The Effect of Processing on the Measured Energy Value of Almonds in the Human Diet

Study Overview
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Brief Summary
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The objective of this study is to measure the effect of processing (roasting, slicing, or grinding) on the energy value of almonds in the human diet and study molecular mechanisms that may help explain the beneficial health effects of almonds.

Detailed Description
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The metabolizable energy values, or Atwater general factors, for protein, fat, and carbohydrate are commonly used to calculate the metabolizable energy of a diet. Atwater factors are based on average values of mixed diets and are not exact; thus, using these values could introduce an error in the calculated metabolizable energy of a particular food due to differences in chemical structure and availability. Studies have demonstrated that Atwater general factors overestimate the energy derived from protein and fat, as well as the measured metabolizable energy of mixed diets, particularly those that are high in dietary fiber. Studies are lacking, however, that examine how different processing methods affect the metabolizable energy of a food due to differences in chemical structure and availability.

Official Title
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Macronutrient Absorption From Almonds: The Effect of Processing on the Measured Energy Value of Almonds in the Human Diet

Conditions
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Healthy, Focus: Effect of Processing on Energy Value of Almonds

Intervention / Treatment
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* Other: Control
* Other: Whole Almonds
* Other: Roasted Whole Almonds
* Other: Diced Almonds
* Other: Almond Butter


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 25 to 75 years at beginning of study BMI between 20 and 38 kg/m2 Fasting glucose < 126 mg/dl Blood pressure < 160/100 (controlled with certain medications) Fasting total blood cholesterol < 280 mg/dl Fasting triglycerides < 300 mg/dl Exclusion Criteria: Presence of kidney disease, liver disease, gout, hyperthyroidism, untreated or unstable hypothyroidism, certain cancers, gastrointestinal disease, pancreatic disease, other metabolic diseases, or malabsorption syndromes Women who have given birth during the previous 12 months Pregnant women or women who plan to become pregnant or become pregnant during the study Lactating women Type 2 diabetes requiring the use of oral antidiabetic agents or insulin History of bariatric or certain other surgeries related to weight control Smokers or other tobacco users (during 6 months prior to the start of the study) History of eating disorders or other dietary patterns which are not consistent with the dietary intervention (e.g., vegetarians, very low fat diets, high protein diets) Volunteers who have lost 10% of body weight within the last 12 months Known (self-reported) allergy or adverse reaction to almonds or other nuts Unable or unwilling to give informed consent or communicate with study staff Self-report of alcohol or substance abuse within the past 12 months and/or current acute treatment or rehabilitation program for these problems (long-term participation in Alcoholics Anonymous is not an exclusion) Other medical, psychiatric, or behavioral factors that in the judgment of the Principal Investigator may interfere with study participation or the ability to follow the intervention protocol

Ages Eligible for Study
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Minimum Age: 25 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Control<br>Diet will consist of a controlled diet without almonds for 3 weeks. | Other: Control<br>* Controlled diet for 3 weeks with 0 servings/day of almonds.<br>|
| Experimental: Whole Almonds<br>Diet will consist of a controlled diet with whole almonds for 3 weeks. | Other: Whole Almonds<br>* Controlled diet for 3 weeks with 1.5 servings/day of whole, natural almonds.<br>|
| Experimental: Roasted Whole Almonds<br>Diet will consist of a controlled diet with roasted whole almonds for 3 weeks. | Other: Roasted Whole Almonds<br>* Controlled diet for 3 weeks with 1.5 servings/day of roasted whole almonds.<br>|
| Experimental: Diced Almonds<br>Diet will consist of a controlled diet with diced almonds for 3 weeks. | Other: Diced Almonds<br>* Controlled diet for 3 weeks with 1.5 servings/day of diced almonds.<br>|
| Experimental: Almond Butter<br>Diet will consist of a controlled diet with almond butter for 3 weeks. | Other: Almond Butter<br>* Controlled diet for 3 weeks with 1.5 servings/day of almond butter.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Metabolizable Energy | The metabolizable energy value of almonds and almond butter will be calculated based on the chemical composition and energy content of the consumed diet and excreta. | End of each 3-week diet period | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Digestibility | Fat, protein, and fiber digestibility will be calculated and the effect of almond on nutrient digestibility will be assessed. | End of each 3-week diet period | 
| Almond nutrient metabolism | Blood and urine will be analyzed for appearance of almond nutrients and their metabolites. | End of each 3-week diet period | 
| Biomarkers of cardiovascular disease | Blood will be analyzed for biomarkers of risk for cardiovascular disease and cancer such as oxidative stress and inflammatory markers. | End of each 3-week diet period |