What Foods Are Good to Eat for Constipation?

Fiber-rich whole foods, certain fruits, and a handful of specific dietary additions can meaningfully relieve constipation, often without medication. Prunes, kiwifruit, flaxseed, whole grains, legumes, and fermented dairy all have clinical evidence behind them, though they work through different mechanisms and suit different people. The details matter more than any generic “eat more fiber” advice, because the type of fiber, the foods that carry it, and what you drink alongside it all change how well things move.

Prunes and Prune Juice

Prunes are probably the most culturally familiar constipation remedy, and the science backs their reputation. They work through a combination of sorbitol (a sugar alcohol that draws water into the intestine), pectin (a soluble fiber), and polyphenols, all of which contribute to softer, easier-to-pass stools.¹ That triple action is part of why prunes tend to outperform supplements that deliver only one type of fiber. Prune juice works too, though whole prunes deliver more fiber per serving.

Research on fruits and constipation suggests that prunes increase fecal weight in humans, which is a straightforward marker of improved bowel function.² Interestingly, prunes don’t appear to speed up gut transit time the way some other fruits do. Their benefit is more about softening and bulking stool than about making the colon contract faster. A typical effective dose in studies is around 100 grams of prunes per day, which is roughly 10 to 12 prunes.

Kiwifruit

Kiwifruit has emerged as one of the better-studied foods for constipation relief, and the results are consistently positive. A large multicenter trial found that eating two green kiwifruits daily improved constipation symptoms, and the mechanism is well understood: kiwifruit fiber has an unusual ability to swell and retain water in the small bowel and colon, increasing total colonic volume.³ That extra water softens stool and makes passage easier.

Gold kiwifruit appears to work similarly. In a trial comparing gold kiwifruit to psyllium (a well-established fiber supplement), both improved constipation scores and softened stool. But kiwifruit had an edge on straining: people eating two gold kiwifruits daily strained less during bowel movements, while psyllium didn’t improve straining scores at all.⁴ For people whose main complaint is difficulty and discomfort during bowel movements rather than infrequency, that distinction matters.

Kiwifruit also shifts the gut microbiome in ways that may have longer-term digestive benefits, encouraging growth of bacterial species associated with healthy gut function.² Two kiwifruits per day is the dose used in most positive trials.

Psyllium Husk

Psyllium is the most studied fiber supplement for constipation, and it’s approved as an over-the-counter treatment for occasional constipation. It forms a gel in the gut that resists fermentation and holds onto water all the way through the large intestine. In a study of 170 people with chronic constipation and hard stools, psyllium (about 5 grams twice daily) raised stool water content to normal levels within three days, and that improvement held for the full two-week treatment period.⁵

What makes psyllium unusual is its “normalizing” effect on stool. It softens hard stool in people who are constipated, but it also firms up loose stool in people with diarrhea.⁶ This bidirectional quality makes it a safe first choice when you’re not sure what’s going on with your digestion. Its high water-holding capacity and gel-forming ability are the properties that drive these benefits.⁷

A trial directly comparing psyllium to a mixed soluble/insoluble fiber supplement found both were equally effective: about three-quarters of participants in each group responded, with bowel movements increasing from roughly 1.5 per week to about 3.5 per week.⁸ Both also improved stool consistency and reduced straining. If you’re choosing a fiber supplement and have no strong preference, psyllium is the one with the deepest evidence base.

Flaxseed

Ground flaxseed is an underappreciated option. Like psyllium, flaxseed contains mucilage, a gel-forming fiber that draws water into the stool. In a study of older adults with constipation, flaxseed treatment cut constipation severity scores roughly in half and nearly doubled weekly bowel movement frequency. By the end of the intervention, about 87% of participants had normal stool consistency, and the overall effectiveness rate was close to 90%.⁹

Ground flaxseed is preferable to whole because the seeds need to be broken open for your body to access the mucilage and the fiber inside. A tablespoon or two stirred into yogurt, oatmeal, or a smoothie is a common approach. Flaxseed also provides omega-3 fatty acids and lignans, so it pulls double duty nutritionally, though those benefits are separate from the constipation relief.

