RESUMO

BACKGROUND: It is unknown whether vegetarian diets (VDs) may improve outcomes in people with overweight and obesity. OBJECTIVE: To systematically assess the effects of VDs vs. omnivore diets on anthropometric, metabolic, and blood pressure outcomes in people with overweight and obesity. METHODS: We searched for randomized controlled trials (RCTs) in EMBASE, PubMed, Web of Science, and Scopus until February 2, 2022. Primary outcomes were anthropometric risk factors (weight, body mass index [BMI], waist circumference [WC], hip circumference [HC], and body fat percentage). Secondary outcomes were metabolic risk factors (fasting serum glucose, HbA1c, insulin levels) and blood pressure (systolic blood pressure [SBP], diastolic blood pressure [DBP]). Random-effects meta-analyses were performed and effects were expressed as mean difference (MD) and their 95% confidence intervals (CI). The quality of evidence was assessed using GRADE methods. RESULTS: Nine RCTs (n = 1628) were included. VDs decreased weight (MD -3.60 kg, 95%CI -4.75 to -2.46) and glucose (MD -10.64 mg/dL, 95%CI -15.77 to -5.51), but did not decrease WC (MD -3.00 cm, 95%CI -6.20 to 0.20), BMI (MD -0.87 kg/m2, 95%CI -1.80 to 0.06), or HC (MD: -0.86 cm, 95%CI -3.46 to 1.74). VDs did not decrease HbA1c (MD -0.40%, 95%CI -0.89 to 0.10), insulin (MD -3.83 mU/L, 95%CI -8.06 to 0.40), SBP (MD -0.25 mmHg, 95%CI -2.58 to 2.07), or DBP (MD -1.57 mmHg, 95%CI -3.93 to 0.78). Subgroup analyses by type of VD (four RCTs evaluated lacto-ovo-vegetarian diets and five RCTs vegan diets) showed similar results to the main analyses. QoE was very low for most of the outcomes. CONCLUSIONS: In comparison to an omnivorous diet, VDs may reduce weight and glucose, but not blood pressure or other metabolic or anthropometric outcomes. However, the QoE was mostly very low. Larger RCTs are still needed to evaluate the effects of VD on anthropometric, metabolic factors, and blood pressure in people with overweight and obesity.

Assuntos

Insulinas , Sobrepeso , Humanos , Hemoglobinas Glicadas , Ensaios Clínicos Controlados Aleatórios como Assunto , Obesidade , Dieta Vegetariana , Glucose

RESUMO

Objective: We systematically assessed the efficacy of liraglutide in non-diabetic obese adults. Methods: Six databases were searched up to July 2021 for randomized controlled trials (RCTs) assessing liraglutide versus placebo in obese adults. Primary outcomes were body weight and body mass index (BMI). Secondary outcomes were treatment-emergent adverse events (TEAEs), hypoglycemic episodes, HbA1c, and blood pressure. Effect measures were risk ratio (RR) or mean difference (MD) with their confidence interval (95%CI). Random-effects models and inverse variance meta-analyses were used. Quality of evidence was assessed using GRADE. Results: Twelve RCTs (n = 8249) were included. In comparison to placebo, liraglutide reduced body weight (MD −3.35 kg; 95%CI −4.65 to −2.05; p < 0.0001), and BMI (MD −1.45 kg/m2; 95%CI −1.98 to −0.91; p < 0.0001). Liraglutide did not reduce TEAEs (RR 1.08; 95%CI 0.92 to 1.27; p = 0.25), and Hb1Ac (MD −0.76%; 95%CI −2.24 to 0.72; p = 0.31). Furthermore, it did not increase hypoglycemic episodes (RR 2.01; 95%CI 0.37 to 11.02; p = 0.28). Finally, liraglutide reduced systolic blood pressure (MD −3.07 mmHg; 95%CI −3.66 to −2.48; p < 0.0001) and diastolic blood pressure (MD −1.01 mmHg; 95%CI −1.55 to −0.47; p = 0.0003). Seven RCTs had a high risk of bias. Subgroup analyses by length of treatment and doses had effects similar to the overall analyses. Quality of evidence was low or very low for most outcomes. Conclusions: In non-diabetic obese adults, liraglutide reduced body weight, BMI and blood pressure in comparison to placebo. Adverse events, Hb1Ac levels and hypoglycemic episodes were not different than placebo.