potatoes contain some toxic alkaloids, mainly solanine and mucormycone, but the toxic substances will decompose after cooking at a high temperature of 17℃. Solanine poisoning can cause headache and diarrhea.

That is to say, if potatoes are not cooked enough or eaten too much, they will cause diarrhea.

Litchi is warm, and it is easy to get angry when eaten more, which has nothing to do with diarrhea.