Metabolic Effects of Monounsaturated Fatty Acid-Enriched Diets Compared With Carbohydrate or Polyunsaturated Fatty Acid-Enriched Diets in Patients With Type 2 Diabetes: A Systematic Review and Meta-analysis of Randomized Controlled Trials

Diabetes Care. 2016 Aug;39(8):1448-57. doi: 10.2337/dc16-0513.

Abstract

Objective: Dietary interventions in patients with type 2 diabetes (T2D) are important for preventing long-term complications. Although a healthy diet is crucial, there is still uncertainty about the optimal macronutrient composition. We performed a meta-analysis comparing diets high in cis-monounsaturated fatty acids (MUFA) to diets high in carbohydrates (CHO) or in polyunsaturated fatty acids (PUFA) on metabolic risk factors in patients with T2D.

Research design and methods: We systematically reviewed PubMed, MEDLINE, and Cochrane databases and prior systematic reviews and meta-analyses to identify interventions assessing HbA1c, fasting plasma glucose and insulin, LDL and HDL cholesterol, triglycerides, body weight, or systolic/diastolic blood pressure. Meta-analyses were conducted using both fixed- and random-effects models to calculate the weighted mean difference (WMD) and 95% CI.

Results: We identified 24 studies totaling 1,460 participants comparing high-MUFA to high-CHO diets and 4 studies totaling 44 participants comparing high-MUFA to high-PUFA diets. When comparing high-MUFA to high-CHO diets, there were significant reductions in fasting plasma glucose (WMD -0.57 mmol/L [95% CI -0.76, -0.39]), triglycerides (-0.31 mmol/L [-0.44, -0.18]), body weight (-1.56 kg [-2.89, -0.23]), and systolic blood pressure (-2.31 mmHg [-4.13, -0.49]) along with significant increases in HDL cholesterol (0.06 mmol/L [0.02, 0.10]). When high-MUFA diets were compared with high-PUFA diets, there was a significant reduction in fasting plasma glucose (-0.87 mmol/L [-1.67, -0.07]). All of the outcomes had low to medium levels of heterogeneity, ranging from 0.0 to 69.5% for diastolic blood pressure (Phet = 0.011).

Conclusions: Our meta-analysis provides evidence that consuming diets high in MUFA can improve metabolic risk factors among patients with T2D.

Publication types

  • Meta-Analysis
  • Review
  • Systematic Review

MeSH terms

  • Blood Glucose / metabolism
  • Blood Pressure
  • Body Weight
  • Cholesterol, HDL / blood
  • Cholesterol, LDL / blood
  • Diabetes Mellitus, Type 2 / blood
  • Diabetes Mellitus, Type 2 / diet therapy*
  • Diet*
  • Diet, High-Fat
  • Dietary Carbohydrates / administration & dosage
  • Fatty Acids, Monounsaturated / administration & dosage*
  • Fatty Acids, Unsaturated / administration & dosage*
  • Glycated Hemoglobin A / metabolism
  • Humans
  • Insulin / blood
  • Randomized Controlled Trials as Topic
  • Triglycerides / blood

Substances

  • Blood Glucose
  • Cholesterol, HDL
  • Cholesterol, LDL
  • Dietary Carbohydrates
  • Fatty Acids, Monounsaturated
  • Fatty Acids, Unsaturated
  • Glycated Hemoglobin A
  • Insulin
  • Triglycerides