Constipation is one of those things nobody wants to talk about, but a lot of people quietly deal with. Many of the foods that cause constipation are everyday staples that most people would never suspect. Once you know what they are, small changes can start to make a noticeable difference.
If you have fewer than three bowel movements a week, or you regularly feel bloated, heavy, and backed up, diet is usually one of the first places worth looking.
8 Foods That Tend to Make Constipation Worse
- Dairy
For some people, dairy is a meaningful driver of constipation, particularly cow’s milk. A double-blind clinical trial published in the New England Journal of Medicine found that among young children with chronic constipation that had not responded to laxatives, 68% experienced relief when cow’s milk was removed from their diet. (1) Research in children has been the most consistent on this point, though adults who are sensitive to dairy proteins or lactose may notice a similar pattern.
If you consume a lot of dairy and deal with ongoing constipation, it may be worth reducing it for a couple of weeks to see whether that helps.
- Processed Grains
White bread, pasta, pastries, and most packaged cereals go through processing that strips out the fiber naturally found in whole grains. Fiber adds bulk to stool and keeps things moving through the digestive tract. Without it, the digestive system slows down.
A 2024 systematic review and meta-analysis from King’s College London found that dietary fiber was among the most consistently effective interventions for improving stool output and bowel movement frequency in adults with chronic constipation. (2) Swapping even one or two servings of processed grains for whole grain versions each day is a practical starting point.
- Unripe Bananas
Ripe and unripe bananas behave very differently in the gut. Green, underripe bananas are high in resistant starch, a type of carbohydrate the body struggles to digest. In some people, particularly those already prone to constipation, large amounts of green bananas may contribute to firmer stools. Ripe bananas work the other way, containing natural prebiotic fiber that may support healthy digestion and more regular bowel movements.
The fix is simple: let them yellow before eating.
- Coffee (When You Are Already Dehydrated)
Coffee often stimulates bowel movements, but in some people excessive caffeine intake combined with inadequate fluid intake may contribute to dehydration, which can worsen constipation. (3)
Low liquid intake is consistently linked to higher constipation rates, particularly among women. Staying well-hydrated throughout the day matters more than most people realize, and caffeine intake is worth factoring in when tracking how much fluid you are actually getting.
- Refined Sugar
Foods high in refined sugar, like pastries, candy, and sweetened drinks, tend to be low in fiber and high in fat. That combination gives the digestive system very little to work with. Sugar-heavy foods also tend to crowd out the fiber-rich foods that keep digestion moving, which compounds the problem over time.
- Ultra-Processed Foods
This category covers a lot of ground: fast food, packaged snacks, frozen meals, processed lunch meats, flavored crackers, and similar products. What they have in common is that they tend to be high in sodium, saturated fat, and additives, while being low in fiber and nutrients.
A 2024 NHANES-based study published in Clinical Gastroenterology and Hepatology found that among more than 12,000 U.S. adults, higher ultra-processed food intake was independently associated with significantly greater odds of constipation, even after adjusting for overall diet quality. (4) The researchers also found that simply substituting some ultra-processed food with minimally processed alternatives was associated with meaningfully lower constipation risk.
The high sodium in many of these foods adds another layer. Excess sodium draws water out of the intestines, which can lead to harder, drier stool that is more difficult to pass.
If constipation is an ongoing issue, looking at how many meals or snacks are coming from this category is a reasonable place to start. Some people also find it helpful to explore a gentle bowel support formula designed to help things move more comfortably.
- White Rice
White rice has had its bran and germ removed during processing, which is exactly where most of the fiber is. What is left digests quickly but contributes almost nothing in terms of digestive bulk. Brown rice, farro, quinoa, or barley are easy substitutes that bring meaningful fiber back to the plate.
- Alcohol
Alcohol may contribute to constipation through dehydration and changes in digestive function, particularly when consumed in larger amounts. It suppresses vasopressin, a hormone that helps the body retain fluid, which can increase urination and fluid loss. When the body is dehydrated, the colon pulls more water from waste to compensate, which can result in harder, drier stool.
