Structured population data were available for 3 of 3 supporting studies. 1 study described participants with type 2 diabetes. 3 studies described adult participants.

Healthy Diet with Standard Macronutrient Ratio

Core clinician-reference fields are available or not applicable.

Participants followed a diet where they consumed normal calories for 5 days and restricted to 500-600 kcal for 2 non-consecutive days.

Intermittent Fasting 5:2

Intermittent Fasting 5:2 Diet: In this diet, the participants were required to continue their normal calorie intake for 5 days a week, while for 2 non-consecutive days per week, they consumed only 25% of their daily caloric needs in a typical day (500–600 kcal per day).

A plant-based diet with a macronutrient distribution of 40% carbohydrates, 20% protein, and 40% fat.

Portfolio Moderate-Carbohydrate

Portfolio-moderate-carbohydrate diet: This is a plant-based diet with a macronutrient distribution of 40% carbohydrates, 20% protein, and 40% fat based on each individual's total caloric requirement.

Daily calorie intake restricted to 75% of total calorie intake with anti-inflammatory recommendations.

Anti-Inflammatory

Anti-inflammatory diet: In this diet, daily calorie intake was restricted to 75% of the total calorie intake per day with selecting the nutrients according to the anti-inflammatory recommendations.

Participants followed a healthy diet with a daily calorie restriction of 75% of daily energy requirements.

Control group: Due to ethical considerations, non-intervention in the control group may lead pre-diabetic participants to progress to diabetes. Therefore, a healthy diet with a daily calorie restriction (75% of daily energy requirements) with the standard macronutrient ratio of 50% carbohydrates, 20% protein, and 30% fat was considered as the control group.

Authoritative quality diagnostic: invalid or missing unit.

Authoritative quality diagnostic: invalid or missing value.

Dietary interventions improve glycemic control in pre-diabetic patients

Control Group (CG)

Participants received nutritional education strategies based on a low-carbohydrate dietary approach delivered remotely.

Intervention Group (IG)

In this group, nutritional education strategies were implemented based on a low-carbohydrate dietary approach. The educational sessions were delivered entirely remotely through a smartphone messaging application (WhatsApp).

Participants received conventional management for T2DM.

In contrast, the CG exhibited significant increases in fasting glucose and Body Mass index, with no significant HbA1c change.

Online education improves glycemic control in type 2 diabetes management

Conventional diabetes diet

Participants received a carbohydrate-reduced high-protein diet for 6 weeks.

Carbohydrate-reduced high-protein diet

Participants were randomly assigned to 6 weeks of a carbohydrate-reduced high-protein (CRHP) or a conventional diabetes (CD) diet.

Participants received a conventional diabetes diet for 6 weeks.

Weight loss improves heart rate variability in type 2 diabetes

Structured population data were available for 3 of 3 supporting studies. 2 studies described participants with type 2 diabetes. 3 studies described adult participants.

1 supporting study does not have a displayable topic-matched quantitative effect.

1 study contains conflicting p-value and significance fields; those significance claims are suppressed.

Structured population data were available for 4 of 4 supporting studies. 3 studies described participants with type 2 diabetes. 4 studies described adult participants.

Upstream consistency scoring indicates mixed findings across the evidence.

Evidence uses heterogeneous comparison contexts: active_comparator, usual_care.

Structured population data were available for 8 of 8 supporting studies. 4 studies described participants with type 2 diabetes. 8 studies described adult participants.

1 relevant study has unresolved authoritative design evidence and does not contribute to design-specific or RoB-specific claims.

Evidence uses heterogeneous comparison contexts: baseline_within_group, unknown_unresolved, usual_care.

2 supporting studies have high, serious, critical, unclear, or unavailable risk-of-bias information.

Evidence uses heterogeneous comparison contexts: baseline_within_group, usual_care.

2 supporting studies do not have a displayable topic-matched quantitative effect.

Evidence uses heterogeneous comparison contexts: active_comparator, unknown_unresolved.

3 supporting studies have high, serious, critical, unclear, or unavailable risk-of-bias information.

Structured population data were available for 4 of 4 supporting studies. 4 studies described participants with type 2 diabetes. 4 studies described adult participants.

Structured population data were available for 5 of 5 supporting studies. Diabetes type was heterogeneous: 2 studies with type 1 diabetes, 1 studies with type 2 diabetes. Age groups were heterogeneous: 2 studies with adult participants, 1 studies with youth participants.

2 relevant studies have unresolved authoritative design evidence and do not contribute to design-specific or RoB-specific claims.

Evidence uses heterogeneous comparison contexts: baseline_within_group, other, usual_care.

4 of 5 studies with duration data have follow-up of 12 weeks or less.

Structured population data were available for 10 of 11 supporting studies. Diabetes type was heterogeneous: 5 studies with type 2 diabetes, 2 studies with type 1 diabetes. 8 studies described adult participants.

3 relevant studies have unresolved authoritative design evidence and do not contribute to design-specific or RoB-specific claims.

3 supporting studies do not have a displayable topic-matched quantitative effect.

Evidence uses heterogeneous comparison contexts: active_comparator, baseline_within_group, placebo, unknown_unresolved, usual_care.

1 supporting study lacks usable structured population information.

4 supporting studies have high, serious, critical, unclear, or unavailable risk-of-bias information.

