Impact of a Low-carbohydrate Versus Low-fat Breakfast on Blood Glucose Control in Type 2 Diabetes
Phase: NA
Conditions: Dietary Habits
Sponsor: University of British Columbia

 
 
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Faculty of Health and Social Development 
School of Health and Exercise Sciences 
3333 University Way 
Kelowna, BC  V1V 1W5 
Title: Impact of a low-carbohydrate versus low-fat breakfast on blood glucose control 
in type 2 diabetes 
 
Research Question: Does a low-carbohydrate breakfast impact blood glucose 
levels in people with type 2 diabetes? 
 
Objectives 
1) To determine whether a low-carb high-fat (LCHF) breakfast, compared to 
a standard control low-fat (CTL) breakfast impacts haemoglobin A1c 
(HbA1c; the clinical marker of glucose control) in individuals with T2D;  
2) To evaluate if compared to a low-fat breakfast, a low-carb high-fat breakfast 
influences satiety and daily caloric intake in individuals with T2D;  
3) To determine whether a low-carb high-fat breakfast, compared to a 
standard control low-fat breakfast alters body weight in individuals with 
T2D; 
4) To determine whether a low-carb high-fat breakfast alters glucose levels, 
blood lipid profile and inflammation biomarkers compared to a low-fat 
breakfast in individuals with T2D; 
5) To verify if compared to a low-fat breakfast, a low-carb high-fat breakfast 
raises lutein levels and improves cognition in individuals with T2D. 
 
 
Hypothesis: 
a) A low-carb high-fat breakfast, compared to a standard control low-fat 
breakfast will reduce HbA1c levels 
b) When compared to a low-fat breakfast, low-carb high-fat breakfast will 
improve satiety and lower daily caloric intake. 
c) Compared to a low-fat breakfast, a low-carb high-fat breakfast will lower 
body weight in individuals with T2D; 
d) A low-carb high-fat breakfast will improve glucose levels, blood lipid profile 
and inflammation biomarkers compared to a low-fat breakfast in individuals 
with T2D; 
e) Compared to a low-fat breakfast, a low-carb high-fat breakfast will raise 
lutein levels and consequently improve cognition functions.  
 
 
 
Background Information 
 
Diabetes is a rapidly growing public health problem worldwide. Among adults aged 
20–79 years in 2017 there was an estimated 425 million cases of diabetes. Over 
90% of these have type 2 diabetes (T2D); a chronic, progressive condition that is 
characterized by profound insulin resistance and pancreatic beta-cell dysfunction 
that leads to elevated blood glucose levels [1]. Chronically elevated blood glucose 

 
 
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(i.e., hyperglycemia) contributes to the devastating complications of T2D, including 
cardiovascular disease, retinopathy, and neuropathy [2].  
More than 100 million U.S. adults are now living with diabetes or prediabetes, 
according to a report released by the Centers for Disease Control and Prevention 
(CDC) [3]. In 2015, 30.3 million Americans, or 9.4% of the population, had 
diabetes. Another 84.1 million have prediabetes, a condition that if not treated often 
leads to type 2 diabetes within five years. Diabetes was the seventh leading cause 
of death in the U.S. in 2015. The total estimated cost of diagnosed diabetes in 
2017 is $327 billion, including $237 billion in direct medical costs and $90 billion in 
reduced productivity [3].  Clearly, strategies to improve glucose control and reduce 
the burden of T2D are attractive from a quality of life and economic standpoint.   
In T2D, consuming carbohydrates results in a rapid and large increase in blood 
glucose. Accumulating evidence indicates that these postprandial “hyperglycemic 
spikes” are particularly important in driving the pathophysiology of diabetes 
complications. Postprandial hyperglycemia is an independent risk factor for 
cardiovascular disease and mortality [4] and lowering postprandial glucose spikes 
can reduce the risk of cardiovascular disease [5]. The highest hyperglycemic spike 
often occurs after breakfast, leading to the largest excursion of the day and thus 
breakfast is a crucial barrier preventing good glycemic control [6]. Lowering post-
breakfast hyperglycemia therefore represents a key treatment opportunity for 
people with T2D. 
 
