Andrew Huberman· PhD
If you also ingest something that's sour like lemon juice or lime juice, it adjusts the output of those neural circuits in your brain. So again, where you have a situation where you have two parallel pathways, one that's post-ingestive coming from phenomenon within our gut neurons, but also things like gastric emptying time, the clearance and transfer of food, and the conversion of food into particular nutrients and the circulation of glucose in your bloodstream and how it gets into the brain. But also simply by ingesting something sour, you are changing the way that sweet things impact your brain.