Habitual Diet and Avocado Trial

Diabetes Clinical Trial

— HAT  

Official title:

Habitual Diet and Avocado Trial

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT03528031
• Other study ID #: IRB00047011
• Status: Completed
• Phase: N/A
• Start date: June 19, 2018
• Est. completion date: October 30, 2020

Study information

• Verified date: June 2021
• Source: Wake Forest University Health Sciences
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The Habitual Diet and Avocado Trial will evaluate the effects of providing one avocado per day for recommended consumption over a 6 month period in a cohort of approximately 1000 free-living participants with increased waist circumference in comparison with a control group that will maintain their habitual diets. Participants will be recruited and screened at 4 clinics in 4 locations: Pennsylvania State University; Loma Linda University; UCLA, and Tufts University (250 per site).

Description:

Preliminary evidence suggests that consumption of avocados can modulate body weight, food intake and markers of metabolic syndrome and may reduce visceral adiposity. Visceral adipose tissue is positively correlated with risk of cardiometabolic syndrome that predisposes to cardiovascular disease and diabetes. The Habitual Diet and Avocado Trial (HAT) aims to investigate an impactful outcome (visceral fat reduction) in a relevant population (Americans with an increased weight circumference) with a reasonable lifestyle modification (consumption of 1 avocado per day). HAT will evaluate the effect of providing one avocado per day for consumption over a 6 month period on established health parameters, including visceral adiposity, hepatic lipid content, markers of metabolic syndrome and high sensitivity C-reactive protein (hsCRP) when compared to a habitual diet. Blood specimens will be drawn and analyzed for fasting total cholesterol, triglyceride, HDL-C, glucose, insulin, hsCRP and RBC fatty acid profiles. Two non-contrast MRIs will be performed (at screening to assess eligibility and final participant visit 8 for randomized participants) to assess the volume of visceral adipose tissue and hepatic fat fraction. Four 24-hour dietary recalls will be conducted for study participants to capture dietary intake data. Questionnaires include the following: health and demographic including eating habits and physical activity; diet, food and avocado satisfaction (intervention group only); quality of life; and quality of sleep.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 1008
• Est. completion date: October 30, 2020
• Est. primary completion date: October 16, 2020
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 25 Years and older

Eligibility

Inclusion Criteria:

• Increased waist circumference defined as =35 inches for women, =40 inches for men
• At least 25 years old at screening
• Not currently eating more than 2 avocados per month (habitual intake in U.S.)

Exclusion Criteria:

• Does not eat avocados
• Sensitive / allergic to avocados
• Allergies to latex or oral allergy syndrome
• Not willing or unable to undergo MRI scans
• Unstable medical condition such as on dialysis for renal disease, cardiac, gastrointestinal, or hepatic disease, cancer (non-melanoma skin cancer >5 years ago acceptable, any cancer site >10yrs without recurrence).
• Pregnant, lactating, intention of pregnancy
• Lost or gained 10 lbs of body weight in last year
• Following restricted or weight loss dietary patterns
• Unstable anti-anxiety / anti-depressive / anti-psychotic medication use defined as dose change within last 6 months
• Oral steroid use within the last 6 months longer than 7 days
• Elevated alcohol intake (7+ drinks/week females; 14+ drinks/week males)
• Participation in another clinical intervention trial within 30 days of baseline
• PI judgment

Related Conditions & MeSH terms

• Cardiovascular Diseases
• Cardiovascular Risk Factor
• Diabetes
• Diet Habit
• Dietary Modification
• HDL Cholesterol, Low Serum
• High Blood Sugar
• High Cholesterol
• High Density Lipoprotein Deficiency
• Hypercholesterolemia
• Hyperglycemia
• Hypoalphalipoproteinemias
• Hypolipoproteinemias
• Intra-abdominal Fat
• Liver Fat
• Low-density-lipoprotein-type
• Metabolic Syndrome
• Triglycerides High

Intervention

Other:
• Intervention Daily Avocado
Participants follow their usual diet and lifestyle but also are provided with 1 avocado to consume per day for 6 months.

Locations

Country	Name	City	State
United States	Tufts University	Boston	Massachusetts
United States	Loma Linda University	Loma Linda	California
United States	University of California Los Angles (UCLA)	Los Angeles	California
United States	Pennysylvania State University	University Park	Pennsylvania

Sponsors (1)

Lead Sponsor	Collaborator
Wake Forest University Health Sciences

Country where clinical trial is conducted

United States, 

References & Publications (11)

Berryman CE, West SG, Fleming JA, Bordi PL, Kris-Etherton PM. Effects of daily almond consumption on cardiometabolic risk and abdominal adiposity in healthy adults with elevated LDL-cholesterol: a randomized controlled trial. J Am Heart Assoc. 2015 Jan 5; — View Citation

