The whole point of Atkins is, it's a ketogenic diet. That is, the object is to eat a low enough carb count to put your body into ketosis or fat burning mode. Normally with carbs we burn glycogen and what we can't burn we store as fat.

So when I eat sugar alcohols, I get tipped out of ketosis and it takes me a few days to get back. This doesn't happen to everyone. Some eat them happily with no effects. Others get insulin spikes from them even though it's claimed they should have no effect on insulin levels.

All in all, I choose to avoid them for my own sake.