I have found a diet that puts my IBS-D into full remission. It's the SCD diet. It's basically meat, fruit, non-starchy vegetables, homemade yogurt (I use goat milk to make this because I can't tolerate cow dairy), and honey for sweetener. All my intestinal pain and loose stools stop with this diet. I believe I have a lot of healing to do with my gut though. As for POIS it's too early to say but I've had some mild improvement so far. I like the diet because unlike carnivore or keto I don't feel like I'm missing out on important nutrients.