Although we are unaware of any long-term (i.e. weeks/months) low-carbohydrate 
egg-based breakfast trials, previous studies have supported possible benefits of 
manipulating breakfast composition in order to improve blood glucose control and 
other health outcomes relevant to people with, or at risk for, T2D. Pedersen et al.   
[7] confirmed that in T2D, excluding carbohydrate from the first meal of the day 
could blunt the large breakfast glucose spike. Park et al. [8] showed that a high-
protein breakfast lowers postprandial glucose concentrations at this meal and does 
not magnify the glucose response to the second meal, suggesting that adding 
protein to breakfast could be a therapeutic option for T2D. Over the longer-term, 
consuming a “big breakfast” containing higher fat and protein that provided 33% 
total daily energy over 3 months led to a significant reduction in HbA1c (the main 
clinical marker of glucose control that reflects average blood glucose levels over 
the previous 90-120 days) when compared to a small breakfast providing 12.5% 
daily energy [9]. Thus, previous research suggests that manipulating breakfast 
composition can have potential benefits for people with T2D.  
Targeting the meal that leads to the largest glucose spike may be a simple, feasible 
strategy to improve glycemic control and reduce risk for future diabetes 

 
 
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complications. One strategy to eliminate this large hyperglycemic excursion is to 
consume an LCHF breakfast. Epidemiological studies report that the routine 
consumption of a LCHF breakfast could be beneficial for reducing the risk of T2D, 
cardiovascular disease, and other chronic diseases [10]. Recent experimental 
work from our lab published in the American Journal of Clinical Nutrition [11] shows 
a 74% reduction in 24-hour postprandial hyperglycemia with a LC breakfast (egg 
and cheese omelet) when compared to a standard low-fat breakfast (oatmeal with 
berries) in people with T2D. Consuming a low-carbohydrate high-fat breakfast 
could be a simple strategy to prevent the largest post-breakfast glucose spike and 
improve overall glucose control in T2D. 
The potential benefits of a low-carbohydrate breakfast compliments previous 
research examining the impact of high-protein breakfasts. It has been 
demonstrated that the daily consumption of a high-protein rather than a high-
carbohydrate breakfast prevented the gain in body fat, and caused reductions in 
daily hunger and daily food intake [9] [12] [13] [14] [15]. Indeed, in our recent study 
[11] we saw that consuming the LC breakfast (which was high in protein) led to 
lower feelings of hunger and desire to eat sweet “junk” foods later in the day.  
 
Low-carb high protein breakfast are usually composed of eggs and bacon. Eggs 
contain a variety of essential nutrients that can impact human health. Egg yolks 
contain various antioxidant carotenoids. Among them, lutein and zeaxanthin are 
the only two that cross the blood-retina barrier to form macular pigment in the eye, 
and lutein is the dominant carotenoid in human brain tissue. In people with T2D, it 
is important to minimize progressive complications of the disease including 
cognitive impairment, macular degeneration and retinopathy. Lutein is increasingly 
recognized as having a role in cognitive function. The possibility of a low-carb high-
fat breakfast with eggs having nutritional benefits that advance beyond regular 
metabolic control in T2D to influence the brain and eye is intriguing. [16] [17] [16] 
[17] 
 
 
Taken together, our recently published work on improved glycemic control and 
reduced hunger with a low-carbohydrate breakfast in T2D patients [11] coupled 
with studies showing that high-protein breakfasts can have health benefits in T2D, 
provide strong rationale for a properly powered longer-term randomized controlled 
trial (RCT) to determine if regular consumption of a LCHF breakfast can lead to 
clinically important improvements in glycemic control and health markers in 
individuals with T2D. We hypothesize that consuming a LCHF breakfast will 
improve blood glucose control, increase satiety and improve body 
composition, as well as cognitive function in people with T2D. This 

 
 
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information will provide high quality scientific evidence for the potential health 
benefits of reducing carbohydrates at breakfast as a dietary strategy for managing 
T2D. The proposed RCT will significantly advance the existing evidence that has 
shown contribution of a LCHF consumption in improving body composition in T2D 
[15] by strategically incorporating a low-carbohydrate high-fat breakfast to test 
whether it can lower HbA1c, the key clinical treatment outcome in T2D. The 
findings will be easy-to-implement and could help solidify LCHF as the ideal 
breakfast option for people with T2D. 
 
