Do Pinto Beans or Black Beans Make You Gassier?

November 28, 2025 •

4 min read

According to a 2011 study published in Nutrition Journal, less than half of participants reported increased flatulence after eating pinto beans during the initial weeks of a trial, suggesting that concerns about excessive gas from beans may be exaggerated. This article explores the scientific reasons behind why beans cause gas and tackles the question: do pinto beans or black beans make you gassier?.

Quick Summary

The gassiness from beans is caused by indigestible sugars and fiber, with individual tolerance varying widely. Research shows no definitive answer on which bean is worse, but soaking, rinsing, and gradual intake can significantly help manage discomfort.

Key Points

Individual Variation: The amount of gas produced from eating beans varies significantly from person to person, regardless of bean type.
Oligosaccharides are the Main Cause: Indigestible sugars like raffinose and stachyose are fermented by gut bacteria, causing gas.
Fiber Contributes to Gas: Both pinto and black beans have similar, high fiber content, which can also contribute to flatulence, especially when intake is suddenly increased.
Initial Perception Differs: Early in a 2011 study, a higher percentage of people perceived increased gas from pinto beans compared to black-eyed peas, but this perception decreased quickly with consistent intake.
Preparation is Key: Soaking dried beans, rinsing canned beans, and cooking them thoroughly are the most effective ways to reduce gassiness.
Adaptation is Possible: The more regularly you consume beans, the more your digestive system acclimates, and the less likely you are to experience gas.

The Science Behind Bean-Related Gas

Beans are a powerhouse of nutrition, packed with protein, vitamins, minerals, and dietary fiber. Unfortunately, they are also infamous for causing intestinal gas. The primary culprits are complex carbohydrates known as oligosaccharides, specifically raffinose and stachyose, and a high fiber content.

The Role of Oligosaccharides

Unlike most other carbohydrates, oligosaccharides are not broken down by enzymes in the human small intestine. This is because humans lack the enzyme alpha-galactosidase, which is necessary to properly digest these sugars. Instead, they travel undigested to the large intestine. Here, gut bacteria ferment the oligosaccharides, producing gases such as hydrogen and carbon dioxide. The result is flatulence, bloating, and sometimes, discomfort. The severity of the reaction depends heavily on an individual's unique gut microbiome.

The Impact of Fiber

Both black beans and pinto beans are excellent sources of dietary fiber. While fiber is crucial for digestive health, blood sugar regulation, and cholesterol management, a rapid increase in intake can overwhelm the system, especially for those with low-fiber diets. The fermentation of this fiber by gut bacteria also contributes to gas production. A person's digestive system can adapt over time to a higher fiber intake, leading to a reduction in gas symptoms.

Pinto Beans vs. Black Beans: The Gassiness Comparison

For many, the debate comes down to which type of bean is the greater offender. The short answer is that the difference is likely negligible and highly dependent on the individual.

Nutritional Similarities and Differences

Nutritionally, pinto beans and black beans are quite similar. A one-cup serving of cooked black beans contains around 15 grams of fiber, while a cup of pinto beans has approximately 15.4 grams. The difference in fiber and complex sugar content is so minimal that it is unlikely to cause a noticeable difference in gas production for most people. Any perceived variation is more likely due to individual gut biology than to the bean itself. Both are considered among the more gassy types of beans, along with navy and kidney beans.

Research on Perception of Flatulence

Scientific research supports the idea that perceptions of gas from beans can vary greatly. In the 2011 Nutrition Journal study, only about 50% of participants eating pinto beans reported increased flatulence in the first week, and this perception significantly dropped to just 6% by the second week. This suggests that the body adapts. Notably, a much lower percentage of people experienced initial gas with black-eyed peas, highlighting individual variations in how the body reacts to different legumes. The most authoritative conclusion is that there is individual variation in response to different bean types.

Practical Strategies to Reduce Bean Gas

Instead of eliminating beans from your diet, several simple preparation techniques can significantly reduce their gas-producing potential:

The Power of Soaking: Soaking dried beans overnight helps to dissolve many of the oligosaccharides into the water. Discarding this water and cooking the beans in fresh water is a highly effective step.
Rinse Canned Beans: For canned varieties, rinsing them thoroughly in a colander before cooking flushes away some of the dissolved oligosaccharides and reduces sodium.
Cook Thoroughly: Ensure beans are cooked until they are very soft. Raw or undercooked beans are harder to digest and can contain higher levels of gas-causing compounds.
Increase Intake Gradually: The body adapts over time. Start with small portions of beans and slowly increase your intake over a few weeks to allow your digestive system to adjust.
Use Digestive Enzymes: Over-the-counter supplements containing the enzyme alpha-galactosidase (e.g., Beano) can help your body break down oligosaccharides and prevent gas before it starts.
Add Digestive Herbs and Spices: Adding certain spices like cumin, fennel seeds, or asafoetida (hing) during cooking can aid digestion.

Comparison Table: Pinto Beans vs. Black Beans


Feature	Pinto Beans	Black Beans
Appearance	Mottled brown/pink, turn pinkish when cooked.	Small, oval-shaped with black skin, retain color when cooked.
Flavor	Mild, nutty flavor; absorbs flavors of other ingredients.	Earthy, sweet flavor, can have a slightly meaty texture.
Texture	Creamier when cooked, can easily mush.	Firmer texture, holds its shape well after cooking.
Fiber Content (per cup)	~15.4 grams.	~15 grams.
Digestibility	Similar to black beans; potential for high initial gas perception that decreases with regular intake.	Similar to pinto beans; perceived gassiness is highly individual.

Conclusion: The True Culprit for Gassiness

When comparing do pinto beans or black beans make you gassier, the science reveals they are virtually tied due to their nearly identical nutritional makeup, particularly the presence of oligosaccharides and high fiber content. The perception of gassiness is more of an individual response, heavily influenced by your personal gut microbiome and dietary habits, particularly how frequently you consume beans. Regular consumption can lead to adaptation and reduced symptoms over time. Rather than demonizing one bean over the other, the focus should be on proper preparation techniques, such as soaking and rinsing, and gradually increasing your bean intake. By doing so, you can enjoy the many health benefits of these versatile legumes without the uncomfortable side effects.

For more detailed information on bean health, visit The Bean Institute website to learn about their initiatives and research..

Frequently Asked Questions

Beans contain complex carbohydrates called oligosaccharides that the human body cannot fully digest. These sugars are then fermented by bacteria in the large intestine, a process that produces gas.

Yes, soaking dried beans is a very effective way to reduce gas. The oligosaccharides that cause gas are water-soluble, so they leach into the soaking water. Discarding this water and using fresh water for cooking helps remove some of these compounds.

Yes, studies show that with regular, consistent consumption, your body and gut bacteria can adapt to beans, leading to a decrease in reported gas and discomfort over several weeks.

Rinsing canned beans removes some of the starches and sugars that leach into the canning liquid, which can help reduce the gas-causing effects.

While all beans can cause gas, smaller legumes like lentils and black-eyed peas are sometimes cited as being less gassy. A 2011 study found black-eyed peas caused significantly less perceived flatulence than pinto beans initially.

Yes, digestive enzyme supplements containing alpha-galactosidase, such as Beano, are designed to help break down the complex sugars in beans and other vegetables before they reach the large intestine.

Black beans and pinto beans are both incredibly healthy, with very similar nutritional profiles regarding fiber and protein content. The slight differences in other vitamins and minerals are largely negligible.

Cooking beans until they are very soft and thoroughly cooked is important for digestibility. Using fresh water after soaking and cooking well helps break down the indigestible carbohydrates.