Skip to Content
A dose-response study to assess the effects of pine bark extract (EnzogenolTM) on glycaemic (blood sugar) responses in healthy participants.
Lead investigator: Wen Xin Janice Lim
Contact email: email@example.com
My name is Janice Lim, and I am a PhD student at Massey University, School of Health
Sciences. My supervisors are A/Prof Rachel Page (Main), A/Prof Pam von Hurst and Dr
You are invited to take part in a dose-response study to assess the effects of pine bark
extract (EnzogenolTM) on glycaemic (blood sugar) responses in healthy participants.
Whether or not you take part is your choice. If you don’t want to take part, you don’t have to
give a reason. If you do want to take part now, but change your mind later, you can pull out
of the study at any time.
This Participant Information Sheet will help you decide if you’d like to take part. It sets out
why we are doing the study, what your participation would involve, what the benefits and
risks to you might be, and what would happen after the study ends. We will go through this
information with you and answer any questions you may have. You do not have to decide
today whether or not you will participate in this study. Before you decide you may want to
talk about the study with other people, such as family, whānau, friends, or healthcare
providers. Feel free to do this.
If you agree to take part in this study, you will be asked to sign the Consent Form. You will
be given a copy of both the Participant Information Sheet and the Consent Form to keep.
This document is 6 pages long. Please make sure you have read and understood all the
Obesity and diabetes are epidemic in New Zealand (and in other Western countries), and
many individuals now have problems controlling their blood sugar levels within normal
Foods are ranked, nowadays, based on their effects on blood sugar levels and this is termed
the glycaemic index (GI) of the food. Generally, lower GI foods are recommended for those
with glucose (sugar) intolerance; however the reality is that typical New Zealand diets are
high in high-GI sugars and processed foods with the average person now consuming an
extra 22 teaspoons of sugar a day.
Certain foods and extracts, including berries, teas and French pine bark extracts have been
shown to reduce blood sugar levels. Data suggests that this may be due to the high levels of
antioxidants that are present in these foods, though other substances may also be involved.
The effects of New Zealand pine bark extract on blood sugar levels has not been studied,
thus this study aims to measure whether blood sugar levels can be reduced in healthy
participants when taking a pine bark extract capsule along with a sugary drink.
This study is a placebo-controlled, blinded, crossover, dose-response study. A placebo-controlled
study means that you will also take part in the control session where a placebo
capsule will be consumed along with a sugary drink to examine the response of your blood
sugar without the active ingredient. A blinded study means that you will not know what type
and concentration of the capsule you will be having. A crossover study means that you, the
participant, serves as your own control where you will take part in both the control visit as
well as all the test visits with the pine bark extract. Any difference in the results between
your control and test visits can thus be attributed to the effects of pine bark extract alone. A
dose-response study means that you will be having various concentrations of the pine bark
extract and your blood sugar response to them during the study.
The study is funded by NZ ENZO Nutraceuticals Ltd and the pine bark extract (Enzogenol)
that will be given to you during the test sessions are provided by NZ ENZO Nutraceuticals
Ltd. The pine bark extract is available for sale in NZ and approved as a food supplement in
NZ and overseas. According to Regulatory Status of Enzogenol in New Zealand, Enzogenol,
a Pinus radiata bark extract, is classified as a dietary supplement.
You have been chosen to participate in the study because you have met the criteria to be
included in the study. The criteria includes:
The study will involve you coming to the Massey University Nutrition Research Facility,
located at Albany campus, North Shore. If you are eligible after the screening visit, you will
need to be available for FIVE different mornings during a six to eight week study period.
Each visit will take approximately 2.5 hours from 7 -7:30 am – 9:30 -10:00 am in the
morning, except for the screening visit. Each session, including the screening visit, will
require you to fast overnight (i.e. no food or drink except water) for at least 10 hours before
coming to the research facility.
What happens during the Screening visit (Visit 1)
During an initial screening session we will assess whether you fit these inclusion criteria.
You will be required to arrive at the research facility at 7:30am ONE morning after at least a
10-hour overnight fast, to have a screening blood sample collected. The session will take
approximately less than an hour. A qualified phlebotomist will measure your fasting blood
sugar, lipid profile and HbA1c levels (the latter is a measure of how stable your blood sugar
levels have been over the last three months) to check that you are not pre-diabetic. If your
results come back and indicate that you have glucose tolerance issues you will NOT be able
to participate. With your permission, we will refer you to your GP for follow-up and you may
show them your blood sugar level results.
In addition, trained researchers will determine your body mass index (BMI) by measuring
your weight and height. They will also be taking your waist and hip circumference, and also
your percentage of body fat and lean body mass (as measured by a bioelectrical impedance
scale). This can be done privately and you do not need to undress. Blood pressure and
heart rate measurement will also be taken. You will also be asked about your medical
history, and any medication use.
