Key takeaways:
Oatmeal can help relieve and prevent constipation because it’s high in fiber.
All types of oatmeal contain fiber, but less-processed types of oats provide more health benefits.
You can add even more fiber to your oatmeal by topping it with fiber-rich foods like nuts, chia seeds, or fruit.
Constipation may be a common condition, but it’s no fun. And maybe you’ve heard that eating certain foods can help you find relief. Some foods are pretty well known for being constipation remedies (prunes, anyone?). But what about the beloved breakfast food oatmeal? Is oatmeal good for constipation?
Read on to learn how oatmeal can help relieve constipation — and help prevent it from happening in the first place.
How does oatmeal help constipation?
There are a few different ways oatmeal can help with constipation.
Good source of soluble fiber
Oatmeal provides 4 g of fiber per ½ cup of uncooked rolled oats (which cooks to roughly 1 cup of oatmeal). Some of this fiber is soluble fiber, which absorbs water in the digestive tract and softens stool. This makes bowel movements easier. Soluble fiber also supports management of blood sugar, cholesterol, and weight.
Provides prebiotic fiber
Some of the soluble fiber in oatmeal is prebiotic fiber. Prebiotics are indigestible carbohydrates that serve as fuel for the healthy bacteria in your gut. By keeping your gut healthy, prebiotics support digestion and normal bowel movements. Getting a combination of prebiotics and probiotics in your diet can be effective for managing constipation.
Contains insoluble fiber
Unlike soluble fiber, insoluble fiber doesn’t absorb water. But it can help constipation by bulking up your stool. This allows food and waste to pass more efficiently through your gut.
And, like soluble fiber, insoluble fiber supports a healthy and balanced weight. That’s because insoluble fiber increases the amount of time food stays in your stomach, which increases the feeling of fullness. Insoluble fiber has also been linked to a lower risk of Type 2 diabetes.
Easy to digest
Some high-fiber foods can cause digestive discomfort, especially if your body isn’t used to them, or if you eat them in large amounts. That’s because certain fibers are fermented by gut bacteria, which in turn can produce gas. Common culprits are beans, lentils, cruciferous vegetables, and some whole grains. But compared to these and some other high-fiber foods, cooked oatmeal is gentle on your gut and easy to digest.
Which is the top high-fiber oatmeal?
All types of oatmeal contain a good amount of fiber, whether they’re made from:
Steel-cut oats (also called Irish oats): These are the least processed type of oats since they’re mostly unchanged from their original form. Steel-cut oats are made by cutting the oat kernel into pieces using a sharp steel blade. That’s where it gets its name. Steel-cut oats have a chewy, dense texture.
Rolled oats (sometimes called old-fashioned oats): Rolled oats are in the “slightly processed” category because they’re steamed and flattened. This gives them a soft and creamy texture and flavor compared to steel-cut oats, and a quicker cooking time.
Quick oats: These oats are similar to rolled oats, but flattened even thinner so they can cook in under 5 minutes.
Instant oats: These oats are the most processed. They’re steamed, flattened, and partially precooked, so they cook in as little as a minute in the microwave.
All oats contain nearly the same amount of fiber per serving. But they affect your body in different ways.
Steel-cut oats have the lowest glycemic index (GI). The glycemic index is a measure of how a food affects your blood sugar. Instant oatmeal has the highest GI, meaning it will raise your blood sugar the most drastically. These differences in GI are caused by the different shapes and levels of processing of the oats. Whether you have diabetes, emphasizing lower GI foods in your diet will help maintain normal blood sugar levels.
And note that while instant oats (the kind that comes in packets) are convenient, they often contain food additives. Check the nutrition label for added sugars, and try to choose those with low or no sugar. Also check for artificial sweeteners — such as sucralose — or artificial colors and preservatives. These are all things that suggest the oatmeal is more highly processed and less nutritious for your body.
How to eat oatmeal for constipation
A typical serving size of oatmeal is ½ cup of dry oats. This will cook to about 1 cup of oatmeal.
