Hi Marri! Great question! Sorbitol is a tricky one to test with as there is lots of conflicting information out there, and most fruits that contain sorbitol are also high in another FODMAP. I don't recommend peaches for testing sorbitol, because they do contain fructose. The choices I usually give my patients are - Blackberries, 6 for the first test, 12 for the second and if they pass with flying colours, I usually get them to also try Lifesavers Sugar Free Mints sweetened with sorbitol (I've found them at Walmart, they're tricky to find) - 2 candies the first test, 4 for the second test - since this is a controlled dose of sorbitol. There is a lack of consensus around how much sorbitol is found in various fruits; I believe this is due to the ripeness (the firmer the fruit the more the sorbitol) - so that's why I usually do a back-up test to confirm - especially if they think they may be sensitive and are surprised by doing so well with blackberries. Usually, I only see sorbitol intolerance in IBS-D - as the sugar alcohol is poorly absorbed and tends to pull water into the bowel - so that's something to keep in mind; the type of IBS you have may be helped or hindered by sorbitol. I hope that helps! - Andrea Hardy, RD