I was diagnosed with one of the most extreme IBS cases my GI doc had ever seen. Colonoscopy/upper endoscopy showed I was totally healthy with minor inflammation and a polyp (very unusual for my age - I'm 25, had colonoscopy at 24). I had been having IBS since I was 18, but it was very mild until age 21 when it became mildly annoying and it abruptly became terrible at age 23.
I will spare you the details on how it affected my life - I am sure you can imagine how bad it was. (Nothing like bloating another "I'm cured!" topic with complaints and unnecessary details... we have enough bloating in our lives with IBS!).
Loose stools 2x/day, unable to get clean after pooping (incurable mud butt - it was like wiping a sharpie every time I went), poop sometimes felt like fire when I went to the bathroom; after a few years, I began having gas pains, searing hot farts, and basically always felt bloated.
I have a 32 waist size but had to wear Large and XL boxers because the waste bands felt tight around my intestines and made gas worse.
I also found out I have low B12 and low Folic Acid levels... not quite anemic, but close. Pain was becoming debilitating in the last few months; felt like I was poked with a knife when I simply touched my stomach, and it was reaching a point where I couldn't even work out despite a very high pain tolerance.
I tried supplements, probiotics, elimination diets (BRAT made me feel terrible), blood test, a colonoscopy, and my GI doc was suggesting outlandish things like going to a rectal prolapse surgeon! (WHY?!)
Eliminating grains and starches and dairy from my diet. I also cannot consume peanuts. I add in L-Glutamine, N-Acetyl Glucosamine, and OMEGA-3 with D3 daily to further reduce inflammation in case I consume some. This is not a food allergy - allergy testing showed negative for all of these. I think my condition is akin to a lactose intolerant person not being allergic to dairy, but they simply cannot consume it because they don't produce sufficient lactase to break it down. Consider how ubiquitous grain is in the Western diet - I was eating granola bars at breakfast, rice with chicken at lunch, and a sandwich (ex grilled cheese) for dinner. No wonder I was in such agony...
I found my cure by cycling through completely different style meals for breakfast, lunch, and dinner; when I started realizing that I had reduced bloating after breakfast (oatmeal and bananas) and that I could eat it all day and not have stomach problems, I realized I was onto something! It's worth noting that I had temporary cures with VSL #3 and L-Glutamine - still not sure what to make of that, as both stopped working after a matter of weeks.
I do not have celiac - gluten is agreeable with me, and gluten free doesn't help whatsoever - and I can even eat oatmeal, oddly enough, but all other grains and dairy products make me inflamed and gassy and give me poops where I have to shower to get clean. I'll add that when I am not eating any grains, I go to the bathroom every other day; when I eat grains, I go 2x/day. For some reason, white grains are infinitely more agreeable than whole wheat/brown grains.
As for dairy, it appears that like many young adults, I (coincidentally) developed lactose intolerance around the same time that my wheat allergy appeared.
When I cut out wheat and dairy, it took 48-72 hours before my GI system "reset" and all inflammation was completely reduced and bowel movements returned to normal. I eat a spartan diet of meat and veggies now 5-6 days of the week. I find that if I treat my body very well for several consecutive days, I can eat something with bread or chocolate and I don't die... but if I start eating those foods back-to-back it's bad!
I am back to Medium/Large boxers - still not quite as comfortable as they once were, but I'm getting there! I hope this helps someone. I had seen someone suggest a wheat free diet... I waited way too long to try it... if you are a healthy person with IBS-D and you have not tried a grain free diet, you owe it to yourself to try this for 3-4 days.
If anyone needs recommendations for brands for the supplements, feel free to ask. The OMEGA-3 is great quality and has high levels of D3 built into it. Both OMEGA-3 and D3 are helpful for reducing IBS-D according to peer reviewed studies (which get censored when I try to link to them...seriously?!). The reality is, some brands make better vitamins/supplements than others, but many brands work.
I am meeting with my GI doctor to discuss having some breath testing done. I am guessing that I don't have the enzymes necessary to break down some of these foods. For some reason, I also can't consume peanuts, marinara, and a few other random things - it doesn't make much sense to me (I'm open to theories if you guys have any). I thought I had pernicious anemia, bacterial overgrowth, or something else, but apparently not... if anyone has any questions, ask away. I pray this helps some of you guys. No one should live like this.