Stop Flushing Away Health Insights
Image generated using AI
By Matt Campbell, Mouser Electronics
Published February 5, 2024
Introduction
In the past decade, smart technology has transformed everyday appliances into connected pieces of the smart home. However, the bathroom has not seen drastic changes. Smart toothbrushes and scales are common, but the humble toilet has remained largely unchanged for the last century. Recent developments in sensor technologies, as well as an interest in health metrics, have finally kicked off the development of smart toilets.
Today’s high-end, spaceship-looking commodes offer quality-of-life improvements like night lights, heated seats, and automatic lids. While these features enhance the bathroom experience, they aren’t necessarily groundbreaking technology—just clever applications for existing tech. What makes the truly smart toilets special is their capability for advanced health metrics.
More Than Bells and Whistles
Every day we flush away a wealth of information about our health. The idea of testing waste may be unpleasant, but these tests can provide information about infections, certain types of cancers, diabetes, and many more diseases. During the COVID-19 pandemic, scientists tested wastewater for the virus and were able to monitor outbreaks by mapping the amount of the virus in the wastewater, combined with where the wastewater was coming from. Researchers at the University of Miami were even able to test wastewater to determine if a particular dorm on campus was having an outbreak.[1]
Advanced toilets contain onboard waste-sampling equipment, such as cameras to monitor the consistency of stool or the flow of urine. Future toilets may even be able to capture and process stool samples. Regular stool tests catch signs of colorectal cancer early, but they often involve embarrassing or unpleasant sample collection in a lab or mailing samples to a lab. Automating sample collection at home could make getting routine screens more palatable. Automation would also simplify long-term patient monitoring by providing regular updates to a patient's healthcare provider with no extra effort from the patient.
For patients with food allergies or sensitivities, a smart toilet paired with a food journal provides detailed insights on triggering foods. Many people with irritable bowel syndrome (IBS) keep food journals to help pinpoint the cause of flare-ups. If the food journal was in an app accessible by the toilet, then the toilet could compare what comes out to what goes in to give users important information on how their bodies respond to certain foods. With enough data, the application could even predict potentially triggering foods (Figure 1).
Figure 1: Paired with a food journal, smart toilets could help users with food sensitivities identify foods to avoid. (Source: PheelingsMedia/stock.adobe.com; generated with AI)
Continuous health monitoring is also an exciting trend for health- and fitness-conscious consumers. Health metrics excite people who are interested in improving themselves, and smart toilets provide a whole new world of metrics. For health-minded users, smart toilets could make suggestions on hydration and fiber intake, monitor glucose levels, and provide early warnings for things that may warrant a trip to the doctor. The kind of people who like to share every run and bike ride might even push for a social feed to share their bathroom activities and personal records with their followers.
What Makes a Toilet Smart?
Current health-monitoring toilets contain electronics adapted to fit existing toilets, but bespoke solutions could emerge as the technology matures. The current solutions include cameras to monitor urine flow and stool composition, mechanical arms to deploy urinalysis strips or "dipsticks," and wireless transmitters for securely sending data to the cloud.
Any camera application that inferences data based on captured imagery presents a great opportunity for machine learning. Machine learning algorithms can build user profiles and learn each person's norm to better understand deviations from the norm that might be worth alerting the user about. Paired with data from food journals or medical wearables, machine learning can build a holistic view of a user’s digestive health from an end-to-end perspective. The algorithm can help users track the effects of stress, sleep, and diet on their bodies.
Nutrition is extremely complex and contains so many variables that researchers have a hard time isolating those of interest. A machine learning algorithm could shine light on the black box of the human body and give users actionable insights for their diets. For example, such an algorithm could make real-time suggestions for diet adjustments for patients with IBS. If users consent to sharing anonymized data, it could even let users know foods to avoid based on data from similar users.
