The Effect of Pecans on Biomarkers of Risk for Cardiovascular Disease and Diabetes

Study Overview
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Brief Summary
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The objective of this randomized, controlled feeding study is to investigate the potential health benefits of a pecan-containing diet. The investigators hypothesize the chronic consumption of pecans will improve an array of biomarkers related to cardiovascular disease and type 2 diabetes risk, including indices of oxidative stress, antioxidant activity, inflammation, endothelial function, and insulin resistance when compared with a control diet that is absent nuts.

Official Title
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The Effect of Pecans on Biomarkers of Risk for Cardiovascular Disease and Diabetes: A Controlled Feeding Trial in Overweight/Obese Adults With Central Adiposity

Conditions
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Cardiovascular Disease Risk, Type 2 Diabetes Risk

Intervention / Treatment
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* Other: Pecan-containing diet
* Other: Nut-free diet


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Men & postmenopausal women, age 50 years and over BMI 25-35 kg/m2 Waist/hip >0.8 for women and >0.9 for men Blood pressure between 120/80 and 159/99 Exclusion Criteria: Cigarette smoking and/or nicotine replacement use Individuals taking estrogen Use of cholesterol-lowering medications Use of blood pressure-lowering medications Regular use of any stomach acid-lowering medications, laxatives (including fiber supplements) or anti-diarrheal medications (prescription or over-the-counter [OTC]) Cardiovascular (heart) disease Gastrointestinal disease Kidney disease Endocrine disease: including diabetes, unstable thyroid disease Autoimmune disease: including rheumatoid arthritis, gout, lupus, HIV Active treatment for any type of cancer, except basal cell carcinoma, within 1 year prior to study admission Systolic blood pressure > 159 mmHg and/or diastolic blood pressure > 99 mmHg Regular use of oral or injectable steroids Gain or loss of > 10% of body weight within previous 3 months; unwillingness to maintain your weight Regular daily intake of ≥ 2 alcoholic drinks Vegetarians Current allergy to any kind of nut Dietary supplement use, including those containing any vitamins, minerals, herbs, plant concentrates (including garlic, gingko, St. John's wort) homeopathic remedies, probiotics, or fish oil (including cod liver oil), for one month prior to study admission

Ages Eligible for Study
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Minimum Age: 50 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

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Pecan-containing diet<br>Test diet containing 1.5 oz pecans/2000 kcal/day for 28 days | Other: Pecan-containing diet<br> <br> * Other names: Isocaloric diet containing 1.5 oz pecans per 2000 kcal per day for 28 days;|
| Placebo Comparator: Nut-free diet<br>Placebo diet containing no nuts or nut products, and identical in total fat and fiber as the test diet, for 28 days | Other: Nut-free diet<br> <br> * Other names: Isocaloric diet absent nuts and matched for total fat and fiber for 28 days.;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in biomarkers of oxidative stress compared with control diet |  | Baseline and 4 weeks | 
| Change in biomarkers of inflammation compared with control diet |  | Baseline and 4 weeks. | 
| Change in biomarkers of endothelial function compared with control diet |  | Baseline and 4 weeks. | 
| Change in biomarkers of antioxidant activity compared with control diet |  | Baseline and 4 weeks | 
| Change in biomarkers of insulin resistance compared with control diet |  | Baseline and 4 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in blood pressure compared with control diet |  | Baseline and 4 weeks | 
| Change in plasma lipid profile compared with control diet |  | Baseline and 4 weeks. |