Pinto Beans and Glycemic Control in Adults With Type 2 Diabetes

Impact of Pinto Beans as Part of a Normal Diet on Glycemic Control in Adults With Type 2 Diabetes: a Randomized Trial

This study examines the impact of daily consumption of ½ c pinto beans, compared to a control (½ c green beans), on fasting glucose, postprandial glucose and HbA1c concentrations in adults with type 2 diabetes mellitus (T2DM).

Study Overview

• Status: Completed
• Conditions: Type 2 Diabetes
• Intervention / Treatment: Other: Pinto Beans; Other: Green Beans - control

Detailed Description

This study utilized a randomized, pretest-posttest, crossover (within-group) design, that includes two treatment periods [control period (½ c. green beans each day) and pinto beans (½ c each day)], each 12-weeks in duration with a 4- week wash-out period to determine the impact on fasting glucose, postprandial glucose and HbA1c concentrations. After a baseline wash-in period, 16 participants are randomly assigned to 2 treatment periods [control period and pinto beans], each 12-weeks in duration. On 28 randomized days during the wash-in period and interventions, participants keep diet records and measure a postprandial capillary glucose concentration using a glucometer 1 hour after the meal during which the pinto beans or control are consumed. Before and after each 12-week intervention, participants provide a fasted venous blood sample for glucose and HbA1c analyses.

• Study Type: Interventional
• Enrollment (Actual): 13
• Phase: Not Applicable

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years to 75 years (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• diagnosis of T2DM by a physician;
• currently attempting control of T2DM by diet or metformin;
• fasting glucose ≥ 90 mg/dL (confirmed by fasting blood draw or potential participant provided lab analysis conducted within last 30 days) and/or hemoglobin A1C ≥ 6.5% (confirmed by blood draw or potential participant provided lab analysis conducted within last 30 days);
• body mass index (BMI) of 22-40 kg/m2;
• no unresolved health conditions and no diagnosis of gastrointestinal disease;
• limited history of legume intake;
• willingness to follow study protocol, scheduling, and ability to come to the testing location;
• no recent weight gain or loss (>10% over 6 months);
• no use of medications and/or dietary supplements other than metformin that affected glucose;
• women could not be pregnant or breastfeeding;
• habitual alcohol consumption had to be less than 2 drinks per day (specifically ≤ 720 ml of beer, 240 ml of wine, or 90 ml of hard liquor).

Exclusion Criteria:

• Non compliance with above inclusion criteria.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: BASIC_SCIENCE
• Allocation: RANDOMIZED
• Interventional Model: CROSSOVER
• Masking: NONE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: Pinto beans; 1/2 cup pinto beans eaten daily by free-living individuals for 12 consecutive weeks.	Other: Pinto Beans; The intervention was 1/2 cup of pinto beans each day.; Other Names: Pinto Beans - intervention
ACTIVE_COMPARATOR: Green beans; 1/2 cup green beans eaten daily by free-living individuals for 12 consecutive weeks.	Other: Green Beans - control; The control was 1/2 cup of green beans each day.; Other Names: Control

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Glucose	Change in fasting blood glucose levels	12 weeks pre and post

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Postprandial glucose	1 time per week from week 1 of each intervention to week 12 of each intervention	1 time per week from week 1 of each intervention to week 12 of each intervention
Change in Hemoglobin A1c	Change in Blood hemoglobin A1c	12 weeks pre and post

Collaborators and Investigators

• Sponsor: University of Colorado, Colorado Springs
• Collaborators: Iowa State University

Study record dates

Study Major Dates

• Study Start (ACTUAL): March 1, 2009
• Primary Completion (ACTUAL): December 31, 2010
• Study Completion (ACTUAL): December 31, 2010

Study Registration Dates

• First Submitted: June 24, 2019
• First Submitted That Met QC Criteria: June 28, 2019
• First Posted (ACTUAL): July 1, 2019

Study Record Updates

• Last Update Posted (ACTUAL): July 1, 2019
• Last Update Submitted That Met QC Criteria: June 28, 2019
• Last Verified: June 1, 2019

More Information

Terms related to this study

• Keywords: legumes; glycemic response; pulses; Phaseolus vulgaris L.
• Additional Relevant MeSH Terms: Glucose Metabolism Disorders; Metabolic Diseases; Endocrine System Diseases; Diabetes Mellitus; Diabetes Mellitus, Type 2
• Other Study ID Numbers: UCCS09-028

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No