A Low Glycemic Index Diet for Prevention of Glucose Intolerance During Bed Rest

Recovery from surgery, injury or illness might require periods of bed rest in-hospital or at home. Bed rest may be needed for recovery but also has negative consequences. Prolonged bed rest reduces the ability of muscle to take up sugar from the blood, and increases blood levels of sugar and fat which may actually delay recovery. Bone starts breaking down when there is very little skeletal stimulation or 'stress' that typically occurs with walking. Bed rest stiffens arteries which may increase blood pressure. Different diets may influence the extent of harmful effects to muscle, bone and arteries during bed rest. This study compares a diet with increased plant sources (i.e. lentils, chickpeas, beans and peas) to a typical hospital diet (mostly animal sources and foods high in refined sugar) on blood, arteries, muscle and bone during bed rest. The investigators will test six healthy adults before, during and after two periods of 4-day bed rest, one when they eat a typical hospital diet, one with a diet containing more plant sources. The investigators will learn more about the effects of diet during bed rest and be able to make recommendations about diets to help ensure healthy recovery for individuals requiring bed rest.

Study Overview

• Status: Completed
• Conditions: Glucose Intolerance
• Intervention / Treatment: Dietary supplement: Low glycemic index, pulse-based diet; Dietary supplement: Moderate glycemic index hospital diet

Detailed Description

Many medical conditions and interventions require periods of bed rest in order to maximize recovery and restore optimal physical function. Unfortunately, muscle becomes glucose intolerant, bone starts to break down, and arteries become stiffer during sustained periods of chronic inactivity, such as bed rest. Elevation of blood glucose during hospital stays results in increased morbidity, mortality, length of stay and costs. Components of the typical Western diet (refined carbohydrates and protein from animal sources common in hospital foods) induce glucose intolerance, bone catabolism, and arterial stiffening; plant-based proteins may not have the same negative impact. Pulses (i.e. low fat legumes: lentils, chickpeas, beans, peas) contain carbohydrate with a low glycemic index, and do not substantially increase blood glucose levels. At the same time, they are high in protein, but do not contain the same sulphur-containing amino acid profile as animal proteins that induce bone resorption. Pulses are, therefore, a potential 'super food' to mitigate many of the negative impacts associated with required bed rest following medical illness.

The study purpose is to determine the effects of a pulse-based diet compared to a Western diet of typical hospital foods on glucose tolerance, bone catabolism, and arterial stiffening during bed rest. The investigators hypothesize that a pulse-based diet will be superior to a typical Western diet for preventing glucose intolerance, bone catabolism, and arterial stiffening during sustained bed rest.

Six healthy adults will take part in a cross-over study where they will be randomized to four days of bed rest while on a pulse-based or Western diet, have a one month wash-out and then cross-over before another four days of bed rest with the other diet. Immediately before and after bed rest (i.e. the first morning after the last night of bed rest), oral glucose tolerance tests will be conducted to assess glucose tolerance and insulin sensitivity (i.e. markers used to assess diabetes risk). At the same time points, fasting blood samples will be collected for lipid assessments. Urine will be collected for assessment of bone catabolism (via measures of N-telopeptides: a by-product of collagen from bone which appears in the urine when bone is breaking down). Blood pressure will be evaluated every two hours during bed rest days from 9am to 9pm. Arterial stiffness (measured by the gold-standard technique of pulse wave velocity using applanation tonometry) and beat-by-beat blood pressure will be used to assess blood vessel function before and after four days of bed rest.

This study will inform improved hospital diets and nutritional habits of patients to prevent or offset negative health implications during periods of bed rest that may be required either in-hospital, long-term care or at home as part of standard medical care.

• Study Type: Interventional
• Enrollment (Actual): 6
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • Saskatchewan (SK)
    • Saskatoon, Saskatchewan (SK), Canada, S7N5B2
      • College of Kinesiology, University of Saskatchewan

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Healthy

Exclusion Criteria:

• Diabetic
• Vegetarian
• Food allergies

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: Low glycemic index diet; Low glycemic index pulse-based diet (i.e. beans, peas, lentils, chickpeas)	Dietary supplement: Low glycemic index, pulse-based diet; Diet that includes pulses (i.e. meals that contain chickpeas, lentils, beans, or peas)
ACTIVE_COMPARATOR: Regular hospital diet; Moderate glycemic index diet based on hospital menus	Dietary supplement: Moderate glycemic index hospital diet; Diet that is derived from a regular hospital menu for patients

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Glucose area under the curve	glucose area under the curve from 2-hour oral glucose tolerance test	Change from baseline to 4 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Insulin area under the curve	Insulin area under the curve from 2-hour oral glucose tolerance test	Change from baseline to 4 days
Fasting glucose	Fasting glucose from serum	Change from baseline to 4 days
Fasting insulin	Fasting Insulin from serum	Change from baseline to 4 days
Fasting cholesterol	Fasting cholesterol from serum	Change from baseline to 4 days
Fasting LDL-cholesterol	Fasting LDL-cholesterol from serum	Change from baseline to 4 days
Fasting triglycerides	Fasting triglycerides from serum	Change from baseline to 4 days
Fasting HDL-cholesterol	Fasting HDL-cholesterol from serum	Change from baseline to 4 days
Bone resorption	Urinary n-telopeptides	Change from baseline to 4 days
Lean tissue mass	Lean tissue mass from dual energy X-ray absorptiometry scans	Change from baseline to 4 days
Fat mass	Fat mass from dual energy X-ray absorptiometry scans	Change from baseline to 4 days
Systolic Blood pressure	Beat-by-beat blood pressure measurement	Change from baseline to 1, 2, 3, and 4 days
Arterial stiffness	Arterial stiffness assessed by tonometry	Change from baseline to 1, 2, 3, and 4 days
Diastolic blood pressure	Beat-by-beat blood pressure measurement	Change from baseline to 1, 2, 3, and 4 days

Collaborators and Investigators

• Sponsor: University of Saskatchewan
• Collaborators: Royal University Hospital Foundation

Study record dates

Study Major Dates

• Study Start (ACTUAL): July 15, 2018
• Primary Completion (ACTUAL): October 30, 2018
• Study Completion (ACTUAL): December 1, 2018

Study Registration Dates

• First Submitted: June 27, 2018
• First Submitted That Met QC Criteria: July 12, 2018
• First Posted (ACTUAL): July 23, 2018

Study Record Updates

• Last Update Posted (ACTUAL): December 12, 2018
• Last Update Submitted That Met QC Criteria: December 10, 2018
• Last Verified: December 1, 2018

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Glucose Metabolism Disorders; Metabolic Diseases; Hyperglycemia; Glucose Intolerance
• Other Study ID Numbers: 17-176

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