Avocado and Postprandial Responses

NCT06818032 | Recruiting

• 1 other identifier: STUDY00003379
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of this study is to see how adding avocado to a breakfast meal affects blood sugar control and signals of hunger and fullness after eating. The investigators will test the effects of 3 breakfast meals on blood sugar control and signals of hunger and fullness after eating:

1. 1.Whole-wheat bread and strawberry jam
2. 2.Whole-wheat bread, strawberry jam, and avocado
3. 3.Whole-wheat bread and strawberry jam (meal enriched with fat and fiber to mimic that of an avocado)

Conditions

Healthy; Healthy Volunteer; Healthy Volunteers; Healthy Adult; Healthy Male and Female Subjects; Healthy Subjects; Healthy Volunteers Only; Healthy Non-smokers

Keywords

Persea Americana; blood glucose; blood insulin; adiponectin; leptin; GLP-1; appetite; satiety; glucose tolerance; GIP; ghrelin; Peptide YY (PYY); glucose metabolism; dietary fats; meal challenge; meal tolerance test; dietary fiber; glycemia

Outcome Measures

Primary Outcomes (1)

• Diet-induced changes in postprandial glucose tolerance

  Blood glucose and insulin concentrations will be measured.

  60-minute time point, 120-minute time point, incremental area under the curve from fasting to 180-minute time point

Secondary Outcomes (1)

• Diet-induced changes in postprandial satiety hormones

  60-minute time point, 120-minute time point, incremental area under the curve from fasting to 180-minute time point

Study Arms (3)

Negative control breakfast

OTHER

Participants will receive a breakfast with bread and jam, no avocado.

Other: Negative control

Avocado addition breakfast

EXPERIMENTAL

Participants will receive a breakfast with bread, jam, and avocado.

Other: Avocado

Fat and fiber control breakfast

ACTIVE COMPARATOR

Participants will receive a breakfast with bread and jam, no avocado. The breakfast meal will be enriched with fat and fiber to mimic that of an avocado.

Other: Fat and fiber addition

Interventions

Negative control OTHER

Participants will be given a breakfast meal with 76 grams of bread and 60 grams of jam per 2000 daily calories.

Negative control breakfast

Avocado OTHER

Participants will be given a bread and jam breakfast (76 grams of bread and 60 grams of jam per 2000 daily calories) supplemented with 84 grams of avocado per 2000 daily calories.

Avocado addition breakfast

Fat and fiber addition OTHER

Participants will be given a bread and jam breakfast (76 grams of bread and 60 grams of jam per 2000 daily calories) supplemented with 13 grams of fat (mix of high-oleic safflower oil, safflower oil, palm oil, and macadamia nut oil) and 5.5 grams of fiber (mix of cellulose and pectin) per 2000 daily calories.

Fat and fiber control breakfast

Eligibility Criteria

• Age: 21 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Biological sex males or females
• Age 21 to 65 years
• BMI between 18.5 and 34.9 kg/m2

You may not qualify if:

• Actively pregnant or lactating women
• Diagnosis of prediabetes or diabetes (fasting glucose \>100 mg/dL)
• Current diagnosis of uncontrolled hypertension (systolic BP: \>160 mmHg, diastolic BP: \>95 mmHg), may receive treatment for hypertension as long as on a stable regimen for the previous one month
• Current diagnosis of uncontrolled hyperlipidemia (fasting total blood cholesterol \>200 mg/dL, fasting triglycerides \>200 mg/dL), may receive treatment for hyperlipidemia as long as on a stable regimen for the previous one month
• Presence of kidney disease, liver disease, hyperthyroidism, untreated or unstable hypothyroidism, certain cancers, gastrointestinal disease, pancreatic disease, other chronic metabolic diseases or malabsorption syndromes, HIV, or inflammatory conditions (such as arthritis, asthma, Crohn's disease, inflammatory bowel disease, gout, Lupus)
• History of bariatric or certain other surgeries related to weight control
• Any medication used to lower blood glucose/antidiabetic medications \[including, but not limited to metformin, sulfonylureas, glucagon-like peptide-1 (GLP-1) analogues, sodium-glucose cotransporter-2 (SGL2) inhibitors, thiazolidinediones, dipeptidyl peptidase (DPP)-IV inhibitors\] as well as medications affecting weight, appetite/hunger or gut motility.
• Smoking or use of other tobacco products (during 6 months prior to the start of the study)
• Antibiotic use during the intervention or for 3 weeks prior to any treatment period
• History of eating disorders or other significant food preferences that would interfere with the diet intervention (e.g., vegan lifestyle, very low-fat diets, high-protein diets)
• Allergies or adverse reactions to study foods (e.g., gluten intolerance), or food aversions that would interfere with diet adherence
• Body weight loss of \>10% within the last 6 months prior to study start
• Unable or unwilling to give informed consent or communicate with study staff
• 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
• Undergoing hormonal therapy of any kind, with the exception of a stable regime for the prior 6 months to study start.

