I say I have a history of IBS, BUT that needs to be taken with some leeway.
I was having problems with stool being more like constipation or painful in how it came out almost like diarrhea.
I tried several things, and this issue emerged in the last couple of years, not life-long.
This year (beginning) I tried a "colon cleanse" with products from Dr. Natura (http://www.drnatura.com/) chiefly because my research indicated their products were the best rated.
I did a 3-month cleanse, but considering it wasn't the first time I tried cleaning myself out, I probably would have been fine just doing it for one month.
Their Colonix colon cleansing package works great. If you don't use anything else but that, also pick up some of the Flora Protect Probiotics.
Basically, you take herbs, special whole grain fiber, and drink herbal tea every other night to promote regularity. You drink at least 2 liters of water a day for proper hydration. You may or may not flush some gross stuff out (I didn't), but you'll notice in a week or so that your bowel movements are easy, solid, productive and predictable. I think the probiotics are an important part.
After the colon cleanse, I made it a point to make sure I drink enough water every day, and I watch what I eat. If I eat some foods I normally avoid, I wind up with bowel movements that are harder to pass. When I eat the right foods, even without their fiber (I use OTC fiber from the store off the program) I have much easier bowel movements.
So, my "IBS" really was a matter of my body being out of whack. Once it started working right again, the IBS seems to have gone away.