Flush Business

There's a specific kind of shame that only happens in a supermarket checkout line.

The trolley. The 24-pack. The walk from the paper aisle to the register.

The creeping certainty that every person in your peripheral vision is looking at you and knows exactly what you're about to do with your weekend.

Nobody says anything. Because everyone is buying the same pack.

Same biology, same silence, same unspoken agreement not to discuss it.

That silence has a dollar value.

And as of mid 2026, four hardware companies decided to start measuring it.

Serious Data

Doctors know what gut output reveals. Plebs get uneasy when having to discuss it. Even worse when you have to scoop it up and send your doctor a sample because you ate the MC Chicken that had been sitting in the fridge for three weeks.

The Bristol Stool Scale is a clinical diagnostic tool used globally, classifying stool into seven types from hard pellets to liquid.

Gastroenterologists use it to track Crohn's disease progression, diagnose IBS, and flag early signs of intestinal inflammation.

It's objective in a way patient self-reporting never is. Your gut doesn't dress things up or lie.

IBS affects between 10 and 15 percent of the global population. Crohn's disease and ulcerative colitis combined affect millions more, most of whom manage without any ongoing objective data between clinic visits.

These are not fringe conditions. People managing this do it the same way a diabetic manages blood sugar: constantly, with limited real-time information, and a lot of guesswork.

The existing tool for capturing that data is a stool sample kit.

I've done this once. You receive a collection kit. A paper sheet that drapes across the toilet bowl. You produce, then scoop a sample into a container, seal it, bag it, and walk it to your doctor's office like you're carrying something you can't believe you're carrying, handing it over while the nurse rushes to get gloves to even touch what your doctor told you to bring in.

The whole process takes 15 minutes and is the least dignified 15 minutes available.

That same test, sent by mail, is now a $149 consumer product. Viome built a business around it. RNA sequencing of your stool sample, 2-4 weeks for results, personalised food and supplement recommendations on the back end. They've raised millions off it, put the Gut Intelligence Test into 200 CVS stores, and processed over a million samples.

The clinical version is Cologuard, a stool DNA test for colorectal cancer screening, priced at around $700 per test and covered by Medicare every three years. It exists because stool tells you things about colorectal cancer risk that a blood test can't.

Urine is a separate story from a different angle.

According to Withings, who spent seven years building a urine analysis lab the size of a pebble that looks like a clam, urine contains over 3,000 metabolites that mirror nutrition, hydration, hormonal balance, and metabolism. A goldmine of data that has long remained underused, confined to occasional laboratory tests far from real life. Your GP orders a urine panel when something's wrong. A toilet device could run one every morning before you've had coffee.

The data is real and clinically meaningful. Right now it's mostly generated through kit-based testing and occasional GP visits.

A 40 Year Old Idea

The smart toilet is not a 2025 invention.

Japanese patent filings on toilet-based urine analysis go back to 1982. TOTO developed a toilet that could measure urinary sugar and hormone levels as far back as the early 2000s, but demand was low. The product cost several thousand dollars, required replacing the whole toilet, and lived in a world with no smartphone to send data to and no subscription model to build a business around. The technology worked but the market didn't exist.

Stanford University published a paper in Nature Biomedical Engineering describing a mountable toilet system capable of running a 10-parameter urinalysis, classifying stool on the Bristol Stool Scale using computer vision, measuring urinary flow rate and stream volume, and flagging biomarkers associated with cancer and a range of chronic conditions. The author noted that unlike wearables, "you can't take it off." The toilet's clinical advantage is guaranteed compliance, no behaviour change required.

To identify which household member produced which data, the Stanford team used a fingerprint scanner on the flush lever and a second camera positioned to identify users by the unique creases of their anus. "We know it seems weird, but as it turns out, your anal print is unique."

This appeared in a peer-reviewed academic journal. Not a startup pitch deck. Nature Biomedical Engineering. The concept dated back over 15 years before publication. The technology has been in labs and patent filings for over four decades. What failed each time was not the sensor. It's everything else required to turn a sensor into a business.

Toilet Business

Eight Sleep did not invent sleep tracking.

Fitbit introduced automatic sleep tracking in 2009. Wrist actigraphy, movement-based sleep monitoring, existed in clinical settings since the late 1980s. Beddit was measuring sleep via an under-mattress sensor before Eight Sleep launched, and Apple bought them in 2017. SleepNumber had smart bed features before Eight Sleep sold its first Pod.

