Almond Consumption and Glycemia
Condition: Glucose Intolerance; Appetite Disorders; Glucose Metabolism Disorders (Including Diabetes Mellitus); Lipid Metabolism Disorder
MeSH terms: Metabolic Diseases; Glucose Metabolism Disorders; Glucose Intolerance; Lipid Metabolism Disorders; Feeding and Eating Disorders
Study type: Interventional

Summary: 
      This study will examine the effects of almonds consumed by adults with different body fat
      distributions on indices of carbohydrate and lipid metabolism.
    

Detailed description: 
      There is considerable evidence supporting a causal role for truncal visceral fat depots in
      glucose dysregulation. Individuals with large visceral fat depots have impaired suppression
      of free fatty acid release in response to insulin, elevated triglycerides and low
      concentrations of high density lipoprotein cholesterol. The high free fatty acid
      concentration may induce insulin resistance in the muscle and liver. There is more recent
      evidence that truncal subcutaneous fat depots are also problematic, though this literature is
      mixed. In contrast, gluteo-femoral fat depots have not been implicated in insulin resistance
      and dysregulation of carbohydrate metabolism. Failure to account for differences in the
      contributions of these depots will add noise to measurements of dietary interventions to
      mitigate glucose dysregulation. Previous studies have reported evidence indicating acute and
      chronic consumption of almonds improves glycemia. Acute effects are important indicators of
      health benefit, but longer-term trials, ones permitting identification of the effects of a
      dietary intervention on HbA1c, are more telling and clinically relevant. To more definitively
      establish the association between almond consumption and improved carbohydrate metabolism, we
      propose a six-month trial that contrasts the effects of almond consumption at optimal times
      of the day versus consumption of low nutrient dense snack foods on indices of carbohydrate
      metabolism, food intake and appetite in adults characterized by three distinct fat depots.

      Participants will consume either almonds, or no nuts every day for 6 months. At baseline,
      participants will be weighed and undergo a DEXA scan to determine body fat composition and
      will be assigned a group. Blood will also be collected fasted and at stipulated times in
      response to a meal tolerance test to measure insulin, glucose, C-peptide, HbA1c, lipid panel,
      gut peptides, and compliance to the diet. Participants will be given links to complete
      appetite ratings and record food intake. Participants will report to the lab every two weeks
      to be weighed, and get a resupply of almonds (if in the almond group). At the two-week mark
      on months 2 and 4, participants will be weighed, blood will be taken to assess compliance to
      the diet, and links will be given to complete appetite ratings and record food intake. At
      month 6, all measurements from baseline will be repeated.
    

Intervention name(s): Almonds; Control (no nuts)
Intervention type(s): Other; Other
Intervention description(s): Participants will consume almonds everyday for 6 months.; Participants will not be permited to consume any nuts for 6 months.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Basic Science