Bertoli S, Leone A, Vignati L, Bedogni G, Martinez-Gonzalez MA, Bes-Rastrollo M, Spadafranca A, Vanzulli A, Battezzati A. Adherence to the Mediterranean diet is inversely associated with visceral abdominal tissue in Caucasian subjects. Clin Nutr. 2015 Dec — View Citation

Cespedes Feliciano EM, Tinker L, Manson JE, Allison M, Rohan T, Zaslavsky O, Waring ME, Asao K, Garcia L, Rosal M, Neuhouser ML. Change in Dietary Patterns and Change in Waist Circumference and DXA Trunk Fat Among Postmenopausal Women. Obesity (Silver Spr — View Citation

Dhillon J, Tan SY, Mattes RD. Almond Consumption during Energy Restriction Lowers Truncal Fat and Blood Pressure in Compliant Overweight or Obese Adults. J Nutr. 2016 Dec;146(12):2513-2519. doi: 10.3945/jn.116.238444. Epub 2016 Nov 2. — View Citation

Estruch R, Martinez-Gonzalez MA, Corella D, Salas-Salvado J, Ruiz-Gutierrez V, Covas MI, Fiol M, Gomez-Gracia E, Lopez-Sabater MC, Vinyoles E, Aros F, Conde M, Lahoz C, Lapetra J, Saez G, Ros E; PREDIMED Study Investigators. Effects of a Mediterranean-sty — View Citation

Gower BA, Goss AM. A lower-carbohydrate, higher-fat diet reduces abdominal and intermuscular fat and increases insulin sensitivity in adults at risk of type 2 diabetes. J Nutr. 2015 Jan;145(1):177S-83S. doi: 10.3945/jn.114.195065. Epub 2014 Dec 3. — View Citation

National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III). Third Report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection — View Citation

O'Neil, et al. Avocado consumption by adults is associated with better nutrient intake, diet quality and some measures of adiposity: NHANES Survey, 2001-2012. Int Med Rev In press.

Paniagua JA, Gallego de la Sacristana A, Romero I, Vidal-Puig A, Latre JM, Sanchez E, Perez-Martinez P, Lopez-Miranda J, Perez-Jimenez F. Monounsaturated fat-rich diet prevents central body fat distribution and decreases postprandial adiponectin expressio — View Citation

Ross R, Rissanen J, Pedwell H, Clifford J, Shragge P. Influence of diet and exercise on skeletal muscle and visceral adipose tissue in men. J Appl Physiol (1985). 1996 Dec;81(6):2445-55. doi: 10.1152/jappl.1996.81.6.2445. — View Citation

Wien M, Haddad E, Oda K, Sabate J. A randomized 3x3 crossover study to evaluate the effect of Hass avocado intake on post-ingestive satiety, glucose and insulin levels, and subsequent energy intake in overweight adults. Nutr J. 2013 Nov 27;12:155. doi: 10 — View Citation