Research Method 
 
Eighty-two (N=82) individuals between University of British Columbia and 
University of Wollongong, Australia with physician diagnosed T2D (HbA1c < 
8.5%), between the ages of 20-79 years, with a BMI above 25 kg/m2 will be 
recruited through online social media and newspaper advertising. REACH BC and 
Trialfacts will assist with recruitment. REACH BC is an initiative of BC’s health 
authorities and partner universities bridging the gap between the public and 
researchers. Trialfacts combines extensive marketing and advertising expertise 
with in-depth clinical trial experience to create effective marketing solutions. We 
have a partnership with the Kelowna Diabetes Program to assist recruiting from 
>6500 well-monitored T2D patients in our region.  
Inclusion criteria will be: i) physician-diagnosed T2D of ≥1 year; ii) current HbA1c 
of <8.5%; iii) BMI:  higher than 25kg/m2; iv) blood pressure of <160/99 mm Hg 
assessed according to guidelines; v) non-smoking; vi) not on hormone 
replacement therapy, corticosteroids, or anti-inflammatory medications; and vii) 
20–79 years old. Exclusion criteria will include: i) Use of exogenous insulin; ii) 
taking more than 2 glucose lowering medications; iii) ongoing medical treatment 
for diseases such as cancer, auto-immune or inflammatory disease, liver or kidney 
disorders; iv) allergy, intolerance or aversion to eggs or any other dietary 
restrictions (e.g., vegan, breakfast skipping) that will prevent them from following 
the standardized study diets;  v) being unable to follow remote guidance by internet 
or smartphone; vi) being unable to follow the controlled diet instructions;. 
Based on our previous studies ~55% of males and ~70% of females with T2D who 
volunteer will meet these eligibility criteria so we anticipate no recruitment issues. 
We will allow statins and anti-hypertensive medications if on a stable dose for 3 
months because the majority of T2D patients are on at least one of these 
medications; excluding them would leave a small pool for recruitment and limit the 
generalizability of our findings.  
 
A 3-month parallel-group randomized controlled trial is proposed. Eligible 
participants will be randomized to either the Low-carb High-fat breakfast (LCHF, 
n=41) or a low-fat “standard care” control breakfast (CTL, n=41), to be consumed 
daily for a period of 3 months.  

 
 
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Due to COVID-19 breakout, this study is proposed to be done remotely since 
participants belong to risk group and will probably maintain in quarantine for 
unpredictable time. Information and guidance for the trial will be done by email, 
telephone calls and text messages. RedCap-UBC will be used to manage 
information and deliver questionnaires. 
Each group will be provided with a menu of 8 LCHF breakfasts or 8 CTL breakfasts 
from which to choose each morning. Breakfast options (designed by Dr. Barbara 
Oliveira, Registered Dietitian) will be controlled in macronutrient content and 
calories (~400-500 kcal), but allow for personal preference and autonomy to 
promote adherence. Instruction will be given for digital recording of breakfast by a 
RedCap-UBC link sent by email. Participants will also be guided to register three 
3-day food records (2 weekdays and 1 weekend day) at weeks 1, 6 and 12 of the 
trial using a diet logbook provided. Reminders to complete the 3-day food records 
and app will be given by telephone call, text messages and/or emails based on 
participant preference. We have used this approach successfully in several recent 
and ongoing trials [18] [19].  
The Godin Leisure-Time Exercise Questionnaire will allow the assessment of self-
-‐reported leisure--‐time physical activity. The individual is asked to complete a 
self-explanatory, brief four-item query of usual leisure-time exercise habits at 
weeks 1, 6 and 12 of the trial. 
Participants will complete 100 mm Visual Analog Scales (VAS) to measure self-
reported hunger, fullness before each meal (breakfast, lunch and dinner) at weeks 
1, 6 and 12 of the trial.  
A cognition test will be performed at weeks 0, 6 and 12 by an online link provided 
to participant to be answered at home.  
Before and after the 3-month intervention, an 8-10 hour fasting blood sample will 
be obtained. For the primary outcome, HbA1c participants will be asked results 
from a recent exam (less than 1 month old). If results are not recent, participants 
will be asked to go to a local laboratory for a new test. Participants with high levels 
of A1c (>8.5%) during screening will be notified via email and not eligible for the 
study. Secondary outcomes of fasting plasma glucose, insulin, blood lipid profile 
(triglycerides, total, HDL, and LDL cholesterol), carotenoids (lutein and zeaxanthin) 
and inflammation (high-sensitivity C-reactive protein [CRP] will be measured by a 
dried blood spot test. Dried blood spot is a form of collection where patients place 
blood drops on a filter card after a finger prick with a lancet. Once dry, blood spot 
cards are extremely stable for shipment and storage, and the dried blood format 
offers excellent correlation with serum tests. It offers distinct advantages because 
it eliminates the need for a blood draw and translocation – reducing patients 
burden. 
 
