Problem Is the problem a priority?
Judgment	Research evidence	Additional considerations
Probably yes	The glycemic index ranks a carbohydrate containing food according to the amount by which it raises blood glucose levels after it is consumed in comparison with reference food (pure glucose or white bread)6. Dietary approaches that target postprandial glycemic excursions through changes to carbohydrate quality and quantity of the diet might have particular advantages6, 7
Desirable Effects How substantial are the desirable anticipated effects?
Judgment	Research evidence	Additional considerations
Small	Data derived from a meta-analysis recently published8 HbA1c − 0.32 [− 0.45; − 0.19]% in favor of low-glycemic-index nutrients BMI − 0.38 [− 0.64; − 0.16] kg/m2 in favor of low-glycemic-index nutrients
Undesirable Effects How substantial are the undesirable anticipated effects?
Judgment	Research evidence	Additional considerations
Trivial	None8
Certainty of evidence What is the overall certainty of the evidence of effects?
Judgment	Research evidence	Additional considerations
Low	Low for HbA1c; moderate for BMI
Values Is there important uncertainty about or variability in how much people value the main outcomes?
Judgment	Research evidence	Additional considerations
No important uncertainty or variability	No evidence of variability or uncertainty HbA1c and BMI are already considered among critical outcomes of the treatment of type 2 diabetes by scientific societies4−6
Balance of effects Does the balance between desirable and undesirable effects favor the intervention or the comparison?
Judgment	Research evidence	Additional considerations
Probably favors the intervention	Small, but significant reduction of HbA1c and BMI in favor of diet using low-glycemic-index nutrients
Resources required How large are the resource requirements (costs)?
Judgment	Research evidence	Additional considerations
Trivial	No additional costs
Certainty of evidence of required resources What is the certainty of the evidence of resource requirements (costs)?
Judgment	Research evidence	Additional considerations
No included studies	No studies explored this issue
Cost-effectiveness Does the cost-effectiveness of the intervention favor the intervention or the comparison?
Judgment	Research evidence	Additional considerations
No included studies	No studies explored this issue
Equity What would be the impact on health equity?
Judgment	Research evidence	Additional considerations
Probably no impact	No relevant differences in costs and accessibility
Acceptability Is the intervention acceptable to key stakeholders?
Judgment	Research evidence	Additional considerations
Varies	The mean consumption of high glycemic index in Italy is higher than that recommended in diets using low-glycemic-index nutrients14	The acceptability of a low-glycemic-index diet could be problematic for patients with type 2 diabetes living in Italy due to the modifications imposed by this nutritional approach
Feasibility Is the intervention feasible to implement?
Judgment	Research evidence	Additional considerations
Probably yes	No additional resources are required