Plain English Summary
Background and study aims
‘Whole grains are good for you’. This is the message currently given by health professionals, nutritionists and, increasingly, food manufacturers worldwide. They make this statement after careful consideration of a large amount of evidence from studies of populations carried out over many years. These observational studies include information gathered from many thousands of people where diet is measured and later health outcomes are recorded. These studies are often used by governments and health agencies to develop health eating advice for the population. The results from these studies show strong associations between whole grain intake and health; those that eat the most whole grains are less likely to suffer from heart diseases, some cancers and to develop Type 2 diabetes compared with those who eat the least amount of whole grains. The government in America thinks that this evidence is so strong that it now advises its citizens to ‘eat at least three servings of whole grain’ every day. Some foods containing whole grain in America and Europe (including Britain) can show a health claim promoting the foods as being ‘good for your heart’. The problem with observational studies is that they are good at showing relationships between diet and health, but they do not say why this effect is seen. Also, other factors such as whether subjects smoke, or do more exercise, or eat lots of other healthy foods can complicate the interpretation of the results. To really show whether a particular type of food or diet pattern is of benefit and why, we need to carry out interventional studies. These are studies where volunteers are asked to change their diet for a period of time (normally several weeks or months) and scientists look for changes in markers which are known to be related to disease risk. The role of the Food Standards Agency is to provide, interpret and disseminate information which can be used to help the UK population to live longer, healthier lives. Diet is very important in this context. If the Agency is to give advice on whether or not it should recommend we eat more whole grains it needs scientific evidence based on well designed dietary interventions. The aim of this study is to find out whether eating wholegrain foods results in reduced heart disease risk, to provide evidence for future dietary recommendations.
Who can participate?
Overweight but otherwise healthy people, aged 30-65.
What does the study involve?
Participants are randomly allocated to one of three groups. One group is asked not to change their diet and to carry on as normal. The second group is asked to eat three servings of wholegrain food (which we provided) every day for 16 weeks – this is the amount recommended by the American health agencies. The third group is asked to eat this amount for 8 weeks and then to double the amount to six servings of whole grain per day for the final 8 weeks. At the start of the study and after 8 and 16 weeks the participants are weighed and measured and provide blood and urine samples. At week 4 and 12 of the study the participants also give another small urine sample. We measure the diet of the participants at the same time points using a questionnaire. After the study has finished some of the participants attend a focus group meeting to discuss their experiences.
What are the possible benefits and risks of participating?
Not provided at time of registration
Where is the study run from?
University of Newcastle upon Tyne (UK)
When is the study starting and how long is it expected to run for?
July 2005 to April 2007
Who is funding the study?
Food Standards Agency (UK)
Who is the main contact?
Dr Chris Seal
chris.seal@ncl.ac.uk
Trial website
Contact information
Type
Scientific
Primary contact
Dr Chris Seal
ORCID ID
Contact details
School of Agriculture
Food & Rural Development
Agriculture Building
University of Newcastle upon Tyne
Newcastle upon Tyne
NE1 7RU
United Kingdom
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chris.seal@ncl.ac.uk
Additional identifiers
EudraCT number
ClinicalTrials.gov number
Protocol/serial number
05/Q0905/75
Study information
Scientific title
Randomised controlled trial to test the impact of increased consumption of wholegrain foods on cardiovascular disease (CVD) risk
Acronym
The WHOLEheart study
Study hypothesis
This study will test the hypothesis that increased consumption of wholegrain foods as substitutes for refined grain alternatives in the diet results in reduced CVD risk through improvements in fasting lipid profiles, insulin sensitivity, endothelial function and a reduction in inflammatory status.
