Why Does Morning Coffee Make Me Poop?

Oat milk latte, shot of espresso, cold brew, or the classic mug of drip coffee. However you take your coffee, it's no secret people love an early morning caffeine kick. But why does the beloved brew sometimes make you poop?

Integrative gastroenterologist Marvin Singh, M.D., and functional medicine doctor Wendie Trubow, M.D., MBA, weigh in on why coffee often leads you to the bathroom and whether or not it's possible to manage that bodily reaction.

Is there a specific ingredient in coffee that makes you poop? Singh says this sensation might actually be caused by a variety of factors. "The warm temperature of the liquid1 may stimulate motility," he says, "and the caffeine also contributes to contractions of the bowel2." That said, although there have been a few studies, there isn't enough research to confirm any theories.

While caffeine might play a small role in making you poop, one study shows both caffeinated and decaffeinated coffee have an effect3. The study writes there was an "increase in motility index within four minutes after ingestion of both regular and decaffeinated coffee." In other words, both sped up the desire to poop.

"Also there are chemicals in coffee like chlorogenic acids that may contribute to the digestive process and stimulation of the bowel," Singh explains. Those acids are present in both caf and decaf varieties. 

According to Singh, "There are two major things that stimulate the GI tract: eating and waking up." So when you wake up and have a warm beverage early in the morning, it might be part of the reason you feel the need to poop shortly after.

But if you're drinking the coffee later in the day, the temperature probably won't make a difference. "The main thing you're removing by making coffee iced is the temperature," he says. "The acidic chemicals and other compounds in coffee may still contribute to having a bowel movement." 

If you're not willing to give up coffee altogether—and come on, who is?—Singh suggests avoiding drinking it first thing in the morning. "While it's not a sure thing, perhaps the timing and the amount of coffee you drink will alter bowel movements," he says. 

Additionally, if you're sensitive to lactose, swapping your dairy creamer for an almond or oat milk alternative might help reduce gas and bloating.

Unfortunately, Trubow says, "if you are responsive to coffee, it's unlikely that you can stop the effects if you drink it." If it's bothersome enough, you might try swapping your coffee for tea or warm water with lemon.