Question

What is the reason why an itchy feeling is observed when eating not thoroughly cooked taro/gabi leaves?

Answer 1

because they contain a substance (probably a mild poison) which irritates the inside of the mouth.

Answer 2

so maybe you shouldn't eat them :)

Answer 3

Raw Taro leaves contain Calcium Oxalate, this is a toxic substance since it is highly insoluble, forms sharp crystals that irritate mucosa and induces kidney stone formation by clustering there. At low doses, it can already can cause unpleasant sensations in the mouth and swelling of the throat for days.
So for the love of your own health cook those leaves, baking soda seems to accelerate the decay of Calcium Oxalate.

Answer 4

http://everythingisscience.blogspot.com/2007/01/why-does-taro-make-your-throat-itch.html

try taking a look at this site:)