A CGM device (Abbott FreeStyle Libre) will be inserted to participants’ upper arm 
in order to collect continuous glucose readings during the first and last 14 days of 
the trial. CGM will serve to confirm that the LCHF meal lowers the post-breakfast 

 
 
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glucose spike and will provide details on daily postprandial hyperglycemia to be 
used in analyses of overall glucose control (24 h average, post-meal areas under 
the curve [AUC], and glycemic variability).  
 
Self-reported weight and height will be registered at the beginning and end of the 
study.   
 
 
Study Timeline:  
 
1. Baseline contact 
2. Day 0 
3. Day 1 
4. Day 7 
5. Day 14 
6. Day 21  
7. Day 42 
8. Day 84 – End of study  
Timeline:  
 
Baseline Contact 
 
Participants will be recruited by email, online recruitment (including REACH BC 
and Trialfacts) or telephone call. Screening will be confirmed by filling out a Health 
Screening form and signing an electronic Consent form through a RedCap-UBC 
link. The postdoctoral fellow research lead (Dr. Barbara Oliveira) will ensure that 
the subjects understand the details of the study and consent form. After 
confirmation, participants will receive a study kit at their homes containing the 
following: 
 
- 
Study Welcoming, Instructions and Responsibilities 
- 
2 Dry blood spot kit (beginning and end of study) 
- 
Recipe book 
- 
Controlled Glucose Monitor (CGM) Reader and sensor 
- 
Food coupons and gift card 
 
 
Instructions will consist of: 
- 
A schedule and timeline of the study with participants’ responsibilities; 
- 
Instructions on Diet Habit Survey;  
- 
A menu and preparation of 8 LCHF breakfasts or 8 CTL breakfasts recipes 
from which to choose each morning; 
- 
How to send digital recording of breakfast by RedCap link;  

 
 
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- 
Guidance in registering three 3-day food records (2 weekdays and 1 
weekend day) at weeks 1, 6 and 12 of the trial using an online diet logbook;  
- 
How to answer questionnaires for self-reported hunger and fullness to be 
completed before each meal (breakfast, lunch and dinner) and a physical 
activity questionnaire (GODIN) at weeks 1, 6 and 12; 
- 
How to complete the cognition test at day 0, day 42 and day 84; 
- 
Blood collection instructions with link to explanatory video. 
Day 0 
✓ Diet Habit Survey; 
✓ TPB questionnaire; 
✓ Baseline Cognition test;  
✓ HbA1c results: participants should have a recent (less than 1 month from study 
start) HbA1c test or head to local lab for testing. 
Diet Habit Survey will be answered by a link sent to participants through RedCap-
UBC. 
 
Cognition test will be sent as a link to be answered in a quiet room. Tests will last 
approximately 10 minutes.  
 
Day 1 
 
✓ Blood sample collection 
✓ Insert CGM 1 
 
Blood drops will be collected by participants after having fasted overnight (8-10 h) 
and refrain from taking any medications on the morning to measure the primary 
outcome of HbA1c and associated secondary outcomes measures of fasting 
plasma glucose, insulin, blood lipid profile and inflammation. Envelope will be then 
sent to research team by mail.  
 
CGM instructions will also be sent and a Zoom meeting can be scheduled to help 
participants with insertion of device. 
 
Day 7 
 
✓ Self-reported Hunger and Fullness Questionnaire 
✓ GODIN Physical Activity Questionnaire 
✓ Diet Food log 
Day 14 
 
✓ Remove CGM 1 and send by mail 
Day 21 – Follow-up 

 
 
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Research team will contact participants to follow-up on study and verify compliance 
to breakfast recipes as well as provide new ideas and guidance on possible issues.  
 