* Note: There are 11 references in all — Click here to view all references

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Visceral adiposity	Non-contrast MRI scans will be performed to assess the volume of visceral adipose tissue. The outcome will be pre-post difference, compare the estimated mean change from baseline to follow-up in the 2 randomized groups with all tests of group differences performed according to the intent to treat.	Visit 1 (Screening, -2 to 0 weeks) and Visit 8 (26 weeks)
Secondary	Hepatic lipid content	Non-contrast MRI scans will be performed to assess hepatic lipid content/hepatic fat fraction.	Visit 1 (Screening, -2 to 0 weeks and Visit 8 (26 weeks)
Secondary	Metabolic syndrome markers (serum triglycerides, serum cholesterol, fasting serum glucose, fasting insulin)	Phlebotomy is performed after a minimum 8 hour fast. Specimens will be separated and aliquoted, and shipped for analysis to Tufts University site for: fasting total cholesterol, triglyceride, high density lipo-protein cholesterol (HDL-C), glucose and insulin. LDL will be calculated using the Friedewald equation unless fasting triglyceride levels are > 400 mg/dL in which case they will be measured using a direct LDL assay. There will be a comparison of the estimated mean change from baseline to follow-up with all tests of group differences performed according to intent to treat.	Visit 2 (Baseline visit 0 weeks), Visit 5 (12 weeks), Visit 8 (26 weeks)
Secondary	High-sensitivity C-reactive protein (hs-CRP)	C-reactive protein (CRP) is a protein that the liver makes when there is inflammation in the body. Also called a marker of inflammation and can be measured with the hs-CRP test. Inflamed arteries puts individuals at greater risk of heart disease, heart attack, stroke and peripheral arterial disease. A fasting sample will be obtained, shipped to and analyzed at Tufts University for hsCRP.	Visit 2 (baseline/randomization, Week 0), Visit 5 (12 weeks), Visit 8 (26 weeks)
Secondary	Red blood cell (RBC) monounsaturated fat/polyunsaturated fat (MUFA/PUFA) ratio	Fasting RBC specimens shipped to Tufts University for analysis of RBC fatty acid profiles. The Fatty Acid Profile measures major fatty acids found in red blood cells.	Visit 2 (Baseline/Randomization Visit, 0 weeks), Visit 5 (12 weeks), Visit 8 (26 weeks)
Secondary	Blood pressure	Seated blood pressure will be measured at each visit (except the screening visit) utilizing automated devices as per a standardized protocol across all sites. Three measurements will be taken after a 5 minute rest period, 1 minute apart. The last two readings are averaged for analysis.	Visit 2 (baseline/randomization 0 weeks) Visit 3 (4 weeks), Visit 4 (8 weeks), Visit 5 (12 weeks), Visit 6 (16 weeks), Visit 7 (10 weeks), Visit 8 (26 weeks)
Secondary	Weight	Participants will be weighed at all in-study visits using high quality digital scales commonly used in clinical practice and that are in good working order. Participants will be weighed in light street clothes without shoes. The same scale is used throughout the trial.	Visit 2 (baseline/randomization), Visit 5 (12 weeks) and Visit 8 (26 weeks-final)
Secondary	Waist circumference	A measuring tape specifically designed for waist circumference (recommended brands include Gulick or Seca) will be used according to a standardized procedure outlined in the trial Manual of Procedures. Waist circumference will be used during screening to assess eligibility. Measurements will be taken against the skin at the approximate midpoint between the lower margin of the last palpable rib and the top of the iliac crest. Two measurements are obtained at each visit and averaged.	Visit 1 (screening -2 to 0 weeks), Visit 2 (baseline/randomization 0 weeks), Visit 5 (12 weeks), Visit 8 (26 weeks)
Secondary	Diet, Food and Avocado Satisfaction	Questions regarding participant satisfaction with the diet and food intervention will be assessed by completing the Diet, Food and Avocado Satisfaction Questionnaire. The questionnaire will only be completed by participants randomized to consume one avocado a day. The questionnaire is completed within 24 hours of a clinic visit and can be self- or staff administered. It consists of 14 questions about eating and preparing avocados each having a 100 point Likert scale with responses of "Not at all" and "Extremely".	Visit 2 (baseline/randomization, 0 weeks), Visit 5 (12 weeks), Visit 8 (26 weeks)
Secondary	Quality of life RAND 36-Item Short Form Survey Instrument (SF-36)	All participants will complete the RAND (research and development) 36-Item Health Survey to assess 8 health concepts: physical functioning, bodily pain, role limitations due to personal or emotional problems, emotional well-being, social functioning, energy/fatigue and general health perceptions.All items are scored so that a high score defines more favorable health state. Each item is scored on a 0 to 100 range so that the lowest and highest possible scores are 0 and 100. Items in the same scale are averaged together to create 8 scale scores. Items that are left blank are not taken into account when calculating scale scores.	Visit 2 (baseline), Visit 5 (12 weeks) and Visit 8 (26 weeks-final)
Secondary	Quality of Life RAND 20-Item Short Form Survey (SF-20)	The 20-item Short Form Health Survey (SF-20) was designed to reduce respondent burden while achieving minimum standards of precision for purposes of group comparisons involving multiple health dimensions. It includes 7 items to assess physical functioning, 2 items on role functioning, 1 social functioning survey item, 5 items to assess mental health, 4 items on current health perceptions and 1 item on pain. Participants in the control group will complete the RAND 20-Item Short Form Survey.	Visit 3 (4 weeks), Vist 4 (8 weeks) Visit 6 (16 weeks), Visit 7 (20 weeks)
Secondary	Sleep quality	All participants will complete the Pittsburgh Sleep Quality Index questionnaire (PSQI) which is a self-rated questionnaire that assesses sleep quality and disturbances over a 1-month time time interval. 19 individual items generate seven "component" scores: subjective sleep quality; sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, use of sleeping medication and daytime dysfunction. The sum of scores for the 7 components yield one global score.	Visit 2 (baseline), Visit 5 (12 weeks) and Visit 8 (26 weeks-final)
Secondary	24-hour diet recall	Four 24-hour dietary recalls will be conducted for each study participant during the course of the study. The goal for the 3 intra-study recalls is to capture intake data for 2 weekdays and 1 weekend day for each participant. The recalls are collected and analyzed using Nutrition Data System for Research (NDSR) software Vs 2017. The Loma Linda University site and Tufts University will be responsible for collecting 50% each of the 24 hour recalls across all study sites. They will follow a standardized manual of procedures for dietary data collection and dietary data management. Outcome data from NDSR will include daily estimated energy and nutrient intake, as well as food, food group and dietary supplement data.	Visit 1 (screening, -2 to 0 weeks), Visit 4 (8 weeks), visit 6 (16 weeks), Visit 8 (26 weeks)