During the test visits (visits 2-6), one or two finger-prick blood samples will be taken to
measure your baseline blood sugar level. You will then be asked to consume a capsule
either containing 50, 100, 200 or 400 mg, or a control capsule made of microcrystalline
cellulose. After 20 minutes you will have another baseline finger prick. You will then be
asked to consume a sugar drink of 300 mL containing 75 grams of carbohydrates. You will
need to remain in the research facility for the next two hours and not undertake any physical
activity. Study and quiet activities are allowed, as are trips to the bathroom. Further finger
prick tests will be taken at 15, 30, 45, 60, 90 and 120 minutes after consuming the sugary
drink, and the blood sugar levels recorded. At the completion of this period you are welcome
to eat and drink as normal (this will be provided). We will have DVDs available for viewing
also to help pass the time.
You will be asked to keep your diet and lifestyle as constant as possible throughout the
study and to refrain from engaging in any strenuous physical activity (walking is fine) or
consumption of alcohol in the 24-hour period prior to each study session. Furthermore, avoid
caffeine products (coffee, tea, coke, energy drinks, or chocolates etc.) from noon on the day
prior to your study session. You will also be asked to avoid the active test foods/extracts
(pine bark extract) for at least seven days prior to the first study session and throughout the
duration of the study period (including avoiding other teas and formulations where the pine
bark extract may be present).
Research is a big part of medicine and healthcare and being involved can be very
rewarding. You can learn a lot about the processes that are involved in research by actively
participating and it can be satisfying to know that you are contributing to knowledge.
Furthermore, by participating in the study you also obtain information about your general
health status, HbA1c value, body composition and blood pressure measurement entirely at
no cost to you.
In addition, there will be a reimbursement for involvement in the study.
It is highly unlikely that you will be injured during this study. Finger prick blood sampling is
safe and routinely used. A registered personnel will be available during each study session
and researchers will be present to assess for adverse events (i.e. feeling nauseous,
dehydrated or faint) during each blood sampling, and any event will be documented in
alignment with Massey Code of Ethical Conduct. Furthermore, the pine bark extract has
been tested previously and recorded as safe for consumption by the US FDA.
There is no cost to you, the participant, for taking part in this study.
In recognition of your time and participation in this study, you will be reimbursed $20 for
screening and $30 for completion of each session. You will be reimbursed a total of $170 for
completing the whole study (1 screening visit and 5 study visits) in the form of a gift voucher.
If for any reason you are unable to complete the study, you will be reimbursed for your total
time contributed to the study.
If you were injured in this study, which is unlikely, you would be eligible for compensation.
The study is insured by Chubb Insurance New Zealand Limited. If your claim is accepted,
you will receive funding to assist in your recovery.
If you have private health or life insurance, you may wish to check with your insurer that
taking part in this study won’t affect your cover.
Participating in this study is completely voluntary and you are free to decline to participate,
decline to answer any particular question, or to withdraw from the research at any
practicable time, without experiencing any disadvantage.
You, the participant has a right to access information about you, collected as part of this
study. You will be told of any new information about adverse or beneficial effects related to
this study which may impact upon your health.
It is important to us that we maintain your privacy throughout this study. Your name and
contact information will be held electronically and stored on the Principal Investigators
computer only for data recording purposes. Each participant in the study will be allocated a
number. Staff involved in blood sampling and analysis will have access to participant
numbers only. All data from study sessions will be recorded against your participant ID
number and your name will never be used in any report, correspondence or publication.
Your involvement in this study is confidential.
You are able to pull out of the study at any time, and will be compensated accordingly for
your time. Further you are welcome to discuss any concerns you have with the research team at any time, and you have free access to your data. If you pull out of the study all of the
data that was related to you will be shredded. The treatment intervention (pine bark extract) will not be available to any participant after the
The study data will be stored at a secure location at Massey University Albany Campus.
Electronic data and records will be the responsibility of the Principal investigator. All data will
be kept for 7 years, at which point it will be destroyed using University Security methods for
removal of confidential material.
Participants are welcome to discuss the findings of this study with the researchers at any
time. You will also be provided with a full copy of the final study report, if requested.
It is very likely that the results of this study will be written up for publication in a peer-reviewed
journal and/or presentation and a Nutrition conference within 12 months of
completing the study. If this happens no participant identification information will be included.
If you have any questions, concerns or complaints about the study at any stage, you can
contact the following researchers involved in the study:
Dr Lynne Chepulis: Senior Research Fellow, Medical Research Unit, University of Waikato,
Phone: +64 (07) 3468754
A/Prof Rachel Page: Head of School of Health Sciences
Phone 0800 627739 ext. 63462
A/Prof Pam Von Hurst: Associate Professor, School of Sport, Exercise and Nutrition,
Massey University, Albany
Phone: +64 (09) 2136657
Wen Xin Janice Lim: PhD student, School of Health Sciences, Massey Institute Food
Science & Technology, Albany
You may also contact the Massey University Human Ethics Committee (MUHEC) involving
any concerns that you may have:
This project has been reviewed and approved by the Massey University Human Ethics
Committee: Southern A, Application 17/73. If you have any concerns about the conduct of
this research, please contact Dr Lesley Batten, Chair, Massey University Human Ethics
Committee: Southern A, telephone 06 356 9099 x 85094, email
Page authorised by Head of School, School of Food and Nutrition
Last updated on Thursday 22 March 2018