What Eight Sleep built was the right sleep monitor, at the right time, with the right model.

Eight Sleep's Pod product line has generated over $500 million in sales, with revenue growing tenfold since launch. The Pod 5 starts at around $2,200. The autopilot subscription runs around $20 per month. Hardware margin is probably 40-50 percent at that price point. The business is hardware as customer acquisition, subscription as the actual revenue, and a proprietary dataset as the long-term asset. You can subscribe to your bed, why not your toilet?

Oura raised a $900 million Series E in October 2025 at an $11 billion valuation. It's a ring. It retails at $299-$349, manufactured for a fraction of that, with a $6 per month subscription. The ring is not the business. A decade of continuous biometric data per user is the business.

WHOOP pushed the model further. The device is free on some plans. The subscription is the product. No display, no screen, just a strap that tells you your recovery score and strain load. The former Chief Technology Officer of WHOOP, John Capodilupo, co-founded Throne, a startup that clips a camera to your toilet bowl and tracks what comes out.

The pattern across all of them, pick a universal human behaviour, find sensing technology that's been around long enough to be reliable but hasn't been packaged correctly, build continuous passive monitoring around it, add a subscription, start with biohackers and athletes, pursue clinical validation, expand. Sleep. Activity. Heart rate. Recovery.

TOTO failed in 2003 because the sensing technology was only one part of the equation. The subscription model, the smartphone, and a culture of tracking personal health data didn't exist yet.

Now they do.

Ramping Up

In the last year, four products have hit shelves. All launched between October 2025 and early 2026. The category arrived without a press cycle, and the stigma is hard to beat.

After many years of R&D, Withings launched a miniaturised urine analysis laboratory that integrates directly into the toilet environment. The U-Scan sits in the bowl. A thermal sensor detects urine, draws a sample, and runs it through chemical sensors embedded in an interchangeable cartridge.

No camera. No optics. This version of the product doesn't need to see anything because urine analysis can be done with chemistry.

But this is urine only. Stool is not in scope.

Kohler, the bathroom fixtures company, launched a health division. Dekoda was its first product. A clip-on device using optical sensors, spectroscopy, and machine learning to inspect both urine and stool, tracking hydration, gut health indicators, and flagging traces of blood.

The blood detection matters. Blood in stool can indicate all manner of bad things. A passive daily alert on that is genuinely meaningful clinical information, not wellness theatre.

Kohler also told users their data was protected with end-to-end encryption. In December 2025 a security researcher pointed out that wasn't true, it was standard transport encryption, the same thing that secures a normal website. Kohler quietly fixed the website copy after TechCrunch called. Worth remembering next time a health gadget promises you privacy in a marketing paragraph.

Throne launched recently with a 2MP downward-facing camera and a microphone mounted to the rim, using computer vision and acoustic sensors to track stool consistency, colour, frequency, and urological function.

The multi-sensor approach is deliberate. If the camera detects liquid stool, the microphone data can confirm it based on sound patterns. The combination improves reliability over a single sensor alone.

Clinical research partnerships are underway with the University of Washington and the University of Chicago. FSA and HSA eligible, meaning the IRS has categorised this as a health device. White toilets only, rim under 2.25 inches.

The user identification problem, how does the device know whose data is whose without a fingerprint scanner or an anal print database, is solved via Bluetooth proximity. Throne activates when you sit down and pings your phone's Bluetooth to identify which paired account is in the room. It never turns on for guests. A houseguest using your bathroom isn't tracked. Two household members with their own profiles get their own data.

Elegant solution to a problem Stanford needed a camera pointed at your butthole to solve.

TOTO, the company that tried and failed to commercialise toilet health monitoring in the early 2000s, is back. The Neorest includes a Stool Scan function that automatically measures shape, colour, and amount of stool and pushes results to the TOTO Wellness app.

Only issue is it's still a full toilet replacement, not a retrofit clip. Higher price, higher installation friction. The company with the longest history in this category, the widest distribution, and the deepest manufacturing capability in the world is treating this as a serious product extension after a 20-year gap. When the pioneer returns, it usually means the timing shifted.

A fifth showed up two months after the others. Vivoo, a Turkish company that already has 300,000 users on a urine test strip business, launched a toilet sensor at CES 2026 for $99, about a quarter of what Throne charges. Four became five before anyone finished writing about four.

