Meta-analyses of the Effect of Tree Nuts on Glycemic Control and Features of the Metabolic Syndrome

NCT01630980 | Completed

• 1 other identifier: INC 2012 KRS
• Study Type: observational
• Target: 1
• Locations: 1 country
• Sites: 1

Brief Summary

Tree nuts (almonds, Brazil nuts, cashews, hazelnuts, macadamia nuts, pecans, pine nuts, pistachios and walnuts) are an important source of unsaturated fatty acids, vegetable protein, and fibre, as well as minerals, vitamins, and phytonutrients. Although heart disease risk reduction claims for nuts have been permitted in the U.S. and general dietary guidelines and recommendations from heart associations recommend the consumption of nuts for heart protection, diabetes associations have not addressed nuts in their most recent recommendations. This omission is despite heart disease being a major cause of death in diabetes. There remains insufficient information on the usefulness of these foods in diabetes. To improve evidence-based guidance for tree nut recommendations, the investigators propose to conduct a systematic review of the effect of tree nuts on diabetes control and features of the metabolic syndrome. The systematic review process allows the combining of the results from many small studies in order to arrive at a pooled estimate, similar to a weighted average, of the true effect. The investigators will be able to explore whether eating tree nuts has different effects between men and women, in different age groups and background disease states, and whether or not the effect of tree nuts depends on the dose and background diet. The findings of this proposed knowledge synthesis will help improve the health of Canadians through informing diabetes association recommendations and heart association recommendations where they relate to diabetes.

Conditions

Diabetes; Prediabetes; Dysglycemia; Overweight; Obesity; Dyslipidemia; Hypertension; Metabolic Syndrome; Cardiovascular Diseases

Keywords

Systematic review and meta-analysis; Evidence-based medicine (EBM); Evidence-based nutrition (EBN); Clinical practice guidelines; Clinical trials; Tree nuts; Cardiometabolic risk factors; Triglycerides; Cholesterol; Glycemic control; Insulin resistance; Body weight; Blood pressure

Outcome Measures

Primary Outcomes (2)

• Glycemic control measures

  Glycated blood proteins (HbA1c, total glycated hemoglobin, fructosamine, glycated albumin), fasting glucose, fasting insulin, and the homeostasis model assessment of insulin resistance (HOMA-IR)

  Up to 1.5-years

• Metabolic syndrome measures

  Harmonized metabolic syndrome diagnostic measures (waist circumference, TG, HDL-C, blood pressure, fasting glucose)

  Up to 1.5-years

Interventions

Tree nuts OTHER

Almonds, Brazil nuts, cashews, hazelnuts, macadamia nuts, pecans, pine nuts, pistachios and walnuts in whole, meal, or flour form

Eligibility Criteria

• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)
• Sampling Method: Probability Sample

Study Population

Varied

You may qualify if:

• Dietary trials in humans
• Randomized treatment allocation
• \>=3-weeks
• Suitable control (i.e. isocaloric exchange of other dietary components for tree nuts)
• viable endpoint data

You may not qualify if:

• Non-human studies
• Nonrandomized treatment allocation
• weeks
• Lack of a suitable control (non-isocaloric)
• no viable endpoint data

Sponsors & Collaborators

• John Sievenpiper: lead
• The International Tree Nut Council Nutrition Research & Education Foundation: collaborator
• Canada Research Chairs Endowment of the Federal Government of Canada: collaborator
• Canadian Institutes of Health Research (CIHR): collaborator

Study Sites (1)

The Toronto 3D (Diet, Digestive tract and Disease) Knowledge Synthesis and Clinical Trials Unit, Clinical Nutrition and Risk Factor Modification Centre, St. Micheal's Hospital

Toronto, Ontario, M5C 2T2, Canada

Location

Related Publications (3)

• Jenkins DJ, Kendall CW, Banach MS, Srichaikul K, Vidgen E, Mitchell S, Parker T, Nishi S, Bashyam B, de Souza R, Ireland C, Josse RG. Nuts as a replacement for carbohydrates in the diabetic diet. Diabetes Care. 2011 Aug;34(8):1706-11. doi: 10.2337/dc11-0338. Epub 2011 Jun 29.

  PMID: 21715526 BACKGROUND

• Blanco Mejia S, Kendall CW, Viguiliouk E, Augustin LS, Ha V, Cozma AI, Mirrahimi A, Maroleanu A, Chiavaroli L, Leiter LA, de Souza RJ, Jenkins DJ, Sievenpiper JL. Effect of tree nuts on metabolic syndrome criteria: a systematic review and meta-analysis of randomised controlled trials. BMJ Open. 2014 Jul 29;4(7):e004660. doi: 10.1136/bmjopen-2013-004660.

  PMID: 25074070 RESULT

• Viguiliouk E, Kendall CW, Blanco Mejia S, Cozma AI, Ha V, Mirrahimi A, Jayalath VH, Augustin LS, Chiavaroli L, Leiter LA, de Souza RJ, Jenkins DJ, Sievenpiper JL. Effect of tree nuts on glycemic control in diabetes: a systematic review and meta-analysis of randomized controlled dietary trials. PLoS One. 2014 Jul 30;9(7):e103376. doi: 10.1371/journal.pone.0103376. eCollection 2014.

  PMID: 25076495 RESULT

MeSH Terms

Conditions

Diabetes Mellitus; Prediabetic State; Overweight; Obesity; Dyslipidemias; Hypertension; Metabolic Syndrome; Cardiovascular Diseases; Insulin Resistance; Body Weight

Condition Hierarchy (Ancestors)

Glucose Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases; Endocrine System Diseases; Overnutrition; Nutrition Disorders; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Lipid Metabolism Disorders; Vascular Diseases; Hyperinsulinism

Study Officials

• John L Sievenpiper, MD, PhD

  Department of Pathology and Molecular Medicine, McMaster University and Clinical Nutrition and Risk Factor Modification Centre, St. Michael's Hospital

  STUDY DIRECTOR

• Russell J de Souza, ScD, RD

  Department of Epidemiology and Biostatistics, McMaster University and Clinical Nutrition and Risk Factor Modification Centre, St. Michael's Hospital

  STUDY DIRECTOR

• Cyril WC Kendall, PhD

  Department of Nutritional Sciences and Medicine, University of Toronto and Clinical Nutrition and Risk Factor Modification Centre, St. Michael's Hospital

  PRINCIPAL INVESTIGATOR

• David JA Jenkins, MD, PhD, DSc

  Department of Nutritional Sciences and Medicine, University of Toronto and Clinical Nutrition and Risk Factor Modification Centre, St. Michael's Hospital

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Knowledge Synthesis Lead

Study Record Dates

• First Submitted: May 18, 2012
• First Posted: June 28, 2012
• Study Start: May 1, 2012
• Primary Completion: May 1, 2014
• Study Completion: May 1, 2014
• Last Updated: May 27, 2015

Record last verified: 2015-05

Locations

CA (1)