IBS and vegetarian diet?

Yes, I soak dried beans and then pressure cook them. Pressure cooking breaks down sugars in beans, I forgot to include that in my explanation. I have read that canned beans are easier to digest also and assume the cooking process is similar to that of a pressure cooker. Avoid black beans for awhile, I find they are harder to digest which makes sense as they taste sweeter to me.
When using canned beans you might want to rinse them in water to remove the sugars that leached out of the beans during processing.
I have not tried canned lentils but should give them a try.

.... I sometimes wonder about diagnosis of ibs and ibs-d ; never had one issue with bowels until radition to pelvis for cancer cervix stage 2; same with my spouse after anal cancer.... then c.diff 2018 and since then been worse... i reallythought ibs was more like , caused by stress or such if had to give a speach, or nervees. I can eat same thing one week and not be too bad, although still take half an Imodium a day, then eat same thing and it's many b.m.s every one getting more painful til its runny,.... but now am a Senior it's too much to start all over again trying to figure it all out to be honest... thing is for many many years it is not a formed b.m. but very very soft and unformed and its messy and hard to clean up, and its multiple changes of clothing some days and also when have taken Imodium IF it works, then the reverse, like little rabbit poops and they come out on their own! NOthing to wake up through night and it's just come out on its own! sorry to be so descriptive and i try and make jokes about it but its horrible... along with other illnesses to be quite honest its a lot to put up with so my sympathies go to everyone with bowel issues... maybe I could have had a colostomy bag years ago but I have heard they can have their own set of problems and cant eat what you want... best wishes to you all that you find a way to cope for now and future.. J.

There are also pea protein powders that can be added to baked goods to make them high-protein without the whole beans. That may or may not help, depending on what you are reacting to specifically.

This is a recipe that uses flour (though not the protein-only powder I mentioned) in a recipe similar to the dhoklas I mentioned before. It takes out the soaking and grinding steps because you start with the flour. I've never tried it this way, so I can't speak from experience.
https://www.fermentingforfoodies.com/fermented-khaman-dhokla/

Another thought I'll throw out there is that dairy is irritating to my own digestion. That took me a long time to figure out, since I was always eating it and assumed it was part of a healthy diet. My point is that I understand that it's sometimes hard to pin down what is causing what.

Well, beans are a nightmare for my IBS, so I can't give you advice on how to eat them. As far as a quick, alternative vegetarian source of protein for you to subsitute that quickly comes together, you can make a delicious protein patty by mixing pea protein powder isolate (mine is yellow pea protein powder isolate from Azure Market) with a flour of your choice (mine is green plantain flour from LiveKuna) and then adding an egg(s)/egg white(s), liquid, and spices/chopped green onions, etc. You need the egg white to "complete" the pea protein powder, as it is low in one amino acid. It can be cooked in a microwave on a greased plate or in an oiled skillet. Eat the other things your vegetarian family prepares, and if you are like me, after a while, smelling something good is almost as good as eating it (50% of "taste" is in our nose).

I believe I read somewhere or other that oatmeal can be soothing for ibs. I love to play with food and nutrition, so I went on a site called myfooddata.com and made up a recipe for a breakfast porridge that is vegetarian, dairy-free (because of me only, since dairy doesn't agree with me), reasonably high in protein with a decent amount of the essential amino acids, and uses very little legumes. Some of the ingredients I logged in are not very common, but you may be able to find them at health food stores or specialty or ethnic markets if you live in a cosmopolitan area.

1/4 C dry teff grain
1 tsp pea protein powder
1 tsp fenugreek seeds, split(best) or whole or powdered
1 TBSP quinoa grain
4 C water
2 C dry rolled oats
1 medium carrot, grated
1 medium apple, chopped
2 TBSP tahini (sesame butter, like peanut butter but very runny and light in color)
1/2 tsp salt

1 tsp chia seeds

Mix the first four ingredients in the bottom of a large saucepan, one that holds at least 8 C, to give plenty of room since this boils over easily. Stir in a little bit of the water, then the rest of it. Turn heat to low or medium depending on how much time you have and how well you can watch it. Bring to a simmer. I find that on the stove I use, once it is simmering I can keep the heat on the lowest setting. Cook about 10 minutes before adding the carrot. Add the apple and oatmeal 5 minutes later, then cook another 5 minutes--or three if you prefer the oatmeal less cooked.
Stir in the tahini, chia seeds, and salt.

This is a very gooey porridge. I know a lot of people who prefer their oatmeal almost 'al dente'-- this is not one of those recipes! I have no problem enjoying a porridge like this, but it's not to everyone's taste, as it will become almost gelatinous as it cools.

You can actually find a low FODMAP diet for vegetarians/vegans online. It lists foods that are supposed to be "safe" for people with IBS. It is quite restrictive at first, but then you gradually add back foods to see if you react to them in a negative way. You even have to eliminate onions and garlic as well as onion powder and garlic powder. Some people are very sensitive to these ingredients. A work around is to use oil infused with either onion or garlic. You can also eat canned lentils during the elimination part of the diet. It's interesting to find out what foods you react to. It's so sad that many gastroenterologists don't address treatment for IBS. I had one doctor tell me to "go to the bathroom before you go out for a run". Really? 12 years of medical school and that's your advice??? Wow... but seriously, try the low FODMAP approach. It seems to be working for me right now.. Good luck everyone! 🙂

I have tried the low FODMAP protocol a number of times during flare ups and am two weeks into it now but still having some bad days. Since there are periods during which I am able to eat almost everything I’m thinking my issues are more threshold relevant - so if I over load I have trouble rather than if I eat just a small portion of a high FODMAP food. I have the lists of “do and do not eat”foods and the app from Monash university. My PCP attended Monash so he’s familiar with it. I’m seeing a new GI today - because I’m new to the area - so will see what he says. I am just trying to figure out what my possible “permanent” eliminations will have to be within the context of a vegetarian household. I think I will be stuck cooking low FODMAP versions for me since I don’t feel it’s right to impose it on my family - we are of Italian heritage so subbing garlic oil for garlic is tough and my daughter-in-law is a pretty health conscious person so subbing canned lentils for dry in her recipes is probably not something she’d be too thrilled about. I guess I have to understand that if I was living alone I’d be cooking for myself anyway!

For a variation on the recipe I outlined above, you could skip the teff and the protein powder, and increase the quinoa to 1/4 C and the fenugreek and chia to 1 Tablespoon each. The fenugreek seeds give a subtle maple flavor-- in fact an extract from them is sometimes used to create the fake maple syrups. I buy fenugreek seed at two places near me, at a small middle-eastern/east Indian market and also in the medicinal herb/spice ilse of a local healthfood store. Botanically, it's actually classified as a legume!
You could add in another nut or seed such as walnut or sunflower seeds. And you could reduce or eliminate the apple, if it is too much sugar for the low-fodmap approach.
For either version, the total calories for the entire recipe (not per serving) come in about 1500 or less and about 85% or more of your RDI for protein.

I think you are right about the 'threshold' idea and amounts of certain foods. I know a lady who loves avocados, and she used to eat up to 3 at a time! Now she knows to keep it to one at a time, or even half of a large one. That way she can still enjoy one of her favorite foods, just not the same way she used to.