Ethics approval
Not provided at time of registration
Study design
Randomised controlled trial
Primary study design
Interventional
Secondary study design
Randomised controlled trial
Trial setting
Not specified
Trial type
Prevention
Patient information sheet
Not available in web format, please use the contact details below to request a patient information sheet
Condition
N/A - this study looks at pre-disease/condition state
Intervention
Treatment A: Control, no intervention
Treatment B: Consuming three portions of wholegrain food per day for four months
Treatment C: Consuming three portions of wholegrain food per day for two months increasing to six portions per day for a further two months
Intervention type
Behavioural
Phase
Drug names
Primary outcome measure
Low-density lipoprotein (LDL) cholesterol
Secondary outcome measures
1. Body Composition:
a. Body weight: in addition to the three main time-points weight will also be measured on volunteers collection of foods (i.e. four weekly intervals)
b. Height
c. Waist circumference
d. Body composition by bio-impedance
2. Fasting Lipid Profile:
a. Duplicate measures of total (high-density lipoprotein [HDL] and LDL cholesterol) triglycerides and non-esterified fatty acids. Distribution of lipoprotein sub-classes by nuclear magnetic resonance (NMR) (to be analysed by Dr Thies, University of Aberdeeen)
3. Insulin Sensitivity (HOMA, modified QUICKI):
a. Duplicate fasting measures of glucose and insulin
b. NEFA concentrations obtained during measurement of fasting lipid profile
4. Inflammatory Status and markers of endothelial function:
a. Serum markers of the acute protein phase response, including sialic acid and C-reactive protein (CRP), fibrinogen and PAI-1
b. The plasma cytokine interleukin-6 (IL-6) as the principal stimulus for the production of acute phase proteins 31, 32
c. Plasma ICAM-1, VCAM-1 and e-selectin as markers of endothelial function
5. Blood pressure:
a. Systolic and diastolic, at rest
6. Dietary change:
a. Dietary change will be assessed using the validated FFQ. Change in intake of other dietary factors which may influence plasma enterolactone concentrations (i.e. fruit and vegetable intake) will be recorded to assess the impact of the dietary intervention on intake of other food groups. Any changes will be included as a factor in subsequent statistical analyses.
Overall trial start date
18/07/2005
Overall trial end date
01/04/2007
Reason abandoned (if study stopped)
Eligibility
Participant inclusion criteria
Men and women, aged 30-65 years and with a body mass index (BMI) >25 kg/m^2
Participant type
Patient
Age group
Adult
Gender
Both
Target number of participants
300 (150 at each centre)
Participant exclusion criteria
Volunteers for the study will be excluded if they are:
1. Habitual consumers of wholegrain cereals and wholegrain bread
2. Individuals receiving clinical treatment for Type 2 diabetes, hyperlipidaemia or hypertension
3. Currently prescribed non-steroidal anti-inflammatory drugs (NSAIDS), aspirin, steroids or immunosuppressants
4. Allergic or intolerant to intervention foods
5. Planning to change dietary habits, increase physical activity, change body weight, move away from the study centre-locality or take a lengthy vacation during the time of the study
6. Heavy smokers (>20 cigarettes per day)
7. Individuals with a history of substance abuse or alcoholism
8. Currently planning pregnancy or have had a baby in the past 12 months
9. Individuals who have shown a recent weight change (>2 kg in past 1 month)
Recruitment start date
18/07/2005
Recruitment end date
01/04/2007
Locations
Countries of recruitment
United Kingdom
Trial participating centre
University of Newcastle upon Tyne
Newcastle upon Tyne
NE1 7RU
United Kingdom
Funders
Funder type
Government
Funder name
Food Standards Agency (N02036)
Alternative name(s)
FSA
Funding Body Type
private sector organisation
Funding Body Subtype
other non-profit
Location
United Kingdom
Results and Publications
Publication and dissemination plan
Not provided at time of registration
Intention to publish date
Participant level data
Not provided at time of registration
Basic results (scientific)
Publication list
1. 2010 results in http://www.ncbi.nlm.nih.gov/pubmed/20307353
2. 2012 results in http://www.ncbi.nlm.nih.gov/pubmed/22170369
3. 2013 results in http://www.ncbi.nlm.nih.gov/pubmed/23269817
Publication citations
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Results
Brownlee IA, Moore C, Chatfield M, Richardson DP, Ashby P, Kuznesof SA, Jebb SA, Seal CJ, Markers of cardiovascular risk are not changed by increased whole-grain intake: the WHOLEheart study, a randomised, controlled dietary intervention., Br. J. Nutr., 2010, 104, 1, 125-134, doi: 10.1017/S0007114510000644.
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Results
Ross AB, Bourgeois A, Macharia HN, Kochhar S, Jebb SA, Brownlee IA, Seal CJ, Plasma alkylresorcinols as a biomarker of whole-grain food consumption in a large population: results from the WHOLEheart Intervention Study., Am. J. Clin. Nutr., 2012, 95, 1, 204-211, doi: 10.3945/ajcn.110.008508.
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Results
Lloyd AJ, Beckmann M, Haldar S, Seal C, Brandt K, Draper J, Data-driven strategy for the discovery of potential urinary biomarkers of habitual dietary exposure., Am. J. Clin. Nutr., 2013, 97, 2, 377-389, doi: 10.3945/ajcn.112.048033.