That's the loud version. There's a quieter one running in parallel. OutSense, an Israeli medtech company, has had a version of this clipped to hospital and care home toilets since 2016, patents granted in the US, Europe, Japan, and China for detecting blood in stool, still working through an FDA pathway. Toi Labs has been doing something similar for senior living facilities since 2018, deployed in over fifty communities, TOTO is one of its investors. Neither one ever ran a consumer press cycle. The four above are just the first four that had to.

Snapshot versus stream

Viome is the snapshot business. Send in a sample, get RNA sequencing, receive dietary recommendations in two to four weeks. Over a million samples processed. Valuable, but roughly equivalent to taking your blood pressure once a year and declaring yourself monitored. Viome isn't the only one running that play either, ZOE and Tiny Health do versions of it for different audiences, same mail-in model underneath.

Toilet hardware is trying to be the stream business. The same signals gastroenterologists use to track IBS, Crohn's, and UC, frequency, consistency, colour, blood presence, captured passively without the patient doing anything new. That's the pitch, anyway.

Two very different products, but also two different purposes.

Viome answers: what is living in my gut right now, and what should I eat?

Throne or Dekoda answers: what did my body do this morning, and how does that compare to last Tuesday?

A gastroenterologist would want both. The behavioural stream for ongoing monitoring (and possibly a talking-to about watching reels for 40 minutes three times a day on the throne). The molecular snapshot when something shifts and you need to know what changed in the microbiome.

Porcelain Thoughts

Throne captures stool colour, shape and consistency, stool frequency, urinary colour, urinary flow rate, session duration. Everything a camera and microphone can see and hear. What it cannot capture: urinary pH, ketone levels, specific gravity, vitamin C concentration, calcium levels, or any molecular marker.

It sees the bowl. It does not test it.

Withings captures pH, specific gravity, ketones, vitamin C, calcium. Genuine biochemical markers from urine. What Withings cannot capture is anything about stool, or any visual signal about urine beyond what passes through the microfluidic sensor.

The combination product, optical stool analysis plus chemical urine analysis in a single device, doesn't exist in the consumer market.

Academic research explains why stool molecular analysis at the bowl remains unsolved: stool must typically be homogenised before chemical analysis, and assays requiring complex equipment, such as nucleic acid or microbiome sequencing, are difficult to implement within the form factor and constraints of a toilet-based device. The molecular layer is still a lab problem. The visual layer is solvable. The chemical urine layer is solvable. Combining the second two hasn't happened yet.

Bowlsthetics

Throne looks like a paperback book clipped to the inside of your toilet rim, with a 13-foot USB-C cable running across the bathroom floor to the nearest outlet.

That cable lives there. For the month between charges, it is never invisible. And when a guest uses your bathroom, they see a plastic box on your toilet and a cable running across your floor.

The question it generates is not "I want that." It's the other question.

Compare that to an Oura Ring, or an Eight Sleep Pod visible on a bed. Both generate genuine curiosity and product desire. Throne generates the same surprise with a completely different emotional outcome.

The Oura Ring is jewellery that happens to be a computer. Throne is a camera that happens to clip to your toilet.

To Bidet, Or Not To Bidet

In Japan, over 80 percent of homes use bidet toilet seats.

In the US, 45 percent of high-income households have already adopted bidet solutions. The COVID-19 toilet paper shortage drove an adoption shift in North America that hasn't reversed. Unlike Peloton, unlike Zoom, bidet sales held.

The US bidet market was valued at around $6 billion in 2024 and is growing at around 6 percent annually.

A premium electric bidet seat is already plugged into a wall outlet, fitted with a seat pressure sensor to detect occupancy, positioned with a direct sightline into the bowl from the underside of the seat, and justified by comfort and hygiene as the primary purchase reason. If you put health monitoring sensors into that form factor, the health monitoring becomes the subscription hook, not the pitch.

Right now: "I have a device that monitors my bowel movements" has never successfully opened a dinner party. "I got a Japanese seat, it's incredible, and it also tracks your gut health" just might.

Every successful wearable health device has a primary justification that isn't clinical data. Eight Sleep is temperature comfort. Oura is a piece of jewellery. Garmin is a sports watch. The health monitoring is the hook that creates the subscription. None of them lead with biometrics.