If you’re eating oatmeal for constipation, you can boost the fiber in your meal by adding high-fiber toppings and mix-ins, such as:
Nuts (like almonds, pecans, and walnuts)
Seeds (like pumpkin, chia, and flaxseed)
Frozen fruit or fresh fruit
And, since oatmeal on its own isn’t a high-protein food, you can make a complete meal by adding protein foods like:
Milk
Nuts and/or seeds
If you want to sweeten your oatmeal, try using ripe fruits or a small amount of natural sweetener like honey or maple syrup.
One note of caution: If you increase fiber intake too quickly, it can lead to digestive discomfort, like bloating or gas. It can even lead to constipation. Your digestive tract needs time to adapt to a higher-fiber diet. So if your body isn’t used to consuming high amounts of fiber, start slowly, and increase your fiber intake gradually. And be sure to drink enough water. Water is necessary for fiber to do its job.
What is the best breakfast for constipation?
Oatmeal isn’t the only breakfast food that can help with constipation. To relieve or prevent constipation, try to get in the habit of choosing breakfast foods that contain some combination of:
Fiber (from whole grains, fruits, or veggies)
Water (from hydrating fruits and vegetables)
Probiotics,live yeasts and bacteria that support the natural flora in your intestine (found in some yogurts, sourdough bread, and other fermented foods and drinks)
Examples of breakfasts that check one or more of these boxes are:
Whole-grain or sourdough toast topped with avocado or peanut butter and banana
Yogurt that contains live and active cultures
Smoothies containing kefir or Greek yogurt
Chia seed pudding
High-fiber cereal or granola made with whole grains and seeds
Cottage cheese with fruits like berries, oranges, and pears
Omelets or egg scrambles with veggies
Whole-grain pancakes or waffles topped with fruit
Frequently asked questions
Oatmeal doesn’t usually cause constipation. It often helps prevent it. But if you increase your intake of oatmeal (or other high-fiber foods) without drinking enough water, it can slow down digestion and lead to constipation. Fiber requires water in order to do its job. So if you’re boosting fiber intake, be sure to drink plenty of water. And try to increase fiber gradually, not suddenly.
If you’re constipated, it’s best to avoid highly processed, no-fiber, or low-fiber foods. Examples include fast food, anything made with white flour (bread, pretzels, white pasta), and sugary snacks. Instead, emphasize high-fiber foods like fruits, vegetables, whole grains, and legumes. A good rule of thumb is to include fiber in every meal and snack. This will help you meet the daily recommendation of around 25 g for women and 38 g for men.
Oatmeal doesn’t usually cause constipation. It often helps prevent it. But if you increase your intake of oatmeal (or other high-fiber foods) without drinking enough water, it can slow down digestion and lead to constipation. Fiber requires water in order to do its job. So if you’re boosting fiber intake, be sure to drink plenty of water. And try to increase fiber gradually, not suddenly.
If you’re constipated, it’s best to avoid highly processed, no-fiber, or low-fiber foods. Examples include fast food, anything made with white flour (bread, pretzels, white pasta), and sugary snacks. Instead, emphasize high-fiber foods like fruits, vegetables, whole grains, and legumes. A good rule of thumb is to include fiber in every meal and snack. This will help you meet the daily recommendation of around 25 g for women and 38 g for men.
The bottom line
Oatmeal can help with constipation because it contains different kinds of fiber, including prebiotic fiber. Eating oatmeal — and drinking enough water throughout the day — helps to soften your stool and move through your digestive tract. All types of oats contain fiber, but some types of oatmeal are more processed than others. Whatever type of oatmeal you eat, try to avoid added sugar and artificial ingredients. You can add your own natural sweeteners and mix-ins to suit your preferences — and boost the nutrients of your meal.
Why trust our experts?
References
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Farag, M. A., et al. (2020). The many faces of kefir fermented dairy products: Quality characteristics, flavour chemistry, nutritional value, health benefits, and safety. Nutrients.
Hervik, A. K., et al. (2019). The role of fiber in energy balance. Journal of Nutrition and Metabolism.
Larson, H. (2025). Easy ways to boost fiber in your daily diet. Academy of Nutrition and Dietetics.
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National Institute of Diabetes and Digestive and Kidney Diseases. (2018). Eating, diet, & nutrition for constipation. National Institutes of Health.
Surampudi, P., et al. (2016). Lipid lowering with soluble dietary fiber. Current Atherosclerosis Reports.
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