A Harvard Gastroenterologist Makes the Case for Ditching Toilet Paper

Most Americans have never seriously considered owning a bidet. But a growing number are curious — and a Harvard-trained gastroenterologist is here to answer all the awkward questions they've been too embarrassed to ask.

The Doctor Who Owns One — and Wants You to Know About It

Dr. Trisha Pasricha is the "Ask a Doctor" columnist for The Washington Post, an NIH-funded, double-board certified internal medicine physician and gastroenterologist at Beth Israel Deaconess Medical Center, where she directs the Institute for Gut-Brain Research — and an assistant professor of medicine at Harvard Medical School. She's also, as she freely admits, a proud bidet owner. Bidet owners, she jokes, are obnoxious — they need the world to know they have one, whether anyone asked or not. She knows this because she is one of them.

Pasricha says she's received so many questions from people who are bidet-curious but not yet bidet-ready. Her column, published on June 29, takes those questions head-on — from "could dirty water splash back at me?" to "how does it even know where to spray?" — and delivers answers grounded in medical science rather than bathroom humor. Her goal is to inject humor into her columns while offering straight talk about topics most people consider embarrassing.

What the Science Actually Says

Bidets are gentle and hygienic, and according to research, the hands of people who use bidets have fewer microbes than those who wipe. That's not a trivial finding. Fecal bacteria is a leading cause of urinary tract infections, especially in women, and traditional wiping can spread bacteria from the anal area toward the urethra.

Doctors emphasize that the skin in sensitive areas is delicate. Dry toilet paper acts like sandpaper, causing micro-tears and irritation. Water, however, provides a thorough, non-abrasive clean that paper simply cannot replicate. For people managing hemorrhoids in particular, the difference is significant. When hemorrhoids flare, even simple routines can feel daunting — the itching, burning, and tenderness make friction painful. A study published in the Journal of Korean Medical Science found that low to medium warm water pressure from bidets helped promote blood circulation and relieve anorectal pressure — exactly what hemorrhoid patients need.

The Financial and Environmental Upside

Bidets are commonplace in many areas of the world — including nations in Asia, Europe, and South America, as well as northern Africa — and appear to be gaining popularity in the United States. The 2020 pandemic-induced toilet paper shortages sparked unprecedented interest in bidets among American consumers, and that curiosity hasn't faded. The global bidet and bidet-seat market is around $4.16 billion in 2025 and still growing around 4–12% per year, depending on the segment.

The financial case is straightforward. The average U.S. household of four spends $200–$400 per year on toilet paper. After installing a bidet, most users reduce toilet paper consumption by 75–80%, and the payback period for a family is typically just 2–4 months — after which the household saves $150–$300 per year indefinitely. The environmental math is equally compelling. A typical roll of toilet paper requires 37 gallons of water to create. Americans use about 36.5 billion rolls of toilet paper each year, which requires cutting down 15 million trees.

How to Actually Use One

Some bidets attach to your toilet, either affixed to the side of the bowl or with a detachable hose. Other bidets are standalone fixtures that resemble a low sink. Entry-level bidet attachments are surprisingly affordable, ranging from just $25 to $100, and most people spend 30 minutes or less on a simple setup: turn off the water, attach a T-valve to the existing water line, connect the hose to the bidet, and tighten a few screws.

Reading the bidet manual and following directions on proper cleaning and maintenance matters. "Proper operation is important," notes one gastroenterologist. "If the water heater malfunctions, the water could deliver scalding hot or shockingly cold water." If a bidet gets contaminated, germs can find a way into the urinary tract, vagina, or cracks in the skin — so regular cleaning of the nozzle is essential. For most people, though, the adjustment period is short, and the converts tend to be vocal. As Dr. Pasricha would tell you: once you join the club, you'll probably never stop talking about it