secure).

Unlike standard diagnosis tests, the smart toilet is an all-in-one device that can easily become integrated into peoples’ everyday routine, just like a wearable technology such as smartwatches. “The thing about a smart toilet, though, is that unlike wearables, you can't take it off," Gambhir added. "Everyone uses the bathroom – there's really no avoiding it – and that enhances its value as a disease-detecting device."

It isn’t yet clear how effective the smart toilet would actually be at improving the health of its users. After all, the researchers point out that previous attempts to use new technologies to monitor a person’s health have a bad track record of providing useful data that’s utilized by clinicians. Along with integrating a wider variety of diagnostic tests into the toilet, the researchers hope to see a large clinical trial to assess its efficacy at diagnosing disease in the real world.