I have severe sugar intolerance, if i eat anything from table sugar to fruit it gives me diarrhea. Carb tolerance is a bit better but still really small amounts. What could cause this issues? Sibo, candida or something else?
I'd go with "something else" -- "gut dysbiosis". Have you seen a GI doctor? I doubt they could do much for you, but most other suggestions people will give should be taken with extreme skepticism.