If alcohol is a regular part of your routine and constipation is ongoing, staying well-hydrated when drinking is a reasonable first step.
The Best Juice and Fruit for Constipation Relief
If you want a natural, food-based option for occasional relief, two options have the most clinical support right now.
Prune juice is the longest-studied choice. A randomized controlled trial published in the American Journal of Gastroenterology found that regular prune juice intake significantly softened stool consistency and reduced hard, lumpy stools in adults with chronic constipation, without causing diarrhea or adverse effects. (5) Prune juice works through three main components: sorbitol, which draws water into the colon; pectin, a soluble fiber; and polyphenols that may support gut motility. A modest amount, roughly 4 to 8 ounces daily, is generally what research has used.
Kiwifruit has emerged as one of the most well-supported whole-food options in recent gastroenterology research. A 2023 international multicenter RCT published in the American Journal of Gastroenterology found that eating two green kiwifruits daily produced clinically meaningful improvements in bowel movement frequency and was better tolerated than psyllium fiber in people with functional constipation. [6] The 2024 Van Der Schoot meta-analysis also identified kiwifruit as one of the most consistent whole-food interventions across the constipation literature. (2)
Both are easy to find, inexpensive, and well-tolerated at moderate amounts. They work through different mechanisms, so some people find one suits them better than the other.
If you are looking for additional digestive support beyond diet, it may be worth exploring a targeted bowel support option designed to help with comfort and regularity.
More Fiber, More Movement
Most Americans still fall well short of recommended fiber intake. (3) For adults, the NIDDK recommends between 22 and 34 grams per day depending on age and sex, and most people are not close to that range.
Getting more fiber does not have to mean a dramatic diet overhaul. Leafy greens, lentils, apples, pears, oats, and berries are all practical, easy-to-find options that add up quickly. Drinking enough water alongside fiber-rich foods matters too, since fiber works best when it has fluid to absorb.
Small Changes That Add Up
Constipation rarely has one single cause. More often it is a combination of a few habits converging over time. Reducing the foods most likely to slow things down, getting more fiber from whole food sources, staying hydrated, and being thoughtful about alcohol and caffeine intake are adjustments that tend to work better together than any one of them would alone.
Starting with one or two changes at a time is usually more sustainable than trying to overhaul everything at once.
Learn about your options here.
Sources
[1] Iacono G, et al. Intolerance of cow’s milk and chronic constipation in children. New England Journal of Medicine. 1998;339(16):1100-4. https://pubmed.ncbi.nlm.nih.gov/9770556/
[2] Van Der Schoot A, Katsirma Z, Whelan K, Dimidi E. Systematic review and meta-analysis: foods, drinks and diets and their effect on chronic constipation in adults. Alimentary Pharmacology and Therapeutics. 2024;59(2):157-174. https://pubmed.ncbi.nlm.nih.gov/37905980/
[3] Markland AD, et al. Association of low dietary intake of fiber and liquids with constipation: evidence from NHANES. American Journal of Gastroenterology. 2013. https://pmc.ncbi.nlm.nih.gov/articles/PMC3786707/
[4] Lo CH, et al. Association of ultra-processed food and unprocessed or minimally processed food consumption with bowel habits among U.S. adults. Clinical Gastroenterology and Hepatology. 2024;22(11):2309-2318. https://pubmed.ncbi.nlm.nih.gov/38759823/
[5] Koyama T, et al. Prune juice containing sorbitol, pectin, and polyphenol ameliorates subjective complaints and hard feces while normalizing stool in chronic constipation. American Journal of Gastroenterology. 2022;117:1714-1717. https://journals.lww.com/ajg/_layouts/15/oaks.journals/downloadpdf.aspx?an=00000434-202210000-00032
[6] Gearry R, et al. Consumption of 2 green kiwifruits daily improves constipation and abdominal comfort: results of an international multicenter randomized controlled trial. American Journal of Gastroenterology. 2023;118(6):1058-1068. https://pubmed.ncbi.nlm.nih.gov/36537785/