Chewing different materials affects the brain and a new study found that chewing on wood (wooden tongue depressors), compared to chewing gum, led to a significant increase in a natural brain antioxidant called glutathione, and better performance on memory tasks.

[u/mvea]

https://www.psypost.org/chewing-wood-may-boost-memory-and-brain-antioxidants-study-finds/

[u/roamingandy]

Not sure they'd work as you're eating carrots rather than chewing on them for a prolonged time like wood or gum.

[u/eliminating_coasts → u/roamingandy]

I think if chewing is the thing that causes the effect, there's not much harm in eating a vast quantity of uncooked and peeled but unchopped carrots - they're not particularly energy dense, high in fibre and vitamins etc. so you probably could just keep munching carrots like a horse for hours without having a significant negative effect.

[u/masklinn → u/eliminating_coasts]

Carrots are more crunchy than chewy. You go through them fast.

I’d suggest liquorice roots. They are quite woody and chewy, and I prefer the taste of the raw root to that of liquorice sweets.

[u/samsaruhhh → u/masklinn]

It's not difficult to overdose on licorice if I'm remembering correctly, it can raise blood pressure, lower potassium levels, affect heart rhythms among other things..

[u/istara → u/samsaruhhh]

Also to be avoided in pregnancy and breastfeeding.