Day 42 
✓ Self-reported Hunger and Fullness Questionnaire 
✓ GODIN Physical Activity Questionnaire 
✓ Cognition Test  
✓ Food log 
Day 70 
 
✓ Insert CGM 2 
 
Day 84 
 
✓ Self-reported Hunger and Fullness Questionnaire 
✓ GODIN Physical Activity Questionnaire 
✓ Cognition Test 
✓ Food log 
✓ TPB questionnaire 
✓ Provide self-reported weight.  
✓ Blood sample collection. Blood drops will be collected by participants after 
having fasted overnight (8-10 h) and refrain from taking any medications on 
the morning to measure the primary outcome of HbA1c and associated 
secondary outcomes measures of fasting plasma glucose, insulin, blood 
lipid profile and inflammation. Envelope will be then sent to research team 
by mail. 
✓ Remove CGM 2 and send by mail. 
✓ Cognition test. Cognition test will be sent as a link to be answered in a quiet 
room. Tests will last approximately 10 minutes.  
✓ End of study Survey 
✓ HbA1c results: participants should have a recent (less than 1 week from study end 
date) HbA1c test or head to local lab for testing. 

 
 
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Statistical Analysis 
 
This study will be reported according to the CONSORT 2010 statement for RCTs. 
Data will be analyzed on an intention-to-treat basis. Descriptive statistics (means, 
SD, and frequencies) will be calculated. Histograms and Q-Q plots of residuals will 
be used to identify any outliers and to test for normality. The primary outcome of 
HbA1c will be analyzed by linear mixed effects regression to assess differences 
between groups, with age and sex included in the model. Secondary outcomes will 
be analyzed similarly. Data with skewed distributions will be log-transformed prior 
to statistical testing or non-linear mixed effects regression will be performed. All 
participants will be included in the intention-to-treat analyses and missing data will 
not be imputed, per contemporary guidelines with use of linear mixed models.  
 
Sample size 
We used a previous breakfast intervention in T2D along with our recently published 
one-day egg-based LC breakfast trial to calculate sample size for this RCT. 
Rabinovitz et al. [9] compared a “big breakfast” containing higher fat and protein 
providing 33% total daily energy to a small breakfast providing 12.5% daily energy 
over 3 months in a similar sample of participants with T2D using a similar parallel-
group design. They reported an absolute reduction in HbA1c% of 0.46%. This is 
similar to the magnitude of change observed in a recent study by Nichols et al. [20] 
who reported an average HbA1c reduction of 0.45% in response to metformin, the 
standard prescribed medication for people newly diagnosed with T2D. For this 
reason, it is reasonable to use the study published by Rabinovitz et al. to estimate 
a clinically relevant effect size in our sample size calculation. A medium effect size 
(Cohen’s d = 0.46) was calculated from the Rabinovitz study. In agreement, for our 

 
 
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recent one-day study examining an egg-based LC breakfast [11], the effect size 
(Cohen’s d) for improvements in CGM-derived glucose control variables (including 
AUC, iAUC, glycemic variability, and mean) ranged from d = 0.48-1.2. 
Taking a conservative approach, we used an effect size of d = 0.4 in the sample 
size calculation. The total sample size necessary to detect a between-within 
interaction using repeated measures ANOVA with an effect size of d = 0.4 (which 
corresponds to an ANOVA effect size f = 0.2) with 90% power and 5% type 1 error 
with a conservative correlation among repeated measures of r=0.5 is 68 (n=34 per 
group, calculated using G*Power v3.1.9.2). To account for a 20% dropout rate [9] 
we will recruit a sample size of n=41 per group. 
 
Significance 
 
The results of this study will help determine whether by consuming a Low-carb 
High fat breakfast people with T2D will improve blood glucose control, increase 
satiety and improve body composition. This information will provide high quality 
scientific evidence for the potential health benefits of consuming a low-
carbohydrate breakfast, as a dietary strategy for managing T2D.  
 
 
 
OUTCOMES MEASUREMENTS AND METHODS 
 
The primary outcome measure is HbA1c concentrations over the 12 week period 
following the LCHF breakfast or the CTL breakfast. Secondary measures will 
include plasma glucose, insulin, blood lipid profile (triglycerides, total, HDL, and 
LDL cholesterol) and inflammation (high-sensitivity C-reactive protein [CRP], 
tumour necrosis factor [TNF]-alpha, interleukin [IL]-6). As well as hunger/satiety 
levels, caloric intake and body weight/ body fat mass outcomes.  
 
