Did you already do his plan? I have read in many places that it is best to start out with very small amounts (some people only eat the juice of the fermented veggies for a while) and then build up. If you dont tolerate I have read that it is better to start wtih probiotic supplementation and then graduate to fermented foods later. If you have not done his plan I suspect your gut flora is severly altered and not quite ready for large amounts of fermented foods. The Selective Carbohydrate Lifestyle (SCD Lifestyle) Guys talk about this too on their website.