Constipation is a common and uncomfortable condition that affects many people around the world. It is defined as having less than three bowel movements per week, or having difficulty passing stools that are hard, dry, or lumpy.
Constipation can have various causes, such as low fluid intake, lack of physical activity, stress, medication use, or underlying medical conditions. However, one of the most important factors that influences bowel function is diet.
Diet can either help prevent or relieve constipation, or make it worse. Some foods can promote regularity by providing fiber, water, and beneficial bacteria to the gut. On the other hand, some foods can cause or worsen constipation by being low in fiber, high in fat, or triggering digestive issues.
This article will examine some of the foods that can cause constipation, based on scientific evidence and expert opinions. It will also provide some dietary tips to help prevent or treat constipation.
Fiber is a type of carbohydrate that is not digested or absorbed by the body. It passes through the digestive tract and adds bulk and softness to the stools, making them easier to pass. Fiber also helps regulate bowel movements by stimulating the muscles of the colon and promoting the growth of beneficial bacteria in the gut.
The recommended daily intake of fiber for adults is 25–38 grams, depending on age and sex. However, most people do not meet this recommendation and consume an average of only 15 grams per day.
Eating a diet that is low in fiber can contribute to constipation. Foods that are low in fiber include:
- Dairy products
- Refined grains (such as white bread, white rice, white pasta)
- Sweets and desserts
- Processed foods
These foods do not provide much bulk or moisture to the stools and may slow down intestinal transit. They may also displace high-fiber foods from the diet, such as fruits, vegetables, whole grains, legumes, nuts, and seeds.
To increase fiber intake and prevent constipation, it is advisable to eat more plant-based foods that are rich in fiber. These include:
- Fruits (such as apples, pears, berries, prunes)
- Vegetables (such as broccoli, carrots, spinach, kale)
- Whole grains (such as oats, barley, quinoa, buckwheat)
- Legumes (such as beans, lentils, chickpeas)
- Nuts and seeds (such as almonds, walnuts, flaxseeds)
However, it is important to increase fiber intake gradually and drink plenty of water along with it. Adding too much fiber too quickly can cause gas, bloating, cramps, or diarrhea. Drinking enough water helps fiber absorb water and form soft stools that are easy to pass.
FODMAPs are short-chain carbohydrates that are poorly absorbed in the small intestine and fermented by bacteria in the large intestine. FODMAPs stand for fermentable oligosaccharides (such as fructans and galacto-oligosaccharides), disaccharides (such as lactose), monosaccharides (such as fructose), and polyols (such as sorbitol and xylitol).
Some people may be sensitive to FODMAPs and experience digestive symptoms such as gas, bloating, constipation, or diarrhea when they eat foods that contain them. This is especially common in people with irritable bowel syndrome (IBS), a functional disorder that affects the gut-brain axis and causes abdominal pain and altered bowel habits.
Some examples of high-FODMAP foods include:
- Brussels sprouts
- Agave nectar
- High-fructose corn syrup
- Ice cream
- Soy products
- Sugar alcohols
These foods can cause constipation by increasing gas production and distension in the colon, which can impair its motility and slow down stool passage. They may also alter the gut microbiota composition and function, which can affect bowel movements.
To reduce the risk of constipation caused by FODMAPs, it may be helpful to follow a low-FODMAP diet under the guidance of a registered dietitian. A low-FODMAP diet involves eliminating high-FODMAP foods for a period of time, then reintroducing them gradually to identify personal triggers and tolerance levels.
Some examples of low-FODMAP foods include:
- Green beans
- Bell pepper
- Maple syrup
- Lactose-free milk and dairy products
- Hard cheeses (such as cheddar, parmesan, swiss)
However, a low-FODMAP diet is not suitable for everyone and should not be followed long-term, as it may reduce the intake of prebiotics and affect the diversity and health of the gut microbiota. Therefore, it is important to consult a healthcare professional before starting this diet and to follow it only as long as necessary.
Other Foods That May Cause Constipation
Besides low-fiber and high-FODMAP foods, there are some other foods that may cause constipation in some people. These include:
Bananas are a popular fruit that can have different effects on bowel function depending on their ripeness. Unripe or green bananas contain a high amount of resistant starch, a type of indigestible carbohydrate that can cause gas and bloating in some people. Ripe or yellow bananas contain more soluble fiber, which can help soften stools and ease constipation. However, some people may find that eating too many ripe bananas can also cause constipation by adding too much bulk to the stools.
The effect of bananas on constipation may vary from person to person and depend on other factors such as fluid intake, overall fiber intake, and gut health. To prevent constipation, it may be advisable to eat bananas in moderation and choose ripe ones over unripe ones.
Chocolate is a delicious treat that many people enjoy, but it may also have a negative impact on bowel function. Chocolate contains caffeine, which can have a dehydrating effect and reduce the moisture content of stools. Chocolate also contains cocoa, which can stimulate the release of serotonin, a neurotransmitter that can relax the muscles of the colon and slow down intestinal transit. Moreover, chocolate is high in fat and sugar, which can also contribute to constipation by displacing high-fiber foods from the diet.
