Clinical Trial Details
— Status: Not yet recruiting
Administrative data
| NCT number |
NCT04910828 |
| Other study ID # |
REB 20-114 |
| Secondary ID |
|
| Status |
Not yet recruiting |
| Phase |
N/A
|
| First received |
|
| Last updated |
|
| Start date |
June 1, 2021 |
| Est. completion date |
September 30, 2021 |
Study information
| Verified date |
May 2021 |
| Source |
University of Toronto |
| Contact |
David Jenkins, MD, PhD |
| Phone |
416-867-7475 |
| Email |
david.jenkins[@]utoronto.ca |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Interventional
|
Clinical Trial Summary
The aim of this study is to test high and low glycemic index foods in healthy adult
volunteers and determine the effects on post meal pulse and blood pressure. Foods will be
consumed before 8am after an overnight fast (10-12 hours) over a 10-15 minute period. Pulse
and BP (where equipment is available) measurements will be taken 6 times at 5 min intervals
before eating, and twice every 15 min thereafter for the following 2h. We will recruit
between 30 to 40 students and 10 to 20 older adults to assess the effect of age, in cohorts
of 10.
Description:
STUDY OBJECTIVE
The aim of this study is to test high and low glycemic index foods in healthy volunteers and
determine the effects on post meal pulse and blood pressure.
METHODS
Participants: 30 to 40 students and 10 to 20 older adults (>60 years) will be recruited.
Inclusion:
-Healthy adult volunteers
Exclusion:
-Serious health condition preventing participants from eating 50g of "available"
carbohydrates as a test breakfast. For example: 1) food intolerances or allergies to common
foods; 2) gastrointestinal conditions requiring medical treatment (Crohn's, ulcerative
colitis) and a special diet; 3) bariatric surgery.
Recruitment Study participants will be recruited from those who have contacted us and showed
interest in working with our group as well as colleagues who show interest in this project.
The study coordinator will obtain consent by telephone and confirm by email.
Study Design Fifty of the original 65 carbohydrate foods, as used in the 1981 AJCN (American
Journal Of Clinical Nutrition) glycemic index paper, that established the first comprehensive
values for the glycemic index of foods, will be fed to healthy volunteers as 50g carbohydrate
portions as was done for the original GI testing. Foods will be consumed before 8am after an
overnight fast (10-12 hours) over a 10-15 minute period. Pulse and BP (where equipment is
available) measurements will be taken 6 times at 5 min intervals before eating, and twice
every 15 min thereafter for the following 2h. Participants will be asked to test at least 10
(or more as they wish) foods on separate days. The minimum duration for their participation
will therefore be 10 days but not necessarily consecutively.
Sample Size We will recruit between 30 to 40 students and 10 to 20 older adults to assess the
effect of age, in cohorts of 10, and to have the flexibility for volunteers to do less foods
but still have a wide range of foods on which to obtain a tachycardia or hypotension index.
Procedures Prior to starting the study, they will be asked to complete a medical
questionnaire sent to them by email and return it to the study coordinator for review.
Participants will either come to the Risk Factor Modification Centre at St. Michael's
Hospital if pandemic restrictions allow, or will carry out the testing by themselves at home.
Tests will be carried out after an overnight fast. Participants will sit quietly for 15
minutes and then repeat pulse (and BP with the Omron or other monitor if available)
measurements 6 x at 5 min intervals or until measurements are consistent for 3 consecutive
readings.
The test meal breakfast will then be eaten over 10-15 minutes, with 2 further pulse
measurements taken at 15 minute intervals for the following 2h after the start of breakfast.
Throughout, participants will be asked to remain seated and emotionally uninvolved with their
environment. Pulse can be counted for 30 seconds to ensure concentration (and x by 2 for the
minute value). Written work, answering emails etc. can be undertaken providing the timing of
pulse measurements does not induce stress. The first 2h are crucial in this respect.
Study Intervention/Breakfasts Participants will be given a list of 10 foods (including white
bread to be used as the standard), and their weights and method of preparation. They will
acquire these common foods themselves. If they have no scales available, they will portion
the foods using common measures and the values with which they will be provided. Cooking
instructions will also be provided where necessary. Food portions should be measured out the
night before and left in the refrigerator overnight.
Foods will be consumed plain or with a set weight of fat (e.g. butter or margarine) or
protein (cottage cheese or tofu). A beverage of their choice (tea or coffee) will also be
taken with either cow or soy milk or water. The quantities should be constant across all test
breakfasts and the total volume of the beverage should be 300 ml.
Foods A list of foods, portion sizes, preparation instructions and order in which to eat them
will be provided prior to the start of the study.
Study test diary form Forms on which to record timing and study details (cooking instructions
for lentils, pasta etc.) will be provided for each test.
Scales and measuring jugs Where possible participants should ensure that they have electronic
scales with wall plugs that are in gram weights and also jugs with ml volume calibrations.