Sponsors & Collaborators

• University of Vermont Medical Center: lead
• Avocado Nutrition Center: collaborator

Study Sites (1)

Clinical Research Center, University of Vermont Medical Center

Burlington, Vermont, 05405, United States

RECRUITING

Related Publications (21)

• https://hassavocadoboard.com/happenings/2023-year-in-review/.

  BACKGROUND

• Zhu L, Huang Y, Edirisinghe I, Park E, Burton-Freeman B. Using the Avocado to Test the Satiety Effects of a Fat-Fiber Combination in Place of Carbohydrate Energy in a Breakfast Meal in Overweight and Obese Men and Women: A Randomized Clinical Trial. Nutrients. 2019 Apr 26;11(5):952. doi: 10.3390/nu11050952.

  PMID: 31035472 BACKGROUND

• Wright J. Effect of high-carbohydrate versus high-monounsaturated fatty acid diet on metabolic control in diabetes and hyperglycemic patients. Clin Nutr. 1998 Sep;17 Suppl 2:35-45. doi: 10.1016/s0261-5614(98)80016-2. No abstract available.

  PMID: 10205358 BACKGROUND

• U.S. Department of Agriculture and U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2020-2025. 9th Edition.

  BACKGROUND

• Sanchez D, Miguel M, Aleixandre A. Dietary fiber, gut peptides, and adipocytokines. J Med Food. 2012 Mar;15(3):223-30. doi: 10.1089/jmf.2011.0072. Epub 2011 Dec 19.

  PMID: 22181071 BACKGROUND

• Rocca AS, LaGreca J, Kalitsky J, Brubaker PL. Monounsaturated fatty acid diets improve glycemic tolerance through increased secretion of glucagon-like peptide-1. Endocrinology. 2001 Mar;142(3):1148-55. doi: 10.1210/endo.142.3.8034.

  PMID: 11181530 BACKGROUND

• Qian F, Korat AA, Malik V, Hu FB. Metabolic Effects of Monounsaturated Fatty Acid-Enriched Diets Compared With Carbohydrate or Polyunsaturated Fatty Acid-Enriched Diets in Patients With Type 2 Diabetes: A Systematic Review and Meta-analysis of Randomized Controlled Trials. Diabetes Care. 2016 Aug;39(8):1448-57. doi: 10.2337/dc16-0513.

  PMID: 27457635 BACKGROUND

• Pedreschi R, Uarrota V, Fuentealba C, Alvaro JE, Olmedo P, Defilippi BG, Meneses C, Campos-Vargas R. Primary Metabolism in Avocado Fruit. Front Plant Sci. 2019 Jun 26;10:795. doi: 10.3389/fpls.2019.00795. eCollection 2019.

  PMID: 31293606 BACKGROUND

• Park E, Edirisinghe I, Burton-Freeman B. Avocado Fruit on Postprandial Markers of Cardio-Metabolic Risk: A Randomized Controlled Dose Response Trial in Overweight and Obese Men and Women. Nutrients. 2018 Sep 12;10(9):1287. doi: 10.3390/nu10091287.

  PMID: 30213052 BACKGROUND

• Nansel TR, Lipsky LM, Liu A. Greater diet quality is associated with more optimal glycemic control in a longitudinal study of youth with type 1 diabetes. Am J Clin Nutr. 2016 Jul;104(1):81-7. doi: 10.3945/ajcn.115.126136. Epub 2016 May 18.

  PMID: 27194309 BACKGROUND

• Muller M, Canfora EE, Blaak EE. Gastrointestinal Transit Time, Glucose Homeostasis and Metabolic Health: Modulation by Dietary Fibers. Nutrients. 2018 Feb 28;10(3):275. doi: 10.3390/nu10030275.

