Plain as they look on the outside, prunes may have a secret superpower: They’re often touted as a natural constipation remedy thanks to their supposed laxative properties. Whole, sliced, or turned into juice, these dried plums are purported to help you poop—and that’s no small thing, as anyone who’s struggled to go on the regular can attest to, Amy Burkhart, MD, RD, a physician and registered dietitian who specializes in gut health, tells SELF. Depending on the severity of the case, constipation can cause bloating, discomfort, and even all-out pain—not exactly a recipe for a fun time.

But not all traditional home remedies actually work. So when it comes to prunes, is there any legit science to the persistent belief that they can help you drop a big one when all other methods fail? And if so, how many prunes a day should you eat for best results? Should you shovel down handfuls or is this a case where more does not always equal better? We pruned (sorry) the available scientific literature and consulted GI experts to find out.

How do prunes affect your gut, anyway?

Turns out, everything you’ve been told is true: Prunes really do help flush out your GI system, Lisa Ganjhu, DO, a gastroenterologist at NYU Langone Health, tells SELF. Because of their very makeup, prunes “stimulate your bowels,” she says. (Read: get things moving). In fact, research suggests that they’re even more effective than the well-known fiber supplement psyllium at, ahem, spurring an evacuation. How? It all comes down to three specific characteristics that not all fruits have, Dr. Burkhart explains. Let’s dig into each in a little more detail.

Often, people develop constipation because they’re not eating enough fiber, so it’s no real surprise that elevating your intake of that specific kind of carb can help treat the issue. And prunes really deliver in that regard. “[They’re] packed with fiber,” Dr. Ganjhu says. For instance, just one quarter cup of prunes contains around three grams, according to the USDA. This is important for toilet time, since fiber can help soften and bulk up your stool, speeding up its progress through your digestive tract.

Fiber-packed as prunes are, that isn’t “the only reason that they are good for treating constipation,” Dr. Burkhart says. Sorbitol—a sugar alcohol that is commonly added to candy and chewing gum to enhance their flavor and is also naturally found in some fruits and vegetables—is another. Besides imbuing prunes with their characteristic sweetness, sorbitol draws water into the digestive tract to give a natural laxative effect, which also “helps with making the stool softer and easier to pass,” Dr. Burkhart explains.

Compared to most other types of fruit, prunes are especially rich in phenolic compounds—antioxidants that may enhance the laxative effects of fiber and sorbitol.

What’s more, all three of these components—fiber, sorbitol, and phenols—may also help fight constipation by boosting your gut health (for example, enhancing the bacterial diversity in your gut). When they are broken down in your body, that process generates beneficial compounds known as short-chain fatty acids. This can “help balance the microbiome, which also then lowers your risk of constipation,” Dr. Burkhart explains.

Are prunes the only fruit that can help you poop, or do others have this effect too?

While prunes have a special triple-whammy of factors that make them effective at treating constipation, that doesn’t mean they’re your only option. In fact, “any dried fruit which is high-sugar and high-fiber is going to help as well,” Dr. Ganjhu says—figs, dates, apricots, and raisins, for example. “Any fruit in general, honestly,” Dr. Ganjhu adds. Some types of fresh fruit even contain a significant amount of sorbitol, including apples, pears, peaches, plums, and cherries. Finally, there’s always fruit juices like prune juice and apple juice. While these lack fiber since the juicing process removes most of it, they still retain the other essential constipation-fighting components (like sorbitol), so they’re also effective at helping clear backlogs.

Just keep in mind that these options might not work for everyone. Per Dr. Burkhart, people who follow a low-FODMAP diet—like those who have IBS or other stomach problems—might need to avoid eating foods high in sorbitol due to the potential for digestive upset. It can “cause GI issues—gas, bloating, sometimes diarrhea,” she says. In that case, fruit types that are high in fiber but lower in sorbitol would be better, like kiwi or raspberries.

How many prunes a day should you eat for best results?

Two words: Go slow. If you eat too many prunes at once and overwhelm your gut with fiber, “you’re definitely going to cause some distress,” Dr. Ganjhu says (namely, “a lot of bloating and diarrhea.”) It’s important to find a balance—eating enough prunes to have an effect on your constipation but not so many that the pendulum swings too far in the other direction.

“In general, you want to have about 25 to 30 grams of fiber [a day] in order to have a good bowel movement,” Dr. Ganjhu says. No, you don’t want all (or even most) of that to come from prunes—that’d be “too much sugar,” she explains—but they could help you reach your target number. So how many to shoot for? Typically, a few prunes should be enough for you to see a change. Try starting out with two or three (or half a cup to a cup of juice), according to Dr. Ganjhu, though you’re okay to have up to five if your initial dose isn’t cutting it. Since one eight-gram prune contains just over a half a gram of fiber, that’d shake out to around three grams in total. Of course, everyone is different, so your tolerance might be lower or higher, but that ballpark will work for most people.

If you do decide to level up, make it gradual. Increase your serving size by one prune at a time until your symptoms start to abate—when you “start having looser stools, more comfortable bowel movements, feeling more regular,” Dr. Burkhart says. Leave two or three days between each increase so your body has time to adjust. You’ll want to follow the same protocol with prune juice, increasing by half a cup each time.

What’s the best way to eat your prunes to relieve constipation?

In addition to starting slow, there’s a couple of other measures you can take to make sure you have the best experience possible.

First, eat your prunes early in the day. Like we mentioned, suddenly introducing a bunch of fiber into your diet can cause digestive discomfort, so this way, any negative effects won’t affect your sleep, according to Dr. Burkhart. “I don’t want you kept up because you have gas and bloating because you ate prunes at 9:00 p.m.,” she says. While the length of time it will take you to, ahem, feel the impact can vary from person to person—after all, “everyone’s GI tract speed is different,” Dr. Ganjhu says—it will typically range from a few hours to a day or so, according to Mercy Health. And if you keep it up? You might see more, um, regular benefits too. In a 2022 study published in The American Journal of Gastroenterology, researchers found that 84 people suffering from chronic constipation experienced a noticeable improvement in the consistency and frequency of their stool within three weeks of starting to drink prune juice every day.

And remember to drink plenty of water so your stool is soft enough to pass easily. “If you don’t increase your water intake along with the fiber, you’re going to worsen your constipation,” Dr. Burkhart says. Have your daily prune dose along with a glass of H2O to make sure this doesn’t happen.

Finally, don’t think that pounding prunes can make up for skimping on other lifestyle best practices if you’re looking for a natural constipation remedy. The dried fruits are “just one piece” of the puzzle,” Dr. Burkhart says. Getting enough exercise, sleeping well, managing stress effectively, and eating a balanced diet can all help improve your symptoms too.

Related:

• 10 High-Fiber Fruits to Make Breakfasts, Lunches, and Standalone Snacks More Filling
• What Really Happens If You Eat Grapefruit With Your Meds?
• Wait, Should I Have Been Washing My Bananas This Entire Time?!

Get more of SELF’s great food coverage delivered right to your inbox.