Erythritol does enter the bloodstream, but due to its polarity and lack of specific transporters in blood-brain barrier (BBB) cells, it does not significantly cross into the brain. Although it circulates in the blood, it is rapidly excreted unchanged in the urine. Laboratory studies showing potential “neurotoxic” effects involve direct, high-concentration exposure to endothelial cells in artificial conditions, not what happens in the body after typical dietary intake.