In addition to machine learning algorithms, traditional urinalysis strips provide instant, reliable results. Urinalysis strips contain a reagent that changes color based on the concentrations of parameters such as pH, glucose, protein, ketones, and blood. Urinalysis strips with multiple reagents are available off the shelf, offering ten or more different tests on a single strip. Optical sensors can interpret the color results of a multi-test strip, giving smart toilets the ability to quickly capture a wide variety of health metrics from urine (Figure 2). Users would get early notifications of conditions like urinary tract infections (UTIs), diabetes, kidney disorders, and pregnancy.
Figure 2: Healthcare providers can get a head start on routine screenings and diagnoses by using information collected in the bathroom. (Source: Kirsten Davis/peopleimages.com/stock.adobe.com; generated with AI)
Designers will need to decide how much to rely on toilets functioning as edge computers and how much processing should be done in the cloud. A toilet capable of running a machine learning program will have higher power requirements and may be prohibitively expensive for consumers. A toilet with cloud-based computing will need a secure connection and database that complies with global data privacy laws.
Designing for maintenance presents more challenges. When a smart toilet malfunctions, should users call a plumber or an IT technician? Manufacturers will need to have customer support, trained technicians, and replacement parts. Installation may require electrical work, as many bathrooms do not have an extra outlet near the toilet.
Challenges to Adoption
A critical step in smart toilet operation is identifying users. A toilet developed by researchers at Stanford University includes a fingerprint scanner on the flush handle to identify users as they flush.[2] However, this feature has limits: High-end toilets flush themselves, and people may not always be flushing for themselves (for example, in assisted living facilities). The goal of smart toilets is to be as unobtrusive as possible, so adding an extra step to verify users is counterintuitive and could be disastrous if someone having an emergency forgets their toilet login.
One of the biggest challenges for smart toilets is social rather than technological. People will have to be okay with their most sensitive data being analyzed. What goes on in the bathroom is a private affair, and waste analysis is usually reserved for specific diagnoses and not routine checkups. To put it simply, the ick factor will be the first major barrier to adoption. Cameras in toilets sounds like a nightmare from a cheap short-term rental, not a cutting-edge medical device.
Data privacy will be more important than ever before. Because the information smart toilets collect will be shared with healthcare providers, it will be protected as medical information. In the US, such data falls under the Health Insurance Portability and Accountability Act (HIPAA), which contains strict protocols on how patient data can be accessed and used. The last thing smart toilet users want is a breach of sensitive data, or targeted ads based on their bathroom habits. Wireless transmitters in smart toilets will need to send encrypted information to the database they’re connected to.
There are also ethical concerns with continuously monitoring people’s waste. Smart toilets could detect the presence of alcohol or prescription or illegal drugs that users may want to keep private. If you’re a guest in a home that has a smart toilet, is there a way to opt out of the smart features and turn it into a traditional toilet?
Finally, sensitive electronics in a toilet will need to stay calibrated and clean to maintain optimal performance. Electrical connections and components will need to be sealed to protect against moisture. Toilets are also not sterile, creating the potential for contaminated tests and false positives. Machine vision could identify waste and direct the toilet to intercept it before it hits the water. This would involve one or more cameras; small, ruggedized motors; and dedicated plumbing and chambers for sample processing. Once again, the greatest obstacle will likely be users allowing cameras and robot arms to closely watch them from below.
Conclusion
While we may not enjoy thinking about our waste, the real waste is flushing away valuable health information. Smart toilets offer exciting diagnostic and health metric opportunities. Early prototypes and experiments offer promising results, combining machine vision with traditional reagent-based tests. Regular monitoring could help catch early signs of a wide variety of diseases, helping users seek timely treatment. While the technology has made strides, one of the biggest barriers to adoption will be users needing to consent to having their most intimate data analyzed.
Sources
“Tracking Covid-19 through Wastewater,” US National Institutes of Health, March 23, 2023, https://covid19.nih.gov/news-and-stories/tracking-covid-19-through-wastewater-testing.
Hanae Armitage, “‘Smart Toilet’ Monitors for Signs of Disease,” Stanford Medicine, news release, April 6, 2020, https://med.stanford.edu/news/all-news/2020/04/smart-toilet-monitors-for-signs-of-disease.html.