Constipation is a common problem that’s generally defined as having less than three bowel movements per week ().
In fact, as many as 27% of adults experience it and its accompanying symptoms, such as bloating and gas. The older or more physically inactive you get, the more likely you are to experience it (, ).
Some foods can help relieve or reduce the risk of constipation, while others can make it worse.
This article examines 8 foods that can cause constipation.
1. Unripe Bananas
While ripe bananas can help prevent constipation, unripe bananas tend to have the opposite effect.
That's because unripe bananas contain more resistant starch, a compound that is harder for the body to digest ().
During the ripening process, resistant starch is converted into natural sugars, which are much easier to digest.
Unripe bananas also contain higher amounts of tannins, a compound thought to reduce the speed at which foods pass through the gut ().
Most people tend to eat bananas well before they reach their prime ripeness. However, if you want to relieve or avoid constipation, try eating ripe bananas instead of unripe ones.
Ripe bananas are completely yellow and show some signs of brown spotting. They should be very easy to peel.
Summary: Unripe bananas contain more tannins and resistant starch than ripe bananas. This makes them more likely to cause constipation.
Alcohol is frequently mentioned as a likely cause of constipation.
That's because if you drink alcohol in large amounts, it can increase the amount of fluids lost through your urine, causing dehydration.
Poor hydration, either due to not drinking enough water or losing too much of it through urine, is often linked to an increased risk of constipation (, ).
Unfortunately, no studies could be found on the direct link between alcohol consumption and constipation. Moreover, some people report experiencing diarrhea, rather than constipation, after a night out drinking ().
It is possible that effects vary from person to person. Those wanting to counteract the potentially dehydrating and constipating effects of alcohol should try to offset each serving of alcohol with a glass of water or another non-alcoholic beverage.
Summary: Alcohol, especially when consumed in large amounts, can have a dehydrating effect that may increase the risk of constipation. Effects may vary from person to person, and more studies are needed before strong conclusions can be made.
3. Gluten-Containing Foods
Gluten is a protein found in grains like wheat, barley, rye, spelt, kamut and triticale. Some people may experience constipation when they eat foods that contain gluten ().
Also, some people are intolerant to gluten. This is a condition known as celiac disease.
When someone with celiac disease consumes gluten, their immune system attacks their gut, severely harming it. For this reason, individuals with this disease must follow a gluten-free diet ().
In most countries, an estimated 0.5–1% of people have celiac disease, but many may not be aware of it. Chronic constipation is one of the common symptoms. Luckily, avoiding gluten can help relieve and heal the gut (, , ).
Non-celiac gluten sensitivity (NCGS) and irritable bowel syndrome (IBS) are two other instances in which a person's gut may react to gluten. Individuals with these medical conditions aren't intolerant to gluten but appear to be sensitive to it.
Moreover, studies show that many people without these conditions may also experience constipation after consuming gluten (, ).
If you suspect gluten is causing your constipation, make sure to speak to your healthcare professional to rule out celiac disease before cutting gluten from your diet.
This is important, as gluten needs to be in your diet for the test for celiac disease to work properly. If you’ve ruled out celiac disease, you may want to experiment with consuming different levels of gluten to evaluate its effects on you.
Summary: Individuals with celiac disease, NCGS or IBS may be more likely to experience constipation as a result of consuming gluten.
4. Processed Grains
Processed grains and their products, such as white bread, white rice and white pasta, are less nutritious and may be more constipating than whole grains.
That's because the bran and germ parts of the grain are removed during processing. In particular, the bran contains fiber, a nutrient that adds bulk to stool and helps it move along.
Many studies have linked a higher fiber intake to a lower risk of constipation. In fact, a recent study reported a 1.8% lower likelihood of constipation for every additional gram of fiber consumed per day (, ).
Therefore, people experiencing constipation may benefit from gradually reducing their intake of processed grains and replacing them with whole grains.
Although extra fiber is beneficial for most people, some people experience the opposite effect. For them, extra fiber may worsen constipation, rather than relieve it (, ).
If you are constipated and already consuming a lot of fiber-rich whole grains, adding more fiber to your diet is unlikely to help. In some cases, it may even make the problem worse ().