 
Dietary assessment 
 
Each group will be provided with a menu and preparation instructions consisting 
of 8 ~400-500 kcal LCHF breakfasts (<10% carbohydrates, 65-75% fat, and 15-
25% protein; e.g., omelet including low-carbohydrate additions such as cheese, 
meat, or non-starchy vegetables) or 8 ~400-500 kcal CTL breakfasts (45-60% 
carbohydrates, 20-35% fat, 15-25% protein – according to Diabetes Canada 
Clinical Practice Guidelines, 2018; e.g., oatmeal and berries) from which to choose 
each morning. Meals will be matched in calories (~400-500kcal) and protein 
content (15-25%). Instruction will be given for digital recording of breakfast by 
RedCap-UBClink. Participants will also be guided to register three 3-day food 
records (2 weekdays and 1 weekend day) at weeks 1, 6 and 12 of the trial using a 
logbook provided with instructions by the research team at initial consultation. 
Reminders to complete the 3-day food records will be given by telephone call, text 

 
 
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messages and/or emails based on participant preference. We have used this 
approach successfully in several recent and ongoing trials [18] [19]. Macronutrient 
composition and total caloric intake will be calculated using FoodWorks (The 
Nutrition Company) software to determine any group differences across time. 
Participants will complete 100 mm Visual Analog Scales (VAS) to measure self-
reported hunger, fullness and desire for sweet and savoury foods before each meal 
(breakfast, lunch and dinner) at weeks 1, 6 and 12. Participants will rate each of 
the following 4 questions by marking vertically on a horizontal line with descriptive 
anchors on either side (“not at all” to “extremely”): 1) How hungry do you feel; 2) 
How full do you feel; 3) How satisfied do you feel; 4) How much do you think you 
can eat? The VAS scores will be converted to a 0–100 scale, as previously 
described [21]. We used this approach in our supporting preliminary study [11] 
showing reduced pre-dinner hunger when a LCHF breakfast was consumed by 
people with T2D. Questionnaire is included as attachment and will be sent as link 
from the RedCap platform.  
 
The Godin Leisure-Time Exercise Questionnaire allows the assessment of self--‐
reported leisure--‐time physical activity. The individual is asked to complete a self-
explanatory, brief four-item query of usual leisure-time exercise habits. The leisure-
-‐time physical activity score is expressed in units and can be computed in two 
steps. First, weekly frequencies of strenuous, moderate, and mild   activities are 
multiplied by nine, five, and three, respectively; these three latter values 
correspond to MET (metabolic equivalents) value categories of the activities listed. 
Then, the total weekly leisure activity score is computed in arbitrary units by 
summing the products of the separate components. Questionnaire is included as 
attachments and will be sent as link from the RedCap platform. 
 
Cognition test 
Questionnaire is included as attachments and will be sent as link from the RedCap 
platform. 
 
TPB Questionnaire 
Questionnaire is included as attachments and will be sent as link from the RedCap 
platform. 
 
Blood samples 
Blood will be collected at 2 timepoints, one at baseline and the other at the end of 
the trial. For the primary outcome of HbA1c, participants will be asked for results 
from a recent HbA1c test in 2 time points: a) less than a month from study start 
and b) less than one week from study end. If they a recent exam is not available, 
participants will be asked to go to their nearest local lab for a recent HbA1c blood 
test. They will receive a requisition by e-mail and will not need to pay or have a 
doctor’s referral for the exam. Participants with high levels of A1c (>8.5%) during 
screening will be notified via email and not eligible for the study. For secondary 

 
 
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outcomes, a dried blood spot device will be used for sampling. Dried blood spot is 
a form of collection where patients place blood drops on a filter card after a finger prick 
with a lancet. Once dry, blood spot cards are extremely stable for shipment and 
storage, and the dried blood format offers excellent correlation with serum tests. The 
same laboratory providing the blood spot will analyze primary outcome of HbA1c and 
associated secondary outcomes measures of fasting plasma glucose, insulin, 
blood lipid profile (triglycerides, total, HDL, and LDL cholesterol) and inflammation 
(high-sensitivity C-reactive protein [CRP]).  
 
Continuous Glucose Monitoring (CGM) 
A CGM device (Abbot FreeStyle Libre PRO) will be inserted into the subcutaneous 
adipose tissue of the participants’ upper arm in order to collect continuous glucose 
readings during the first and last 2 weeks (14 days) of the trial. CGM sensor 
glucose readings are taken from the interstitial fluid (ISF), a thin layer of fluid that 
surrounds the cells of the tissues below the skin. The FreeStyle Libre PRO device 
is factory-calibrated so requires no finger stick calibrations (which reduces 
participant burden) and is indicated for detecting trends and tracking patterns of 
hyperglycemia and hypoglycemia. CGM will serve to confirm that the LCHF meal 
lowers the post-breakfast glucose spike and will provide details on daily 
postprandial hyperglycemia to be used in analyses of overall glucose control (24 
h average, post-meal areas under the curve [AUC], and glycemic variability). The 
research team is experienced in CGM data collection and analyses having 
conducted >10 CGM-based studies in the last 8 years [11] [16][17] [22] [23].  
 