Structured population data were available for 8 of 8 supporting studies. 7 studies described participants with type 2 diabetes. 7 studies described adult participants.

Evidence uses heterogeneous comparison contexts: active_comparator, baseline_within_group, placebo.

1 supporting study has high, serious, critical, unclear, or unavailable risk-of-bias information.

Structured population data were available for 4 of 4 supporting studies. 4 studies described participants with type 1 diabetes. 2 studies described adult participants.

Structured population data were available for 8 of 8 supporting studies. 6 studies described participants with type 2 diabetes. 7 studies described adult participants.

Evidence uses heterogeneous comparison contexts: active_comparator, unknown_unresolved, usual_care.

Structured population data were available for 8 of 8 supporting studies. Diabetes type was heterogeneous: 4 studies with type 2 diabetes, 1 studies with type 1 diabetes. Age groups were heterogeneous: 4 studies with adult participants, 1 studies with youth participants.

Evidence uses heterogeneous comparison contexts: active_comparator, placebo, usual_care.

5 of 8 studies with duration data have follow-up of 12 weeks or less.

Structured population data were available for 3 of 3 supporting studies. 3 studies described participants with type 2 diabetes. 3 studies described adult participants.

3 of 3 studies with duration data have follow-up of 12 weeks or less.

Evidence uses heterogeneous comparison contexts: active_comparator, placebo.

Evidence uses heterogeneous comparison contexts: active_comparator, baseline_within_group.

Structured population data were available for 3 of 3 supporting studies. Diabetes type was heterogeneous: 1 studies with type 1 diabetes, 1 studies with type 2 diabetes. 2 studies described adult participants.

Structured population data were available for 13 of 13 supporting studies. 11 studies described participants with type 2 diabetes. 12 studies described adult participants.

4 relevant studies have unresolved authoritative design evidence and do not contribute to design-specific or RoB-specific claims.

Evidence uses heterogeneous comparison contexts: active_comparator, baseline_within_group, usual_care.

Evidence uses heterogeneous comparison contexts: unknown_unresolved, usual_care.

Structured population data were available for 3 of 3 supporting studies. Diabetes type was heterogeneous: 2 studies with type 2 diabetes, 1 studies with type 1 diabetes. Age groups were heterogeneous: 2 studies with adult participants, 1 studies with youth participants.

Structured population data were available for 12 of 12 supporting studies. Diabetes type was heterogeneous: 9 studies with type 2 diabetes, 1 studies with type 1 diabetes. 12 studies described adult participants.

9 supporting studies have high, serious, critical, unclear, or unavailable risk-of-bias information.

Structured population data were available for 5 of 5 supporting studies. 5 studies described participants with type 2 diabetes. 4 studies described adult participants.

Structured population data were available for 3 of 3 supporting studies. 2 studies described participants with type 2 diabetes. 2 studies described adult participants.

Structured population data were available for 2 of 3 supporting studies. 2 studies described participants with type 2 diabetes. 2 studies described adult participants.

Evidence uses heterogeneous comparison contexts: active_comparator, placebo, unknown_unresolved.

Structured population data were available for 10 of 10 supporting studies. Diabetes type was heterogeneous: 8 studies with type 2 diabetes, 2 studies with type 1 diabetes. Age groups were heterogeneous: 8 studies with adult participants, 1 studies with youth participants.

Evidence uses heterogeneous comparison contexts: active_comparator, other, usual_care.

3 studies contain conflicting p-value and significance fields; those significance claims are suppressed.

Structured population data were available for 4 of 4 supporting studies. 2 studies described participants with type 2 diabetes. 4 studies described adult participants.

Evidence uses heterogeneous comparison contexts: other, usual_care.

2 of 4 studies with duration data have follow-up of 12 weeks or less.

Structured population data were available for 4 of 4 supporting studies. Diabetes type was heterogeneous: 2 studies with type 2 diabetes, 1 studies with type 1 diabetes. 4 studies described adult participants.

Structured population data were available for 5 of 5 supporting studies. 5 studies described participants with type 2 diabetes. 5 studies described adult participants.

Structured population data were available for 11 of 11 supporting studies. 10 studies described participants with type 2 diabetes. 11 studies described adult participants.

Structured population data were available for 6 of 6 supporting studies. 6 studies described participants with type 2 diabetes. 6 studies described adult participants.

Evidence uses heterogeneous comparison contexts: active_comparator, baseline_within_group, unknown_unresolved, usual_care.

Structured population data were available for 7 of 7 supporting studies. Diabetes type was heterogeneous: 2 studies with type 2 diabetes, 1 studies with type 1 diabetes. 5 studies described adult participants.

Structured population data were available for 5 of 5 supporting studies. 3 studies described participants with type 2 diabetes. 4 studies described adult participants.

Structured population data were available for 5 of 5 supporting studies. Diabetes type was heterogeneous: 4 studies with type 2 diabetes, 1 studies with type 1 diabetes. 3 studies described adult participants.

Evidence uses heterogeneous comparison contexts: baseline_within_group, placebo, usual_care.

Low-carbohydrate diet × HbA1c

Available supporting studies

Dietary interventions improve glycemic control in pre-diabetic patients

Online education improves glycemic control in type 2 diabetes management

Weight loss improves heart rate variability in type 2 diabetes