Whole Grains and Wheat Bran

Wheat bran is a traditional recommendation for constipation, but the particle size matters more than people realize. Coarse wheat bran increases stool water content, softening stool in the way you’d want. Finely ground wheat bran, however, actually decreases stool water content and can harden stool, making constipation worse.¹⁰ This is a genuine gotcha: if you’re eating a finely milled “high-fiber” cereal and wondering why it isn’t helping, this might be why.

Other whole grains like oats, barley, and brown rice also contribute fiber, though they haven’t been studied as isolated interventions the way psyllium or prunes have. Their value is more as part of a broadly fiber-rich diet. If you’re currently eating mostly refined grains (white bread, white rice, regular pasta), switching to whole-grain versions is one of the simplest dietary changes you can make for bowel regularity.

Legumes

Beans, lentils, and chickpeas are among the most fiber-dense everyday foods, and they bring a form of fiber that most other foods don’t deliver much of: resistant starch. Resistant starch passes through the small intestine undigested and reaches the colon, where gut bacteria ferment it into short-chain fatty acids. These fatty acids support the health of the colon lining and promote beneficial bacterial growth.¹¹ Animal research confirms that processed legumes increase fecal bulk and short-chain fatty acid production.¹²

The downside is well known: legumes can cause gas, especially if you’re not used to eating them. The standard advice to increase legume intake gradually over a couple of weeks is genuinely useful here. Starting with smaller lentils or split peas, which tend to be easier to digest than larger beans, can also help.

Fermented Dairy

Yogurt and fermented milk products are a different angle on constipation. Rather than adding bulk or water to stool, they work through the gut microbiome. In a trial of women with constipation, fermented milk containing a specific probiotic strain (Bifidobacterium lactis) increased stool frequency, improved stool consistency, and reduced difficulty with defecation compared to regular milk over two weeks.¹³

Not every yogurt on the shelf will produce this effect. The strain of probiotic matters, and most commercial yogurts contain only the starter cultures used for fermentation rather than clinically tested probiotic strains. If you’re trying yogurt specifically for constipation, look for products that list named probiotic strains like B. lactis on the label, not just “live active cultures.”

Coffee

Many people notice that coffee sends them to the bathroom, and this isn’t just placebo. Research using direct measurement of colon activity found that coffee increased movement in the rectosigmoid (the final section of the colon) within four minutes of drinking it, and the effect lasted at least 30 minutes. This happened with both regular and decaffeinated coffee, meaning caffeine alone isn’t the full explanation.¹⁴

There’s a catch, though: not everyone responds. In that study, about 60% of participants showed increased colon motility after coffee, while about 40% didn’t respond at all. If coffee doesn’t already make you feel the urge, it probably won’t start working as a constipation remedy. And coffee’s dehydrating properties at high volumes could theoretically offset some of its benefit, so keeping total fluid intake adequate is still important.

Olive Oil

Olive oil, particularly extra virgin olive oil, has a long folk-medicine history as a constipation remedy, and there’s now trial evidence to support it. In a double-blind trial, people consuming extra virgin olive oil daily for four weeks saw constipation symptom scores drop substantially more than those consuming refined olive oil. Stool consistency also improved more in the extra virgin group by the second week and continued improving through week four.¹⁵ The polyphenols and oleic acid in extra virgin oil appear to be the active components, since refined oil (which has fewer of these compounds) was less effective.

A tablespoon or two of extra virgin olive oil in the morning, either straight or mixed into food, is a common approach. It’s easy to incorporate through salad dressings or drizzled over vegetables, so it doesn’t require any special effort if you already cook with it.

