Does oatmeal cause constipation?

Are you wondering, ‘Does oatmeal cause constipation?’ The answer is no, the opposite – it helps to relieve constipation due to high fiber content. 

In this article, we will unravel the connection between oatmeal and constipation.

We will also explain the relationship between oatmeal and bloating and suggest how to avoid it.

For all who get bored by eating the same meal all over repeatedly, you can also find our suggestion for oatmeal toppings.

Does oatmeal cause constipation?

No, oatmeal is a beneficial food for promoting regular bowel movements and maintaining digestive health. 

Its high fiber content helps prevent constipation by adding bulk to the stool and supporting healthy digestion. 

Fiber absorbs water and creates a gel-like substance that softens the stool, making it easier to pass through the intestines. 

Therefore, incorporating oatmeal into your diet is unlikely to cause constipation and can help alleviate the condition.

However, constipation can occur if you do not drink enough liquid. Fiber absorbs water; without proper hydration, stools can become dry and hard to pass.

Is instant oatmeal good for constipation?

Yes, instant oatmeal is also good for constipation due to its high fiber content.

Instant oatmeal contains thinner and finely chopped oat grains, whereas regular oatmeal contains only flattened grains (1).

In instant oatmeal, the grains are smaller, which shortens preparation time. 

Even though instant oatmeal is more processed, it is as nourishing as regular oatmeal, so choose the one you prefer.

Does oatmeal cause bloating?

Oatmeal can cause bloating in some individuals due to several reasons. 

Firstly, oatmeal is high in fiber, so if you do not eat it regularly, we suggest you incorporate smaller portions into your diet and gradually increase it over time.

Sudden and significant increases in fiber intake may cause temporary digestive discomfort.

Another reason for bloating is the FODMAP content. Monash University tested various oats and their FODMAP content, yet it differs from product to product. 

A regular 60g portion of uncooked oats is considered a low FODMAP portion with larger amounts  being higher FODMAP (2).

FODMAPs are fermentable carbohydrates. In people with IBS, they can cause bloating and other symptoms, including:

• Abdominal pain
• Flatulence
• Excess gas
• Loose stools

To read more about IBS symptoms, check this article: “What are the symptoms and causes of IBS?”

To avoid those symptoms, try a smaller portion and then increase it. That way, you will identify your tolerance. 
To learn more about oats and IBS, read our in-depth article: “Do oats cause irritable bowel syndrome symptoms?”

How to make oatmeal to treat constipation?

You can prepare oatmeal in many ways, depending on which oats you choose. 

For example, old-fashioned oats need 5-10 min of cooking. On the other hand, rolled oats are ready in the microwave in less than a minute.

To make oatmeal, mix oats with water or use milk or plant-based alternatives, such as almond and rice milk.

When the oatmeal is ready comes the best part – toppings. Toppings not only improve flavor but also increase fiber content and boost the diversity in your diet.

A recent study showed that people who consume at least 30 different plant-based foods have a more diverse microbiome than those who eat ten different plant-based foods or less (3).

A more diverse microbiome is essential for gut health and: 

• Immune system (4)
• Skin health (5)
• Mental health (6)

Here are some ideas for oatmeal toppings to relieve constipation and diversify the diet:

• Fruits, such as blueberries and kiwi fruit
• Vegetables, such as carrots and zucchini
• Nuts, such as walnuts and cashews
• Seeds, such as flaxseeds and chia seeds
• Spices, such as cinnamon and cardamom
• Dark chocolate or cacao nibs

However, this meal may upset your stomach if you have IBS. If this is the case, read our article: “Is porridge good for IBS?”

What foods lead to constipation?

Constipation is not associated with certain foods but with a low-fiber diet. Research shows we should consume 30g of fiber daily (7).

Here you can learn: “How to get 30g of fibre a day”.

To avoid constipation, have regular, high-fiber meals and drink plenty of liquid throughout the day.

That said, constipation can be a side effect of certain food supplements, such as iron (8).

Summary

Oatmeal is a high-fiber meal which can help you relieve constipation. 

When implementing high-fiber meals into your diet, start with smaller portions to allow your digestion to adjust. 

With increasing fiber content, you should also increase fluid intake as fiber soaks up water, and without proper hydration, constipation can occur.

As you make oatmeal, improvise with different toppings which can help you increase fiber content, boost the flavor, and diversify your diet.

Written by Barbara Lešnik, Student Dietitian, reviewed by Kirsten Jackson, Consultant Dietitian BSc Hons, RD, PG Cert