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Trial record 3 of 13 for:    "Dietary Carbohydrates" | Recruiting, Not yet recruiting, Available Studies

Dietary Carbohydrate Manipulation and Energy Balance: RCT

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ClinicalTrials.gov Identifier: NCT03574987
Recruitment Status : Not yet recruiting
First Posted : July 2, 2018
Last Update Posted : July 2, 2018
Sponsor:
Information provided by (Responsible Party):
Javier Gonzalez, University of Bath

Brief Summary:
This study will investigate how dietary sugar and carbohydrates influence metabolism and health across a 12-week period, with a focus on physical activity. One third of participants will eat a diet with typical amounts of sugar and carbohydrate, one third of participants will eat a diet with sugar intake restricted, and the final third of participants will eat a diet where both sugar and total carbohydrates are restricted and replaced with fat.

Condition or disease Intervention/treatment Phase
Physical Activity Diet Modification Other: Diet Not Applicable

Detailed Description:

Sugar is perceived negatively, leading to government taxation and targets to reduce consumption. These actions have been taken based on the limited evidence that high-sugar diets are associated with greater total energy intake. However, energy intake is only one half of the energy balance equation (energy in vs energy out). Without considering energy expenditure, it is impossible to fully understand the effects of sugar on health. Removing dietary sugar or carbohydrates from the diet may influence energy balance through mechanisms other than energy intake - for example by reducing levels of physical activity.

Understanding dietary regulators of energy balance is more important than ever because diseases like obesity are a consequence of energy surplus (i.e. energy in > energy out). No studies have investigated a causal role of dietary sugar or carbohydrate on energy balance. The proposed research will seek to understand the responses to manipulating dietary carbohydrate and sugar content on energy balance and health. This research will enable the public to make informed dietary choices about carbohydrate and sugar consumption.

To achieve this, healthy non-obese adults, aged 18-65 years will be recruited to take part in an intervention study with measures of energy intake, energy expenditure, metabolic health, gut microbiota, and appetite. All laboratory trials will take place at the University of Bath. Participants will be randomised to consume one of three diets for a period of 12 weeks, with laboratory visits at baseline, at week 4, and at week 12:

  1. CONTROL (moderate sugar) - reflecting the composition of a typical European diet
  2. Low sugar - the same composition of a typical European diet but with <5% energy intake from sugar
  3. Low carbohydrate - low carbohydrate diet with <5% energy intake from sugar, replacing carbohydrate energy with fat

Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 60 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Intervention Model Description: Randomised controlled trial with 3 arms. One arm is a typical diet (50% CHO, 20% SUG), one arm is low sugar (50% CHO, <5% SUG), one arm is low carbohydrate (<8% CHO, <5% SUG). Stratified by sex and physical activity level (PAL).
Masking: None (Open Label)
Primary Purpose: Basic Science
Official Title: The Effect of Dietary Carbohydrate Manipulation on All Major Aspects of Energy Balance: A 12-week Randomised Controlled Trial
Estimated Study Start Date : September 1, 2018
Estimated Primary Completion Date : September 1, 2021
Estimated Study Completion Date : September 1, 2021

Resource links provided by the National Library of Medicine


Arm Intervention/treatment
Active Comparator: CONTROL
Diet consisting of 50% carbohydrate (20% sugar), 15% protein, 35% fat
Other: Diet
Macronutrient composition (specifically type and/or amount of carbohydrate) is manipulated

Experimental: LOW SUG
Diet consisting of 50% carbohydrate (<5% sugar), 15% protein, 35% fat
Other: Diet
Macronutrient composition (specifically type and/or amount of carbohydrate) is manipulated

Experimental: LOW CHO
Diet consisting of <8% carbohydrate (<5% sugar), 15% protein, >77% fat
Other: Diet
Macronutrient composition (specifically type and/or amount of carbohydrate) is manipulated




Primary Outcome Measures :
  1. Physical activity energy expenditure (kJ/day) [ Time Frame: 7 days (across 12 weeks) ]
    24-hour physical activity energy expenditure (kJ/day)


Secondary Outcome Measures :
  1. Fasting metabolite/hormone profile [ Time Frame: 12 weeks ]
    Assessment of blood glucose, insulin, triglycerides, non-esterified fatty acids, lactate, beta-hydroxybutyrate, leptin, fibroblast growth factor-21, high density lipoprotein, and low density lipoprotein concentrations

