We are updating the design of this site. Learn more.
Show more
ClinicalTrials.gov
ClinicalTrials.gov Menu

Effects of Almond Intake on Atherogenic Lipoprotein Particles

This study has been completed.
Sponsor:
ClinicalTrials.gov Identifier:
NCT01792648
First Posted: February 15, 2013
Last Update Posted: November 2, 2017
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
Collaborator:
Almond Board of California
Information provided by (Responsible Party):
Children's Hospital & Research Center Oakland
  Purpose

Increased abdominal adiposity is a key feature of metabolic syndrome, which describes a cluster of cardiovascular disease (CVD) risk factors that also includes insulin resistance, high blood pressure and an atherogenic lipoprotein phenotype characterized by increased plasma triglycerides, low HDL-C, and increased levels of small LDL particles. While lifestyle intervention remains the cornerstone for managing obesity and metabolic syndrome, the optimal dietary macronutrient distribution for improving blood lipids and CVD risk remains a topic of controversy. While both low carbohydrate diets and weight reduction are effective for managing atherogenic dyslipidemia, long-term compliance is low, and it becomes imperative to identify alternative dietary approaches.

Increased consumption of almonds has been shown to lower LDL-C, an effect that exceeds that predicted from changes in fatty acid intake. However, although LDL-C lowering by almonds has been demonstrated in patients with diabetes, there have been no trials in non-diabetic patients with abdominal obesity. Moreover, there is limited information of the effects of almond intake on LDL particle subclasses.

The overall objective of the present study is to determine whether lipoprotein measures of CVD risk in individuals with increased abdominal adiposity are reduced by almond supplementation in a diet with overall macronutrient content that conforms to current guidelines. Our main hypothesis is that in these individuals, almond consumption can reduce levels of small and medium LDL particles without the need to restrict dietary carbohydrates to levels below those currently recommended.

This hypothesis will be tested by comparing the lipoprotein effects of an almond-supplemented diet (20%E) with those of two reference diets that do not contain almond products: one with similar content of carbohydrate, protein, and fat (standard reference), and the other in which carbohydrate content is reduced by substitution of protein and monounsaturated fat (low-carbohydrate reference).

We will provide the diets for 3 weeks each in a randomized 3-period crossover design to 40 individuals with increased abdominal adiposity. We will test whether the almond supplemented diet will result in lower levels of lipoprotein measures of CVD risk, specifically LDL-C and small and medium LDL particles, compared to either the standard or low-carbohydrate reference diets.


Condition Intervention
Dyslipidemia Obesity, Abdominal Other: Standard reference diet Other: Almond supplemented diet Other: Low carbohydrate reference diet

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single (Investigator)
Primary Purpose: Treatment
Official Title: Effects of Almond Intake on Atherogenic Lipoprotein Particles in Individuals With Increased Abdominal Adiposity

Further study details as provided by Children's Hospital & Research Center Oakland:

Primary Outcome Measures:
  • Change in Total and LDL cholesterol [ Time Frame: 3 weeks, 8 weeks, 13 weeks ]
    Change in total and LDL cholesterol between each of the 3 test diets

  • Change in small and medium LDL particles [ Time Frame: 3 weeks, 8 weeks, and 13 weeks ]
    Change in small and medium LDL particles between each of the 3 test diets

  • Change in apolipoprotein B [ Time Frame: 3 weeks, 8 week, 13 weeks ]
    Change in apolipoprotein B between each of the 3 test diets


Secondary Outcome Measures:
  • Change in total/HDL-cholesterol ratio [ Time Frame: 3 weeks, 8 weeks, 13 weeks ]
    Change in total/HDL-cholesterol ratio between each of the 3 test diets

  • Change in LDL peak particle diameter [ Time Frame: 3 weeks, 8 week, 13 weeks ]
    Change in LDL peak particle diameter between each of the 3 test diets

  • Change in plasma triglycerides [ Time Frame: 3 weeks, 8 weeks, 13 weeks ]
    Change in plasma triglycerides between each of the 3 test diets

  • Change in HDL-cholesterol [ Time Frame: 3 weeks, 8 weeks, 13 weeks ]
    Change in HDL-cholesterol between each of the 3 test diets

  • Change in large HDL particles [ Time Frame: 3 weeks, 8 weeks, 13 weeks ]
    Change in large HDL particles between each of the 3 test diets

  • Change in apolipoprotein AI [ Time Frame: 3 weeks, 8 weeks, 13 weeks ]
    Change in apolipoprotein AI between each of the 3 test diets

  • Change in HOMA-IR [ Time Frame: 3 weeks, 8 weeks, 13 weeks ]
    Change in homeostatic model assessment insulin resistance (HOMA-IR) after each of the 3 test diets


Enrollment: 24
Study Start Date: April 2013
Study Completion Date: April 2016
Primary Completion Date: February 2016 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Standard Reference Diet Other: Standard reference diet
50% energy as carbohydrate, 15% energy as protein, 35% energy as total fat
Experimental: Almond Supplemented Diet Other: Almond supplemented diet
50% energy as carbohydrate, 15% energy as protein, 35% energy as total fat, 20% energy from almonds
Active Comparator: Low Carbohydrate Reference Diet Other: Low carbohydrate reference diet
26% energy from carbohydrate, 29% energy from protein, 45% energy from total fat

  Eligibility

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.


Ages Eligible for Study:   20 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Age 20 or older
  • Increased abdominal adiposity as defined by waist circumference ≥102 for men or ≥88 for women.
  • Fasting blood sugar (FBS) < 126 mg/dl
  • Weight stable for > 3 months.

Exclusion Criteria:

  • History of coronary heart disease, cerebrovascular disease, peripheral vascular disease, bleeding disorder, liver or renal disease, diabetes, lung disease, HIV, or cancer (other than skin cancer) in the last 5 years.
  • Taking hormones or drugs known to affect lipid metabolism or blood pressure.
  • Systolic blood pressure > 160 mm Hg and diastolic blood pressure > 95 mm Hg.
  • Body mass index (BMI) > 38 kg/m2
  • User of nicotine products or recreational drugs
  • Refusal to abstain from alcohol or dietary supplements during the study.
  • Total- and LDL-C > 95th percentile for sex and age.
  • Fasting triglycerides > 50mg/dl and > 500 mg/dl
  • Abnormal thyroid stimulating hormone (TSH) levels.
  • Pregnant or breast-feeding
  Contacts and Locations
Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01792648


Locations
United States, California
Cholesterol Research Center
Berkeley, California, United States, 94705
Sponsors and Collaborators
Children's Hospital & Research Center Oakland
Almond Board of California
Investigators
Principal Investigator: Ronald M Krauss, MD Children's Hospital & Research Center Oakland
  More Information

Responsible Party: Children's Hospital & Research Center Oakland
ClinicalTrials.gov Identifier: NCT01792648     History of Changes
Other Study ID Numbers: MM2222
First Submitted: April 26, 2012
First Posted: February 15, 2013
Last Update Posted: November 2, 2017
Last Verified: October 2017

Keywords provided by Children's Hospital & Research Center Oakland:
Almond
Carbohydrate
Diet
Cholesterol

Additional relevant MeSH terms:
Dyslipidemias
Obesity, Abdominal
Lipid Metabolism Disorders
Metabolic Diseases
Obesity
Overnutrition
Nutrition Disorders