Are Dates or Prunes Better for Constipation?

Prunes have considerably stronger clinical evidence for relieving constipation than dates do. Multiple randomized trials in humans have tested prunes head-to-head against standard fiber supplements and shown meaningful improvements in stool frequency and consistency, while dates have been studied mostly in animal models and lab settings. That does not mean dates are useless for keeping things moving, but if you are choosing between the two specifically to address constipation, the research tilts firmly in favor of prunes. The reasons come down to a combination of what each fruit contains and how well each has actually been tested.

What the Trials Say About Prunes

Prunes are one of the few whole foods that have been put through proper clinical trials for constipation relief, and the results are consistently positive. In one well-known randomized trial, people with chronic constipation who ate about 100 grams of prunes per day for three weeks had significantly more complete spontaneous bowel movements per week than those taking psyllium, a widely used fiber supplement: roughly 3.5 versus 2.8 per week. Their stool consistency also improved, scoring softer on the Bristol stool scale.¹ A separate trial confirmed that prunes beat psyllium on complete spontaneous bowel movements and stool consistency scores.²

Dose matters. A trial testing 80 grams and 120 grams of prunes per day found that both amounts significantly increased stool weight and frequency compared to a control diet. The 80-gram group averaged about 6.8 bowel movements per week, versus 5.4 in the control group.³ That is a noticeable difference for anyone who struggles with regularity. Even prune juice, not just the whole dried fruit, has shown benefits in a placebo-controlled trial, softening hard stools and easing subjective complaints in people with chronic constipation.⁴

A three-way comparison trial pitted prunes against green kiwifruit and psyllium in people with chronic constipation. All three treatments increased weekly bowel movement frequency. Prunes significantly improved stool consistency and reduced straining. Kiwifruit performed similarly and had the added benefit of reducing bloating, which prunes did not.⁵ The takeaway: prunes work, and they work at least as well as the fiber supplement most doctors recommend first.

What the Research Says About Dates

Dates are a different story. They are a genuinely fiber-rich fruit, and people across the Middle East and North Africa have used them for digestive comfort for centuries. But when you look for the kind of controlled human trials that exist for prunes, they are essentially absent. The strongest direct evidence for dates and constipation comes from animal research. An in vivo study using rats found that an aqueous extract of date pulp significantly and dose-dependently increased gastrointestinal transit activity, supporting the traditional use of dates as a laxative.⁶ That is promising, but what happens in a rat’s gut does not always translate cleanly to human outcomes.

Dates do have a solid nutritional profile for gut health. Analysis of common date varieties shows total dietary fiber content of roughly 14 to 18 percent on a dry-weight basis, with insoluble fiber making up the majority of that.⁷ Insoluble fiber adds bulk to stool and can speed transit through the colon. So there is a plausible mechanism. But plausible mechanism and proven clinical effect are two different things, and for dates the clinical proof simply has not been produced yet.

Why Prunes Work So Well

Prunes owe their laxative reputation to more than just fiber. They contain a combination of sorbitol, pectin, and polyphenols that work together in ways plain fiber alone does not. Sorbitol is a sugar alcohol that your small intestine absorbs poorly. When it reaches the colon largely intact, it pulls water into the bowel through osmosis, softening the stool. Pectin, a soluble fiber, adds gel-like bulk and feeds beneficial gut bacteria. Polyphenols appear to stimulate colonic motility on their own. A trial on prune juice concluded that the constipation relief was likely driven by this combination of sorbitol, pectin, and polyphenols acting together rather than any single ingredient.⁴

The fiber in prunes includes hemicellulose, pectin, and cellulose. A clinical review noted that this profile promotes an increase in stool weight without substantially raising its water content, meaning prunes primarily work by increasing stool volume.⁸ That volume, combined with the osmotic pull of sorbitol, creates a stool that is both bulkier and softer. Dates have fiber and some natural sugars, but they contain far less sorbitol, which is the ingredient most responsible for prunes’ edge.

Gut Microbiome Effects of Dates

Where dates get more interesting is in their prebiotic potential. In vitro fermentation studies show that whole dates significantly increased the growth of bifidobacteria and bacteroides, two groups of bacteria associated with healthy gut function.⁹ More recent animal research found that polysaccharides from date byproducts lowered the ratio of Firmicutes to Bacteroidetes in the gut, promoted bacteria that produce short-chain fatty acids, and suppressed opportunistic pathogens.¹⁰

Short-chain fatty acids produced by gut bacteria nourish the cells lining your colon, support the intestinal mucus barrier, and help regulate motility. So dates might support regular bowel habits indirectly, by cultivating a healthier microbial environment rather than acting as an immediate laxative. If you are not in acute constipation but want to support long-term digestive health, adding dates to your diet has some rationale behind it. Just do not expect the same quick relief you would get from prunes.

Tolerability and Side Effects

Prunes work well, but they can be gassy. A clinical trial found that flatulence was significantly more common during prune consumption.³ This is not surprising given the sorbitol content. Your colon bacteria ferment sorbitol, and gas is one of the byproducts. Most people can adapt within a week or two, especially if they start with a smaller serving and work up. But for some, the bloating and gas are uncomfortable enough to be a deal-breaker.