Nobody has built this product. TOTO is closest with the Neorest, but that's a full toilet replacement costing thousands and requiring a plumber. A retrofit bidet seat version, compatible with any existing standard toilet, self-installed, in the premium bidet seat price range, doesn't exist. Whether that's a gap worth filling or a gap that exists for a reason, hardware margins on a seat are not the same as hardware margins on a small clip, is a separate question.

GLP-1 in the wild

GLP-1 prescriptions have more than tripled since 2020. As of 2026, 11.8 percent of US adults reported having used GLP-1's.

GLP-1 drugs slow gastric emptying significantly. The gut side effects, nausea, constipation, diarrhoea, erratic motility, are among the most commonly cited reasons patients discontinue. Half of patients quit within a year. Only 14 percent remain on Wegovy after three years. The gut response varies enormously between individuals and between dose changes, and patients currently have no passive monitoring tool to understand what the drug is doing to their gut between clinical visits.

A toilet sensor with a GLP-1 mode, established pre-medication baseline, cross-referencing dose timing with daily bowel data, flagging when gut patterns shift at dose increases, would be a product with a large, high-income, highly motivated, fast-growing user base that exists today. Nobody's built that mode yet either. Tie a health claim to a specific medication and the FDA conversation gets more complicated, which might be exactly why it's still sitting on the table.

Missing Seats

The devices that launched in 2025 and 2026 have solved the sensing problem.

Consider what Eight Sleep actually delivers. You don't read your sleep data. The mattress cover reads it for you and changes the temperature before you wake up. The output is not a dashboard. The output is that you feel better in the morning. The data is invisible. The result is the product.

Every current toilet product delivers a dashboard.

Your hydration score is 68. Your Bristol Stool Scale average this week was 4.2. A trend line showing your gut was less stable in February.

What does that mean?

What do you do with it?

The answer, in most current apps, is consult the included dietitian session, or look at the graph and draw your own conclusions.

What people actually want from this category is not data. It's explanation.

Why do I feel bloated every Tuesday? Why has my energy been low for three weeks? Is the medication doing anything? Is the new diet working? The gut is one of the most common sources of unexplained chronic symptoms and the people who would pay $500 for a toilet sensor are largely the people who have already tried everything else and still don't have an answer.

Gut data that requires interpretation is homework. Most people won't do homework consistently.

The stigma compounds this. Buying an Oura Ring means you tell people you track your sleep. That's a completely normal sentence in 2026. Buying a Throne means you tell people you have a toilet sensor monitoring your bowel movements. Nobody is volunteering that at dinner.

Eight Sleep isn't a mattress cover brand. It's a sleep fitness brand. The cover is a detail.

The categories that broke through, sleep, recovery, activity, all landed on products people talk about without mentioning the data. The thing they're reaching for. Nobody's found that thing yet for the toilet. The sensing problem and the story problem look like they need separate solutions, and right now every product on shelves is trying to solve both with the same piece of hardware.

The four-decade gap between TOTO's failed prototype and this year's product launches suggest the timing shifted on the hardware side. What happens on the intelligence side, the reason anyone stays subscribed, is an open question.

So What.

Four products in market. Two from established companies with manufacturing scale. One with WHOOP's former CTO and clinical academic partnerships. One from the company that tried in 2003 and now has 20 additional years of bathroom hardware distribution behind it.

The unit economics make sense on paper. Hardware at $400-600, subscription at $70-180 per year, in a model that adjacent categories have proven works when the product actually changes behaviour.

What hasn't been proven, whether the behaviour changes.

Whether the dashboard turns into something people come back to daily.

Whether the stigma around talking about toilet data loosens the way sleep tracking did, or stays just uncomfortable enough to keep this a niche.

The addressable market isn't small. IBS alone is 10-15 percent of the global population. GLP-1 users are growing from 10 million to potentially 30 million in the US by 2030. Crohn's and UC patients manage between clinic visits on memory and instinct. These are people with a specific, recurring, disruptive problem that existing products don't solve. Not wellness tourists.

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Shout out to all the legends I've ripped info from for this piece:

Withings | Engadget | Gadgets & Wearables | TechCrunch | Engadget (Throne CES) | Gizmodo | Smithsonian | Fierce Healthcare | Crunchbase | RAND | JP Morgan | HealthVerity | Wellworthy | Japan Today | CNN Business