When scientists screw with Fats, they tend to cause serious problems. But, so far [other than the laxative effect...which is the case with anything that is partially absrobed] screwing with Carbs has not caused the same problems. The reason I'm thinking is that Carbs, unlike Fat, serve only to provide calories. They either pass through you unused or are broken down into Glucose to provide energy. Fat [and Protein] OTOH plays many vital roles in our body far beyond simply providing energy. This is likely why screwing with Fats in the lab wreaks such Havoc, while screwing with carbs, doesn't. L-Drugs likely cause problems for the same reasons that Fat does.

My one question is if the body would mistake L-Glucose [as a Simple L-Sugar] for D-Glucose and try to transport it to the cells to provide energy...This wouldn't seem to be a problem with any other L-Sugar or L-Starch as the body only uses Glucose for energy. If it can't break a carb down [as would be the case with other L-Sugars and L-Starches] the carbs would likely simply pass through and out of the body like Fiber.