When we start a new regiment, it is sometimes best to incorporate changes slowly. It sounds like there are some trigger foods in the LEAN program that you may want to consume in small amounts, at least a first. Everyone has different trigger foods so we recommend experimenting.
Here are some common trigger foods for heart burn: http://www.webmd.com/heartburn-gerd/triggers
When you consume too much fiber initially, you can feel bloated. Try consuming 1/2 a serving for the first couple of days and get your body situated. Increase serving sizes to a full tall cup. If you are still feeling bloated, stay with it a couple of days and consume more liquids to get things moving. If you are able and capable, I would recommend adding a little walking to get your bowels moving. As always, check with your doctor if you feel your GI tract is not functioning regularly.