Q: Do Beans Give you Gas?
Saturday, July 24th, 2010 by Health FoodieIf there were a competition for the “unsexiest food”, beans would probably win, closely followed by prunes. The reason for this is beans’ association with gas… lots of gas! Some people claim that eating beans has no effect on them, while others go so far as to avoid eating beans altogether due to their unpleasant side effects. So who is right? Do beans really make you gassy or are they being unjustly accused?
It’s not that simple
As you probably guessed, the answer is: it depends. There are two factors that make beans a potential gas inducer. How much, or if at all, these two factors affect a person depends on how the beans are prepared, unique body chemistry, and general eating habits of that person. I will discuss each factor in turn.
Indigestible sugars
Can’t break that bond
Beans and some other vegetables (e.g. cabbage) contain oligosaccharides such as raffinose and stachyose. Oligosaccharides are just simple sugar molecules connected in a short chain (3-10 simple sugars long). Unfortunately, our bodies lack an enzyme to break these chains up. The chains themselves are too large to be absorbed in the intestine and we therefore do not metabolize them. Therefore, these sugar chains travel unbroken through our intestine until they end up in the large intestine.
Bacteria are hungry too
Once in the large intestine, bacteria, which are able to break the bonds, start feasting on them. A metabolic byproduct of this feast is — you guessed it — gas. This gas then travels further in the intestine until… well I guess we all no where this is going.
What can I do about it?
One solution is to take the enzyme which breaks up the oligosaccharides with your meal. This way the oligosaccharides won’t reach your large intestine where bacteria metabolize them. There are several such commercial products available, e.g. Beano.
Oligosaccharides are water soluble, and leach out into the water when beans are soaked. Soak beans for at least eight hours in cold water in the refrigerator and rinse them well before cooking in order to get rid of some oligosaccharides.
Did you know… ?
Fermented beans generally cause less of a problem. The yeast that is used to ferment the beans is able to break the bonds of oligosaccharides, so they are not available for breakdown by the bacteria in your intestine.
Insoluble fiber
More food for bacteria
Fiber comes in many different forms. Insoluble fiber is not metabolized by our bodies and therefore travels through the large intestine and ends up in our stool. Certain types of insoluble fiber can be broken down by various bacteria, again producing gas.
Switching to a high fiber diet
This is one of the reasons why bloating is a common side effect of switching to a high fiber diet. However, after a while, changes in the body take place and the bloating reduces — this is why many people who already eat a lot of fiber do not experience bloating from eating beans. In general, it is recommended to increase the amount of fiber in a diet gradually. If you do not eat very much fiber, the large amount in beans could cause discomfort.
Differences among people
Everybody has different kinds and amounts of bacteria in their guts. This means that one type of fiber can bother one person, but have no effect on another. For instance, you could be used to a certain type of fiber, while the fiber in beans still bothers you. In this case, you could try to gradually increase the amount of beans you eat. Unfortunately, it is entirely possible that beans simply do not agree with you.
Cooking Tip
There are certain spices which help to ease bloating, by either reducing how much gas is formed in the first place or by making sure the gas gets out (easing discomfort). These spices are called carminatives and include peppermint, cumin, cinnamon, dill, basil, coriander, thyme, rosemary, ginger, fennel and others. Good thing that beans go so well with many of these!
When nothing helps
Seeing the positive
If nothing helps and beans just make you gassy, it may make you feel better to know that it is at least good for your body. The main bacteria that you will feed with oligosaccharides and fiber are healthy ones such as lactobacillus bifidus (also found in yogurt). Maybe knowing that the gas is a sign that you are nourishing these little helpers will help you tolerate the pain and smell… or maybe not.
It’s all about timing
If beans are problematic for you, just make sure you eat don’t them when you are about to be in closed rooms with lots of people. If you eat them before bed, the worst thing that can happen is that you will wake up finding your blanket hovering over you and your partner in the other room. ☺
- Christina




Awesome article Christina! Good see you in the blogosphere again.
We’ve been eating a lot of beans/legumes around our house lately, in hummus, cannellini bean dip, black bean burgers, and lentil soup. I think in people who consume a habitual high fiber diet, beans don’t cause so many unpleasant side effects, but it’s good advice to work up your fiber intake gradually.
And sleep with a window open. :) Georgie http://www.Askgeorgie.com
Thank you Georgie! Mhh I love beans and legumes, making me hungry with your list!
Haha, I always slept with my window open in Switzerland (for other reasons…) and I hate how I can’t open the windows here sometimes because of the AC.
Hehehehehe!! I love the topic of this post :-)
In regard to your comment on my blog – yes the scallops did taste a little bit burnt. They weren’t the best scallops I have ever had.
Haha me too ☺
Thanks for answering my question!
You’re so smart. I never have a problem with beans and now I know why. I already eat a lot of fiber and I soak them before cooking. :-)
Jenn! ☺
Great! Thanks for confirming that there are indeed people who have no problems with beans!
Glad to see you back at posting AMAZING posts!!
Thx for the infos about those sneaky little gas producers! ;)
Thank you Nic! I am glad to be back too! ☺
I am so happy you are back! I had a terrible time with gas until I had my gall bladder removed. There has to have been a connection, & with other health issues. I’ve heard that green peppers, (sweet, capsium (sp?) can be a problem. Bean are generally a plus in our diets, aren’t they? Of course, there must be a significant difference between dried beans and string beans etc. Maybe they really are not related?
Happy to be back too! Sorry to hear that about your gallbladder. Glad you are feeling better.
I have heard that too, that some people don’t do well with peppers. It could be the fiber (people who otherwise get very little fiber), or the fact that bell peppers also contain oligosaccharides. Some people might also be sensitive to bell peppers (you can be sensitive to almost anything) which might lead to bloating, although that would probably be rare.
Yes, beans are definitely great for your health! They contain lots of fiber, valuable minerals and vitamins and lots of antioxidants (the darker the bean the more antioxidants). Green beans are very healthy as well. In nutrition green beans are looked at as a vegetable and beans/legumes are counted as a “meat”. So while they are definitely related (green beans are the unripe fruit of the bean plant, while the “bean” is the large seed of the bean plant.) they are different nutritionally. Green beans who count as a vegetable are lower in calories (lower in protein and carbs) and contain lots of different vitamins and minerals. Both are part of a healthy diet.