The effect of chocolate on constipation may depend on the amount and type of chocolate consumed, as well as individual sensitivity. Dark chocolate contains more cocoa and caffeine than milk or white chocolate, so it may have a stronger effect. To prevent constipation, it may be wise to limit chocolate intake and choose dark chocolate over milk or white chocolate, as it also contains more antioxidants and less sugar.
Cheese is a dairy product that is high in protein, calcium, and fat, but low in fiber and lactose. Cheese can cause constipation in some people by being low in fiber and high in fat, which can slow down digestion and stool passage. Cheese can also cause constipation in people who are lactose intolerant or allergic to milk proteins, as these can trigger inflammation and impair gut motility.
The effect of cheese on constipation may depend on the type and amount of cheese consumed, as well as individual tolerance. Hard cheeses (such as cheddar, parmesan, swiss) contain less lactose and more fat than soft cheeses (such as brie, camembert, cottage cheese), so they may have a different effect. To prevent constipation, it may be beneficial to limit cheese intake and choose hard cheeses over soft cheeses, or opt for lactose-free or plant-based alternatives.
Dietary Tips to Prevent or Relieve Constipation
Besides avoiding or limiting the foods that can cause constipation, there are some dietary tips that can help prevent or relieve constipation. These include:
Drink plenty of fluids
Fluids help keep the stools moist and soft, making them easier to pass. Dehydration can cause the stools to become hard and dry, leading to constipation. The recommended daily intake of fluids for adults is about 2–3 liters, depending on age, sex, activity level, climate, and health status. Water is the best choice of fluid, as it is calorie-free and hydrating. Other fluids that can help prevent or relieve constipation include:
- Fruit juices (such as prune juice, apple juice, pear juice)
- Vegetable juices (such as carrot juice, beet juice, tomato juice)
- Herbal teas (such as chamomile tea, peppermint tea, ginger tea)
- Coffee (in moderation)
However, some fluids that can worsen constipation include:
- Alcohol (as it can have a dehydrating effect)
- Carbonated drinks (as they can cause gas and bloating)
- Milk (if lactose intolerant or allergic)
Eat probiotic foods
Probiotics are beneficial bacteria that live in the gut and help maintain its health and function. Probiotics can help prevent or relieve constipation by improving stool consistency, increasing stool frequency, and stimulating intestinal motility. Probiotics can also modulate the gut-brain axis and reduce stress, which can affect bowel function.
Probiotic foods are foods that contain live and active cultures of probiotics. Some examples of probiotic foods include:
However, not all probiotic foods are equally effective for constipation, as different strains of probiotics may have different effects. Some of the most studied and beneficial strains for constipation include:
- Bifidobacterium lactis
- Lactobacillus casei
- Lactobacillus rhamnosus
- Lactobacillus plantarum
To prevent or relieve constipation, it may be helpful to eat probiotic foods regularly and choose those that contain these strains or a combination of them. Alternatively, probiotic supplements may also be an option, but they should be taken under the supervision of a healthcare professional.
Eat prebiotic foods
Prebiotics are non-digestible carbohydrates that feed the probiotics in the gut and help them grow and thrive. Prebiotics can help prevent or relieve constipation by increasing stool bulk, softening stool consistency, and enhancing intestinal motility. Prebiotics can also modulate the gut-brain axis and reduce inflammation, which can affect bowel function.
Prebiotic foods are foods that contain prebiotics. Some examples of prebiotic foods include:
- Chicory root
- Jerusalem artichoke
- Dandelion greens
However, some prebiotic foods are also high-FODMAP foods, which may worsen constipation in some people who are sensitive to them. Therefore, it is important to find a balance between prebiotic intake and FODMAP tolerance. To prevent or relieve constipation, it may be beneficial to eat prebiotic foods regularly and choose those that are low-FODMAP or well-tolerated.
Constipation is a common and uncomfortable condition that can have various causes, but diet is one of the most important factors that influences bowel function.
Some foods can cause or worsen constipation by being low in fiber, high in fat, or triggering digestive issues. These include low-fiber foods (such as meat, dairy products, eggs, refined grains, sweets, desserts, processed foods), high-FODMAP foods (such as wheat, rye, barley, onion, garlic, artichoke, asparagus, Brussels sprouts, cabbage, cauliflower, mushrooms, apples, pears, watermelon, mango, honey, agave nectar, high-fructose corn syrup, milk, yogurt, ice cream, cheese, beans, lentils, chickpeas, soy products, sugar alcohols), and other foods (such as unripe bananas, chocolate, and cheese).
To prevent or relieve constipation, it is advisable to avoid or limit these foods and eat more plant-based foods that are rich in fiber (such as fruits, vegetables, whole grains, legumes, nuts, and seeds), drink plenty of fluids (especially water), eat probiotic foods (such as yogurt, kefir, sauerkraut, kimchi, miso, tempeh, kombucha), and eat prebiotic foods (such as chicory root, Jerusalem artichoke, dandelion greens, garlic, onion, leek, asparagus, banana, oats, barley, flaxseeds).
However, the effect of food on constipation may vary from person to person and depend on other factors such as fluid intake, overall fiber intake, and gut health. Therefore, it is important to consult a healthcare professional before making any dietary changes and to follow a balanced and varied diet that meets individual needs and preferences.