  2. Postprandial metabolite/hormone profile [ Time Frame: 4 hours (across 12 weeks) ]
    Assessment of blood glucose, insulin, triglycerides, non-esterified fatty acids, lactate, beta-hydroxybutyrate, leptin, fibroblast growth factor-21, high density lipoprotein, and low density lipoprotein concentrations

  3. Food preference ratings [ Time Frame: 12 weeks ]
    Food preference ratings determined by bespoke computer software

  4. Subjective appetite [ Time Frame: 12 weeks ]
    Measured by 0-100 mm visual analogue scale

  5. Step count [ Time Frame: 12 weeks ]
    Measured daily using pedometers

  6. Weight [ Time Frame: 12 weeks ]
    Measured weekly using electric scales

  7. Body composition [ Time Frame: 12 weeks ]
    Measured using dual x-ray absorptiometry

  8. Bone mineral density [ Time Frame: 12 weeks ]
    Measured using peripheral quantitative computed tomography

  9. Blood pressure [ Time Frame: 12 weeks ]
    Measured using an automated sphygmomanometer

  10. Interstitial glucose concentrations [ Time Frame: 7 days (across 12 weeks) ]
    Measured using freestyle libre glucose monitors

  11. Protein glycation [ Time Frame: 12 weeks ]
    Various proteins in blood samples

  12. Adipose tissue gene expression [ Time Frame: 12 weeks ]
    Expression of a panel of genes related to glucose metabolism in adipose biopsies using real-time polymerase chain reaction

  13. Muscle tissue gene expression [ Time Frame: 12 weeks ]
    Expression of a panel of genes related to glucose metabolism in muscle biopsies using real-time polymerase chain reaction

  14. Adipose tissue protein expression [ Time Frame: 12 weeks ]
    Expression of various proteins related to glucose metabolism in adipose biopsies via Western blot

  15. Muscle tissue protein expression [ Time Frame: 12 weeks ]
    Expression of various proteins related to glucose metabolism in muscle biopsies via Western blot

  16. Gut microbiome characterisation [ Time Frame: 12 weeks ]
    Faecal sample DNA and water will be used to determine taxonomic and functional diversity of microbes

  17. Faecal energy density [ Time Frame: 12 weeks ]
    Faecal sample energy density will be measured using bomb calorimetry

  18. Urinary beta-hydroxybutyrate concentrations [ Time Frame: 12 weeks ]
    Will be measured using handheld sticks

  19. Urine urea nitrogen excretion [ Time Frame: 12 weeks ]
    Will be measured across trial days

  20. Energy intake [ Time Frame: 12 weeks ]
    Estimated using food diaries

  21. Genetic variation [ Time Frame: 12 weeks ]
    SNPs related to glucose metabolism will be measured from the buffy coat layer of blood samples



Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 65 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Body mass index 18.5-29.9 kg∙m-2
  • Age 18-65 years
  • Able and willing to provide informed consent and safely comply with study procedures
  • Females to maintain record of regular menstrual cycle phase/contraceptive use
  • No anticipated changes in physical activity during the first 4 weeks of the study (e.g. holidays or training programmes)

Exclusion Criteria:

  • Any reported condition or behaviour deemed either to pose undue personal risk to the participant or introduce bias
  • Any diagnosed metabolic disease (e.g. type 1 or type 2 diabetes)
  • Any reported use of substances which may pose undue personal risk to the participants or introduce bias into the experiment
  • Lifestyle not conforming to standard sleep-wake cycle (e.g. shift worker)
  • Any reported recent (<6 months) change in body mass (± 3%)
  • Use of antibiotic medication in the last 3 months
  • Use of prebiotic or probiotic products in the last month

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03574987


Locations
United Kingdom
Department for Health, University of Bath Not yet recruiting
Bath, United Kingdom, BA2 7AY
Contact: Aaron Hengist, BSc    +44 (0) 1225 385434    A.Hengist@bath.ac.uk   
Contact: Javier T Gonzalez, PhD    +44 (0) 1225 385518    J.T.Gonzalez@bath.ac.uk   
Sub-Investigator: Russell Davies, BSc         
Sub-Investigator: Francoise Koumanov, PhD         
Sub-Investigator: Dylan Thompson, PhD         
Sub-Investigator: James A Betts, PhD         
Sponsors and Collaborators
University of Bath