Why Water Matters More Than You Think

Fiber only works well when there’s enough water for it to absorb. A study specifically testing this interaction found that while a high-fiber diet alone improved stool frequency and reduced laxative use, the effect was significantly stronger in people who also increased their fluid intake to about 1.5 to 2 liters per day. Both stool frequency improvements and laxative reductions were greater in the higher-fluid group.¹⁶

This matters practically because many people add fiber to their diet (through supplements or food changes) without adjusting their fluid intake. Gel-forming fibers like psyllium and flaxseed pull water into the stool to soften it, so if you’re not drinking enough, adding fiber can actually make things feel worse. Magnesium-rich mineral water may offer a small additional advantage, since magnesium itself draws water into the intestinal lumen through osmotic effects.¹⁷

Foods That Make Constipation Worse

Knowing what to eat is only half the picture. A large study of U.S. adults found that people whose diets were highest in ultra-processed foods had roughly double the odds of constipation compared to those who ate the least. Conversely, greater consumption of minimally processed or unprocessed foods was associated with significantly lower odds of constipation.¹⁸ Ultra-processed foods tend to be low in fiber, high in refined carbohydrates, and often contain emulsifiers and additives that may disrupt gut motility.

Common culprits include fast food, packaged snacks, processed meats, sugary cereals, and frozen ready meals. You don’t need to eliminate these entirely, but if your diet is heavily tilted toward them, adding prunes or psyllium on top may not be enough to compensate. The overall dietary pattern matters.

When Fiber Backfires

Fiber is the default recommendation for constipation, but it can cause problems of its own. Even when used carefully, fiber can worsen bloating, gas, and in some cases constipation itself.¹⁹ A study testing high-fiber diets found that diets higher in protein alongside the fiber increased bloating risk compared to diets higher in carbohydrates, suggesting that how you combine fiber with other foods may influence whether you get uncomfortable side effects.²⁰

The practical takeaway is that ramping up slowly matters. If you go from 10 grams of daily fiber to 30 grams overnight, you’ll almost certainly feel worse before you feel better. Increasing by about 5 grams every few days, with adequate water, gives the gut microbiome time to adjust. If bloating persists despite gradual increases, gel-forming fibers like psyllium tend to produce less gas than fermentable fibers like inulin or wheat bran, because the gel structure resists bacterial breakdown.

Constipation During Pregnancy

Pregnancy-related constipation is common, driven by hormonal changes that slow gut motility and by the physical pressure of a growing uterus. The evidence supports fiber as a first-line approach: increasing fiber through diet or supplements is the standard initial recommendation.²¹ A Cochrane review of trials in pregnant women found that fiber supplements (bran or wheat fiber) increased defecation frequency and led to softer stools.²²

The foods discussed throughout this article are generally safe in pregnancy. Prunes, kiwifruit, flaxseed, oats, and legumes are all reasonable options. The one area where pregnant women should be more cautious is with any supplement (including concentrated fiber products), where checking with a healthcare provider is worth the minor inconvenience. Staying well hydrated is especially important during pregnancy, since blood volume expansion already increases fluid needs.

Putting a Plate Together

In practice, the most effective dietary approach to constipation isn’t a single magic food but a pattern. A useful daily framework might include two kiwifruits or a serving of prunes, a portion of legumes (lentils in soup, chickpeas in a salad), whole grains rather than refined, a tablespoon of ground flaxseed mixed into breakfast, and a drizzle of extra virgin olive oil at dinner. Add a cup or two of coffee if you’re among the majority who respond to it, a serving of probiotic-containing yogurt, and at least 1.5 liters of fluid. That covers multiple mechanisms at once: gel-forming fiber, osmotic sugar alcohols, water-retaining fruit fiber, resistant starch, healthy fats, and microbiome support.

Nobody eats this perfectly every day, and you don’t have to. The point is that constipation-friendly eating isn’t about choking down bran cereal. It’s a collection of genuinely enjoyable foods, most of which belong in a Mediterranean-style diet anyway, working through enough different pathways that your gut gets the message from multiple directions at once.