  PMID: 29495569 BACKGROUND

• Levitan EB, Song Y, Ford ES, Liu S. Is nondiabetic hyperglycemia a risk factor for cardiovascular disease? A meta-analysis of prospective studies. Arch Intern Med. 2004 Oct 25;164(19):2147-55. doi: 10.1001/archinte.164.19.2147.

  PMID: 15505129 BACKGROUND

• Livesey G, Taylor R, Livesey HF, Buyken AE, Jenkins DJA, Augustin LSA, Sievenpiper JL, Barclay AW, Liu S, Wolever TMS, Willett WC, Brighenti F, Salas-Salvado J, Bjorck I, Rizkalla SW, Riccardi G, Vecchia C, Ceriello A, Trichopoulou A, Poli A, Astrup A, Kendall CWC, Ha MA, Baer-Sinnott S, Brand-Miller JC. Dietary Glycemic Index and Load and the Risk of Type 2 Diabetes: Assessment of Causal Relations. Nutrients. 2019 Jun 25;11(6):1436. doi: 10.3390/nu11061436.

  PMID: 31242690 BACKGROUND

• Ingram DK, Roth GS. Glycolytic inhibition: an effective strategy for developing calorie restriction mimetics. Geroscience. 2021 Jun;43(3):1159-1169. doi: 10.1007/s11357-020-00298-7. Epub 2020 Nov 12.

  PMID: 33184758 BACKGROUND

• Giuntini EB, Sarda FAH, de Menezes EW. The Effects of Soluble Dietary Fibers on Glycemic Response: An Overview and Futures Perspectives. Foods. 2022 Dec 6;11(23):3934. doi: 10.3390/foods11233934.

  PMID: 36496742 BACKGROUND

• Gillingham LG, Harris-Janz S, Jones PJ. Dietary monounsaturated fatty acids are protective against metabolic syndrome and cardiovascular disease risk factors. Lipids. 2011 Mar;46(3):209-28. doi: 10.1007/s11745-010-3524-y. Epub 2011 Feb 10.

  PMID: 21308420 BACKGROUND

• Ford NA, Spagnuolo P, Kraft J, Bauer E. Nutritional Composition of Hass Avocado Pulp. Foods. 2023 Jun 28;12(13):2516. doi: 10.3390/foods12132516.

  PMID: 37444254 BACKGROUND

• FoodData Central. Avocados, raw, California. Available online: https://fdc.nal.usda.gov/fdc-app.html#/food-details/171706/nutrients

  BACKGROUND

• FruiTrop. Close-up avocado. In FruiTrop Magazine; Loeillet, D., Imbert, E., Eds.; Cirad: Montpellier, France, 2015; pp. 1-96.

  BACKGROUND

• Akhlaghi M. The role of dietary fibers in regulating appetite, an overview of mechanisms and weight consequences. Crit Rev Food Sci Nutr. 2024;64(10):3139-3150. doi: 10.1080/10408398.2022.2130160. Epub 2022 Oct 4.

  PMID: 36193993 BACKGROUND

• Abdul-Ghani MA, Williams K, DeFronzo R, Stern M. Risk of progression to type 2 diabetes based on relationship between postload plasma glucose and fasting plasma glucose. Diabetes Care. 2006 Jul;29(7):1613-8. doi: 10.2337/dc05-1711.

  PMID: 16801587 BACKGROUND

MeSH Terms

Interventions

CD36 Antigens

Intervention Hierarchy (Ancestors)

Platelet Membrane Glycoproteins; Membrane Glycoproteins; Glycoproteins; Glycoconjugates; Carbohydrates; Fatty Acid Transport Proteins; Membrane Transport Proteins; Carrier Proteins; Proteins; Amino Acids, Peptides, and Proteins; Membrane Proteins; Receptors, Cell Surface; Receptors, Immunologic; Scavenger Receptors, Class B; Receptors, Scavenger; Receptors, LDL; Receptors, Lipoprotein

Study Officials

• Jana Kraft, Ph.D.

  University of Vermont

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Clinical Research Project Manager

CONTACT

802-656-8827; foodstudy@uvm.edu

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Study Record Dates

• First Submitted: February 4, 2025
• First Posted: February 10, 2025
• Study Start: March 1, 2025
• Primary Completion: February 1, 2026
• Study Completion (Estimated): June 1, 2026
• Last Updated: March 28, 2025

Record last verified: 2025-03

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)