Assessing the Value of Avocados on Glycemic Control in Type 2 Diabetes

Study Overview
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Brief Summary
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The objective of this study is to assess the effects of Hass Avocados on glycemic control. The investigators hypothesize that Hass Avocado consumption will reduce fasting blood sugar compared to an isocaloric amount of other fruit during controlled feeding.

Official Title
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The Effects of Hass Avocados on Glycemic Control in Persons With Type 2 Diabetes: A Randomized Controlled Crossover Trial

Conditions
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Diabetes Mellitus, Type 2, Insulin, Fructosamine, C-Reactive Protein, Glucose, Overweight and Obesity

Intervention / Treatment
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* Other: Avocado
* Other: Other Fruit(s)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Participant reported diagnosis of Type 2 diabetes HbA1c between 5.7%-11% (inclusive) and / or fasting blood glucose of ≥ 100 mg/dL BMI 27-50 kg/m2 (inclusive) Age range - 18 - 65 years (inclusive) On stable regimen of all medications (including diabetes) for at least 3 months (brief regimens of medications such as antibiotics, steroids, etc. are permitted) Willing to follow all requirements of study protocol including blood draws Under the care of a physician who will be responsible for managing the subject's diabetes Willing to give release to provide their treating MD with information about the trial Exclusion Criteria: Not willing or unable to consume study foods including avocados Participation in a weight control program within the past 3 months or weight loss of ≥ 5 kg in the previous 3 months Taking prescription or OTC weight loss medications within last 4 weeks History of a surgical procedure for weight loss in last 5 years (e.g. gastroplasty, gastric by-pass, gastrectomy or partial gastrectomy, adjustable banding, gastric sleeve) History of major surgery within three months of enrollment Type 1 diabetes, insulin dependent type 2 diabetes, thiazolidinediones (including rosiglitazone and pioglitazone) Renal insufficiency consisting of potassium over 5.5 (mmol/L) on a non-hemolyzed specimen, or a creatinine over 2.5 mg/dL Bilirubin over 3 (mg/dL) or an albumin less than 3 (g/dL) ALT > 3 (IU/L) times the upper limit of normal (normal range is 7-56) Evidence of more than 1 severe hypoglycemic event (episode requiring emergency medical services) in the past 12 months, unless the participant's treating physician provides written clearance for participation. Those on higher doses of diuretics (furosemide 40mg or higher or comparable) Unstable heart disease (an ongoing workup or treatment for a cardiac symptom such as unstable angina, coronary ischemia) Presence of implanted cardiac defibrillator Blood pressure ≥180/100 mm Hg. If a potential participant has a BP above the inclusion criteria it is acceptable to re-test this potential participant within one week of the original test. Thyroid disease for which the participant is untreated or has had treatment changed within the last 6 months. History of thyroid disease or current thyroid disease treated with a stable medication regimen for at least 6 months is acceptable Uncontrolled gastrointestinal disorders including chronic malabsorptive conditions, peptic ulcer disease, Crohn's disease, chronic diarrhea, or active gallbladder disease Current cancer or cancer treatment, or a history of cancer or cancer treatment within the last 3 years. Persons with successfully resected non-melanoma carcinoma of the skin may be enrolled. Dementia, psychiatric illness, or substance abuse that may interfere with adherence (e.g., illness that is currently unstable or resistant to first-line therapy; substance abuse in the past year) Women who are pregnant, lactating, trying to become pregnant or unwilling to use an effective means of birth control Currently consuming >14 alcoholic drinks (1 drink = 12 fl oz beer, 4 fl oz wine or 1.5 fl oz liquor) per week and unwilling to stop intake during study participation Participation in another clinical trial within 30 days prior to enrollment Any other condition or factor which in the opinion of the study physician or investigator makes it inadvisable for the candidate to participate in the trial

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 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: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: This study utilizes a randomized crossover design with each period/treatment being approximately 5 weeks. Participants will be randomized to either Hass Avocado or other fruit(s) consumption groups. The treatments will be isocaloric as will the Hass Avocado vs. the other fruit(s). All subjects will consume a diet provided by the metabolic research kitchen. The diet will be matched on energy (kcal).
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Avocado<br>Participants will consume 1 Hass avocado a day. | Other: Avocado<br>* The Hass Avocado group will consume 7 avocados a week (1 / day;  240 kcals/d).<br>* Other names: Hass Avocado;|
| Active Comparator: Other Fruit(s)<br>Participants in the other fruit arm will receive other fruits. | Other: Other Fruit(s)<br>* The other fruits group will consume fruit(s) matched to the avocado in energy and form (i.e., solid fruit).<br>* Other names: Raisins, Cantaloupe(s), Figs, Pineapple(s), Grapes, Bananas;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Fasting Blood Glucose | the primary outcomes are based on within subject concentration change scores | Week 5 - Week 0 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Fasting Insulin | within subject concentration change scores | Week 5 - Week 0 | 
| Fructosamine | within subject concentration change scores | Week 5 - Week 0 | 
| Glycated Albumin | within subject concentration change scores | Week 5 - Week 0 |