Dr. Thomas Elliott will be the qualified investigator overseeing the continuous 
glucose monitoring and to whom the CGM devices will be sold as per section 83 
of the Medical Devices Regulations.  
 
Height and weight 
Participants will be asked to report height and weight at the beginning and end of 
the trial. They will be oriented to weigh themselves on the same scale both 
timepoints wearing minimal clothes and at same hour of the day.  
 
Website 
As research shifts to a remote model due to COVID-19, online resources can be 
extremely valuable. Utilization of a website is proposed because it can be cost 
effective, efficient and successful in engaging individuals for initial user feedback, 
recruitment, follow-up and information dissemination. The website consultation 
and log in will not be mandatory. Participants can use it safely as no personal 
information will be collected by navigation. If log in is desired, participants will 
receive a link to create a personal account inputting a log in and password. They 
will then have access to documents, recipes and news. If they do not wish to create 
an account, they will still receive all materials by email. The only personal 
information sent to research team is the email.  
All this information is described on the Terms of Use and Privacy Policy links 
(below) in the website and on Consent Form.  

 
 
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Links with Private Policy and Terms of use: 
 
https://www.ubcbreakfaststudy.com/privacy-policy 
 
https://www.ubcbreakfaststudy.com/terms-of-use 
 
The website was created in a Wix platform. Wix.com is a leading cloud-based 
development platform with millions of users worldwide. Users’ and Users-of-Users’ 
Personal Information may be stored in data centers located in the United States of 
America, Ireland, South Korea, Taiwan and Israel. It may use other jurisdictions as 
necessary for the proper delivery of Services and/or as may be required by law. 
More information on Privacy policy and Terms of use in link below: 
https://www.wix.com/features/main  
 
 
Protection of Human Subjects 
 
All participants will be given a unique study code, with all data and information 
gathered connected with this code. Only the PI will have access to the master list 
linking the codes with participant names. Participant information and data will be 
either stored in a locked filing cabinet, or on an internal UBC network drive 
accessed only through a dedicated LAN internet connection on a password 
protected computer in the PIs laboratory with Salto passcard access only to the 
members of the research lab.  
REDCap will be used as project management, storage of information, sending 
questionnaires and processing results.  The REDCap platform is a secure web 
application for building and managing research data collection instruments. The 
platform is specifically designed to support online or offline data capture for 
research studies. The REDCap platform runs on server infrastructure physically 
located in BC, Canada, at the UBC University Data Centre (UDC).  
If participants perform a HbA1c test at the Laboratory, results will be transmitted 
by secure fax from Laboratory to UBC (fax machine located in PI’s Lab which is 
only accessed by lab members through Salto cards). 
 
 
POTENTIAL PROBLEMS AND ALTERNATIVE STRATEGIES 
Diet compliance: We will encourage accurate recording of diet by providing clear 
instructions and training participants on the necessary detail required. Together 
with the assessment of dislikes and allergies we will personalize each intervention 
diet and provide guidance to enhance compliance, as the recipes provided will be 
allow to choose from personal preference. Participants will complete a food log to 
record consumption of the study diets at specific timepoints (1, 6 and 12 weeks). 

 
 
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School of Health and Exercise Sciences 
3333 University Way 
Kelowna, BC  V1V 1W5 
Since the study involves a minor modification to diet, we do not anticipate that any 
adverse events due to the interventions will be seen. 
 
Blood sampling:  
Blood collection in local labs will follow all safety protocols established by 
laboratory and Public Health Agency of Canada (PHAC), BC-Centre for Disease 
Control, and Interior Health (IH). But, there is the risk of exposure to contamination 
by the Coronavirus. To minimize risks, participants will receive a copy of Lab’s 
Safety information and procedures which include social distancing and face 
covering measures. Blood spots: when compared to traditional wet blood and 
plasma collection using venipuncture, capillary blood sampling is safer and easier, 
so much so that nearly anyone can perform the procedure, mainly type 2 diabetes 
patients who are used to doing finger pricks for glucose levels.  However, risks 
associated with the process of finger-stick blood draws are minimized by usage of 
sterile and disposable material as well as hygiene procedures. Participants will 
receive their own kit with sterile material and instructions on procedure. 
 