If this is the case for you, try gradually reducing your daily intake of fiber to see if this provides some relief.
Summary: Processed grains and their products, such as white rice, white pasta and white bread, contain less fiber than whole grains, making them generally more constipating. On the other hand, some people find that consuming less fiber helps relieve constipation.
5. Milk and Dairy Products
Dairy appears to be another common cause of constipation, at least for some people.
Infants, toddlers and children appear particularly at risk, possibly due to a sensitivity to the proteins found cow's milk ().
A review of studies conducted over a 26-year period found that some children with chronic constipation experienced improvements when they stopped consuming cow’s milk ().
In a recent study, children aged 1–12 with chronic constipation drank cow's milk for a period of time. The cow's milk was then replaced by soy milk for a subsequent period of time.
Nine of the 13 children in the study experienced constipation relief when cow's milk was replaced by soy milk ().
There are many anecdotal reports of similar experiences in adults. However, little scientific support could be found, since most studies examining these effects are focused on children, not older populations.
It's worth noting that those who are lactose intolerant may experience diarrhea, rather than constipation, after consuming dairy.
Summary: Dairy products may cause constipation in some individuals. This effect is most common in those who are sensitive to the proteins found in cow's milk.
6. Red Meat
Red meat may worsen constipation for three main reasons.
First, it contains little fiber, which adds bulk to the stools and helps them move along.
Second, red meat may also indirectly reduce a person's total daily fiber intake by taking the place of higher-fiber options in the diet.
This is especially true if you fill up on a large portion of meat during a meal, reducing the amount of fiber-rich vegetables, legumes and whole grains you can eat in the same sitting.
This scenario would lead to an overall lower daily fiber intake, potentially increasing the risk of constipation ().
Furthermore, unlike other types of meat, such as poultry and fish, red meat generally contains higher amounts of fat, and high-fat foods take longer for the body to digest. In some cases, this may increase the likelihood of constipation even further ().
Those with constipation may benefit from replacing the red meat in their diet with protein- and fiber-rich alternatives such as beans, lentils and peas.
Summary: Red meat is generally high in fat and low in fiber, a nutrient combination that may increase the risk of constipation. If you let red meat replace fiber-rich foods in your diet, it can increase the risk even further.
7. Fried or Fast Foods
Eating large or frequent portions of fried or fast foods may also increase the risk of constipation.
That's because these foods tend to be high in fat and low in fiber, a combination that can slow digestion in the same way that red meat does ().
Fast-food snacks like chips, cookies, chocolate and ice cream may also replace more fiber-rich snack options, such as fruits and vegetables in a person's diet.
This can further increase the likelihood of constipation by reducing the total amount of fiber consumed per day ().
Interestingly, many people believe chocolate is one of the main causes of their constipation ().
Furthermore, fried and fast foods tend to contain large amounts of salt, which can lower the water content of stool, drying it up and making it harder to push through the body ().
This happens when you eat too much salt, as your body sucks up water from your intestines to help compensate for the extra salt in your bloodstream.
This is one way your body works to bring its salt concentration back to normal, but unfortunately, it can lead to constipation.
Summary: Fried and fast foods are low in fiber and high in fat and salt. These characteristics may slow digestion and increase the likelihood of constipation.
Persimmons are a popular fruit from Eastern Asia that may be constipating for some people.
Several varieties exist, but most can be categorized as either sweet or astringent.
In particular, astringent persimmons contain a large amount of tannins, a compound thought to reduce gut secretions and contractions, slowing down bowel movements ().
For this reason, people experiencing constipation should avoid consuming too many persimmons, especially astringent varieties.
Summary: Persimmons contain tannins, a type of compound that may promote constipation by slowing digestion. This may be particularly true for astringent varieties of the fruit.
The Bottom Line
Constipation is an unpleasant condition that’s relatively common.
Luckily, if you have constipation, you can achieve smoother digestion by making some simple changes to your diet.
Start by avoiding or reducing your intake of constipating foods, including the ones listed above.
If you’re still experiencing difficulties after reducing your intake of constipating foods, ask your healthcare provider to recommend additional lifestyle and dietary strategies.