Both prunes and dates are high in fructose and contain compounds categorized as FODMAPs, short-chain carbohydrates that are poorly absorbed in the small intestine. People with fructose intolerance or irritable bowel syndrome may experience bloating, abdominal pain, or diarrhea from either fruit.¹¹ If you already know you react badly to high-FODMAP foods, both fruits deserve caution. Starting with a small amount and seeing how your gut responds is the sensible approach. Dates may be slightly easier to tolerate in small quantities because they lack the high sorbitol punch that makes prunes so effective but also so gas-producing.

Calorie content is worth mentioning. A 100-gram serving of prunes (the dose used in the major constipation trials) runs about 240 calories, roughly the same as 100 grams of dates. These are calorie-dense fruits. If you are eating 100 grams daily for weeks, that adds up. For most people this is manageable, but it is something to factor in if you are watching your intake closely.

Whole Fruit Versus Juice

Prune juice is popular partly because some people find it more palatable than eating a handful of sticky dried fruit. The randomized trial on prune juice found it effective at softening hard stools and reducing subjective constipation complaints, with the researchers attributing the benefit to the combination of sorbitol, pectin, and polyphenols present in the juice.⁴ However, juice loses much of the insoluble fiber that whole prunes contain. The insoluble fiber is what adds bulk, while the juice mostly delivers the osmotic and chemical effects. For maximum benefit, whole prunes are likely better, but juice is a reasonable alternative if the texture of dried prunes is unappealing.

Date syrup and date paste are common in cooking, but there is no clinical evidence that these processed forms retain the fiber content or gut-stimulating effects seen in whole dates or date pulp extract. If you are eating dates for digestive purposes, stick with whole pitted dates rather than concentrated syrups.

How Prunes Compare to Other Whole-Food Options

A 2023 meta-analysis that pooled evidence across multiple foods and drinks for chronic constipation in adults found that fruits overall produced higher stool frequency than psyllium, with kiwifruit showing a particular edge. Interestingly, when prunes were analyzed separately against psyllium in that meta-analysis, the difference was not statistically significant, even though individual trials had shown prunes outperforming psyllium.¹² This likely reflects the smaller number of prune-specific trials available for pooling, rather than a genuine lack of effect. Individual trials consistently show prunes working, but the overall evidence base is still relatively small.

The three-way comparison trial mentioned earlier found that kiwifruit and prunes performed similarly for stool frequency and consistency, but patients reported less bloating with kiwifruit and were less likely to be dissatisfied at the end of treatment.⁵ So if prunes cause too much gas for you, kiwifruit is worth trying as an alternative whole-food remedy with evidence behind it. Dates, by contrast, have not been included in any of these head-to-head human trials.

Practical Guidance for Choosing

If your primary goal is to relieve constipation that is already happening, prunes are the evidence-based choice. A reasonable starting dose is about 50 grams per day (roughly five or six prunes), increasing to 80 or 100 grams if needed and tolerated. Most of the trial evidence clusters around that 80-to-100-gram range. Give it at least a week or two before deciding whether it is helping. Eating them with a glass of water helps the fiber do its job.

If you prefer dates, or you already eat them regularly and want to know whether they are helping your digestion, they probably do contribute some benefit through their fiber content and prebiotic effects. But the honest answer is that nobody has run the kind of trial that would tell us how well dates work for constipation in humans compared to a placebo or another treatment. You would be relying on fiber content and traditional use rather than clinical proof.

There is no reason you cannot eat both. Prunes and dates have different flavor profiles and nutrient compositions, and combining them in a morning snack or blended into oatmeal gives you the sorbitol-driven laxative push of prunes plus the prebiotic fiber of dates. A mixed-fruit porridge containing prunes alongside other high-fiber ingredients was effective and well-liked by geriatric patients in one study, and reduced their need for pharmaceutical laxatives.¹³

Dates in Pregnancy

Constipation is extremely common during pregnancy, and many pregnant women look for food-based remedies to avoid medication. Dates have attracted particular research interest in pregnancy, though mainly for labor outcomes rather than constipation. One trial found that pregnant women who consumed dates had a significantly shorter latent phase of labor and were less likely to need oxytocin to stimulate contractions.¹⁴ That is not a constipation finding, but it means dates are generally considered safe during pregnancy and are being actively studied in that population. If you are pregnant and constipated, prunes remain the better-supported choice for the constipation itself, while dates may offer their own separate benefits later in the pregnancy.

When to See a Doctor Instead

Dietary remedies like prunes and dates are appropriate for occasional constipation or mild chronic constipation. They are not a substitute for medical evaluation when constipation is severe, sudden in onset, accompanied by blood in the stool, or associated with unexplained weight loss. Constipation that does not respond to increased fiber, fluids, and physical activity within a few weeks deserves professional attention. Chronic constipation can sometimes signal an underlying condition that no amount of dried fruit will fix, from thyroid problems to pelvic floor dysfunction. Prunes and dates sit firmly in the “reasonable first thing to try” category, not the “this will solve everything” category.

1
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