Priority 16 from the Liver Glycogen Storage Disease (International) PSP

UNCERTAINTY: What is the needed restriction of lactose, fructose or saccharose in different types of liver Glycogen Storage Disease? (JLA PSP Priority 16)
Overall ranking 16
JLA question ID 0090/16
Explanatory note

Guidelines emphasize that lactose, fructose and saccharose are carbohydrates that are have to be strictly avoided in GSD Type I.  
Evidence

For details of the evidence checked, please see the spreadsheet held on the JLA website.
Health Research Classification System category Metabolic and endocrine 
Extra information provided by this PSP
Original uncertainty examples I would like to know retriction of fructose and galactose restriction. What is the best way to go? ~ Can my son have limited amounts of lactose and fructose? I get different answers depending who I speak to. He is type 1A. ~ Can we clear the diet from adolescence concerning lactose and fructose without risk. 
Submitted by  Patient, carer and healthcare professionals
PSP information
PSP unique ID 0090
PSP name International Glycogen Storage Disease PSP
Total number of uncertainties identified by this PSP 72  (To see a full list of all uncertainties identified, please see the detailed spreadsheet held on the JLA website)
Date of priority setting workshop 24 May 2019