Table 5 Grading of Evidence for associations between dietary intakes ( ≥ 24 months and beyond) and weight loss (up to twelve-years) (13 studies)*.
Macronutrient Composition | Food Pattern | ||||
|---|---|---|---|---|---|
Carbohydrate | Protein | Fat | Fruit and Vegetables | All non-fruit or vegetable core food groups | |
Study Findings | No Association (11 studies, total N = 1305, up to 12-years) [23, 26, 33, 35, 39, 43,44,45, 50, 51, 56] Level II: 1 LR study [43] (N = 355) Level III: 4 LR studies [23, 35, 39, 50], 4 AR studies [26, 33, 44, 51], 1 HR study [56] (N = 843) Level IV: 1 AR study [45] (N = 107) | No Association (12 studies, total N = 1402, up to 12-years) [23, 26, 33, 35, 39, 43,44,45, 50, 51, 56, 57] Level II: 1 LR study [43] (N = 355) Level III: 4 LR studies [23, 35, 39, 50], 4 AR studies [26, 33, 44, 51], 1 HR study [56] (N = 843) | No Association (11 studies, total N = 1305, up to 12-years) [23, 26, 33, 35, 39, 43,44,45, 50, 51, 56] Level II: 1 LR study [43] (N = 355) Level III: 4 LR studies [23, 35, 39, 50], 4 AR studies [26, 33, 44, 51], 1 HR study [56] (N = 843) Level IV: 1 AR study [45] (N = 107) | Positive Association (1 study, total N = 30, up to 3-years) Level II: 1 HR study [47] No Association (3 studies, total N = 244, up to 9-years) Level III: 1 LR study [23], 1 AR study [33] (N = 147) Level IV: 1 AR study [57] (N = 97) | No Association (2 studies, total N = 147, up to 5-years) |
GRADING OF EVIDENCE | |||||
Evidence Statement | Weight loss is not associated with macronutrient composition at >24 months post-bariatric surgery. | Weight loss is not associated with core food group patterns at >24 months post-bariatric surgery. | |||
Evidence Base | B – Good. >2 Level III (cohort) studies with low risk of bias. Study findings are derived from cohort studies only. | C – Satisfactory. 1-2 Level III (cohort) studies with low risk of bias. Though evidence base included one interventional study, it was one that was of an increased risk of bias with small sample size. | |||
Consistencies | A – Excellent 11 out of 11 studies demonstrated no associations between weight loss and carbohydrate intake. | A – Excellent 12 out of 12 studies demonstrated no associations between weight loss and protein intake. | A – Excellent 11 out of 11 studies demonstrated no associations between weight loss and fat intake. | B – Good. 3 out of 4 studies demonstrated no associations between weight loss and fruit/vegetable intakes. Co-variables from study design have prevented attribution of effect to diet intakes alone in the single study that demonstrated an association. | A – Excellent 2 out of 2 studies demonstrated no associations between weight loss and non-fruit/vegetable intakes. |
Clinical Impact | B – Good. Study findings highly consistent regardless of participant characteristics, study design, risk of bias, outcome measures or duration of follow-up. | ||||
Generalizability | B – Good. All studies in adults at least one-year post-bariatric surgery in an outpatient setting. | ||||
Applicability | B – Good. Most studies were conducted with population from the Western context like the Australian bariatric context. | ||||
RECOMMENDATION | GRADE OF RECOMMENDTION | ||||
Individualized diets with flexibility on macronutrient and food group composition can be recommended at two years or more post-bariatric surgery, as no composition or patterns showed associations with weight loss. | B Body of evidence can be trusted to guide practice in most situations. | ||||