Protection of personal data: All participants will be given a unique study code, with 
all data and information gathered connected with this code. Only the PI will have 
access to the master list linking the codes with participant names. Participant 
information and data will be either stored in a locked filing cabernet, or on an 
internal UBC network drive accessed only through a dedicated LAN internet 
connection on a password protected computer in the PIs laboratory with Salto 
passcard access only to the members of the research lab. 
 
If participants perform a HbA1c test at the Laboratory, results will be transmitted 
by secure fax from Laboratory to UBC (fax machine located in PI’s Lab which is 
only accessed by lab members through Salto cards). Exam results will be identified 
only by study identification number. 
 
If participants would like to have access to their partial results, they will opt for that 
on the “End of Study Survey” for an “Individual End of Study Report” that will be 
then sent by email. It will contain participants ID and date of birth (day/month/year) 
plus information from their participation such as pre and post Continuous Glucose 
readings and HbA1c results.  
 
REDCap will be used as project management, storage of information, sending 
questionnaires and processing results.  The REDCap platform is a secure web 
application for building and managing research data collection instruments. The 
platform is specifically designed to support online or offline data capture for 
research studies. The REDCap platform runs on server infrastructure physically 
located in BC, Canada, at the UBC University Data Centre (UDC).  
 
There are no risks and it is not mandatory to visit or log in to website. Most of our 
services do not require any form of registration, allowing participants to visit our 

 
 
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Faculty of Health and Social Development 
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3333 University Way 
Kelowna, BC  V1V 1W5 
site without any identification. However, some services may require personal 
Information such as name and email address. This contact information will only be 
used for the purposes for which it is supplied to us (e.g., responding to comments 
or requests for information). Once consented in the study, participants have the 
option to log in and access study information such as recipes, forms and 
communicate with Research team. This can be done by creating a log in and 
password using the email as the only personal information. Registering in the 
website is not mandatory since all documents will be provided to participants via 
e-mail and in a printed format.   
 
Informed consent and ethics: Prior to beginning the study Informed consent will be 
obtained from participants and they will be informed they can withdraw at any time. 
For participants already enrolled in the study, the updated version will be sent by 
email with new information highlighted. 
Participants who completed the study will be contacted via email asking if they 
would like an “End of Study Report”. If yes, the report will be sent by email.  
 
 
References 
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Punthakee, Z., R. Goldenberg, and P. Katz, Definition, classification and diagnosis of 
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Cavalot, F., et al., Postprandial blood glucose is a stronger predictor of cardiovascular 
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3333 University Way 
Kelowna, BC  V1V 1W5 
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Fuller, N.R., et al., The effect of a high-egg diet on cardiovascular risk factors in people 
with type 2 diabetes: the Diabetes and Egg (DIABEGG) study—a 3-mo randomized 
controlled trial. The American journal of clinical nutrition, 2015. 101(4): p. 705-713. 
14. 
Jakubowicz, D., et al., High-energy breakfast based on whey protein reduces body 
weight, postprandial glycemia and hba1c in type 2 diabetes. The Journal of nutritional 
biochemistry, 2017. 49: p. 1-7. 
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Njike, V.Y., et al., Egg ingestion in adults with type 2 diabetes: effects on glycemic 
control, anthropometry, and diet quality—a randomized, controlled, crossover trial. 
BMJ Open Diabetes Research and Care, 2016. 4(1): p. e000281. 
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Johnson, E.J., Role of lutein and zeaxanthin in visual and cognitive function throughout 
the lifespan. Nutrition reviews, 2014. 72(9): p. 605-612. 
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Andersen, C.J., Bioactive egg components and inflammation. Nutrients, 2015. 7(9): p. 
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Francois, M.E., et al., Combined interval training and post-exercise nutrition in type 2 
diabetes: a randomized control trial. Frontiers in physiology, 2017. 8: p. 528. 
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Myette‐Côté, É., et al., Prior ingestion of exogenous ketone monoester attenuates the 
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Nichols, G.A., et al., The change in HbA1c associated with initial adherence and 
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