The RepEAT Study: Individual Differences in Postprandial Glucose Responses and the Relation With Diet and Phenotype

Glucose Metabolism Clinical Trial

— RepEAT  

Official title:

The RepEAT Study: Individual Differences in Postprandial Glucose Responses and the Relation With Diet and Phenotype

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT05456815
• Other study ID #: NL80179.091.21
• Status: Completed
• Phase: N/A
• Start date: August 26, 2022
• Est. completion date: December 13, 2022

Study information

• Verified date: July 2023
• Source: Wageningen University
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

Postprandial glucose responses are related to an increased risk of developing cardiometabolic diseases. Existing research recognizes the presence of inter-individual variation in postprandial glucose responses to the same meal or food product. However, the role of diet and phenotype in postprandial glucose responses is unclear.

The primary objective of this study is to determine the variation in postprandial glucose responses to the same meals/food products and how this relates to the variation in postprandial glucose responses over a 9-week fully controlled dietary intervention within and between individuals. Our secondary objectives are to investigate the difference between postprandial glucose responses to original products and postprandial glucose responses to reformulated products, and to examine the relation between postprandial glucose responses and short-term well-being. In addition, we aim to study the relation between variation in postprandial glucose and phenotype, including immune function, cognitive performance, and microbiota composition.

63 apparently healthy men and women with a BMI of 25-40 kg/m2, aged 45-75 years will be included in the study, comprising a characterization period of 3 weeks and a completely controlled dietary intervention of 9 weeks. During these 9 weeks, glucose will be continuously monitored to measure postprandial glucose responses to standard foods/meals.

There are minor risks for the research subjects of this study. Research subjects will invest approximately 85 hours in the study. During the characterization week, subjects will visit the Wageningen University 3 times and Hospital Gelderse Vallei (Ede, The Netherlands) once. During the controlled dietary intervention, subjects will visit the Wageningen University 2-3 times a week.

Description:

Postprandial glucose responses are related to an increased risk of developing cardiometabolic diseases. Existing research recognizes the presence of inter-individual variation in postprandial glucose responses to the same meal or food product. However, the role of diet, i.e. the other consumed food products and meals, and phenotype in postprandial glucose responses is unclear. A repetitive design and a standardized diet are necessary to determine the variation in postprandial glucose responses to a meal or food product irrespective of the diet.

The primary objective of this study is to determine the variation in postprandial glucose responses to the same meals/food products and how this relates to the variation in postprandial glucose responses over a 9-week fully controlled dietary intervention within and between individuals. Our secondary objectives are to investigate the difference between postprandial glucose responses to original products and postprandial glucose responses to reformulated products, and to examine the relation between postprandial glucose responses and short-term well-being. In addition, we aim to study the relation between variation in postprandial glucose and phenotype, including immune function, cognitive performance, and microbiota composition.

The study population consists of 63 apparently healthy men and women with a BMI of 25-40 kg/m2, aged 45-75 years, and who are weight stable (± <3 kg) for at least three months prior to inclusion.

The study comprises a characterization period of three weeks, followed by a fully controlled dietary intervention trial of nine weeks. In the characterization period, the phenotype of participants will be determined by measures on anthropometrics, immune function, oxidative stress, advanced glycation end-products, cognitive performance, microbiota and gut health, amylase, genetics, and circulating metabolites. The dietary intervention consists of three repetitive rounds of three weeks, in which we test food products in a cross-over setting. Participants will consume test products that fall in the same food category, but differ in glycaemic index/carbohydrate content. Part of these products is provided by industrial partners, of which the original products are reformulated to be reduced in glycaemic index/carbohydrate content. During the 9-week dietary intervention all foods are provided, giving us a complete and detailed picture of food and nutrient intake during this period. The standardized diet follows the average consumption pattern of the study population. Throughout the intervention, interstitial glucose concentrations will be measured using continuous glucose monitoring (CGM) and physical activity will be monitored with an accelerometer.

This study is related to a broad general population. There are minor risks for the research subjects of this study. Placing a continuous glucose sensor generally does not cause pain, but could result in the loss of a drop of blood, or slight skin irritation after wearing. Blood sampling will be performed via a cannula or venapunction and the insertion can be a bit painful and may cause a bruise. During the characterization period, in total 215 mL of blood will be collected in a 3-week timespan. In the following 9 weeks 108 mL, and at the end of the intervention 34 mL blood will be collected. Research subjects will invest approximately 85 hours in the study. During the characterization week, subjects will visit the Wageningen University 3 times and Hospital Gelderse Vallei (Ede, The Netherlands) once. During the controlled dietary intervention, subjects will visit the Wageningen University 2-3 times a week.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 63
• Est. completion date: December 13, 2022
• Est. primary completion date: December 13, 2022
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 45 Years to 75 Years

Eligibility

Inclusion Criteria:

• Apparently healthy men and women

• BMI of 25 - 40 kg/m2

• Age 45-75 years

• Weight stable (± <3 kg) for at least two months prior to inclusion

Exclusion Criteria:

• Diagnosed with type 1 or type 2 diabetes

• Diseases or prior surgeries affecting the stomach, liver, or intestines

• Food allergies/intolerances for products used in the study design

• Receiving medication or supplements interfering with glucose metabolism (as judged by our research physician)

• Regular use of medication interfering with immune function (e.g. corticosteroids, immune blockers, as judged by our research physician)

• Donated blood within 2 months prior to the screening

• Anaemia defined as Hb concentrations <8.5 mmol/L for men and <7.5 mmol/L for women

• Veins not suitable for venflon needle

• Allergy/intolerance to medical skin adhesives

• Dietary habits interfering with the study design (e.g. vegetarian, vegan, ketogenic diet)

• Intention to change the intensity of exercise during the study period

• Current smokers

• Alcohol intake =14 alcoholic beverages per week (women) or =21 alcoholic beverages per week (men)

• Being pregnant or lactating

• Use of soft and/or hard drugs

• Unable/unwilling to download a research application on the mobile phone

• Participation in another study that involves an intervention within two months prior to the intervention

• Working at the division of Human Nutrition and Health of Wageningen University and Research or the Food, Health and Consumer research group of Wageningen University and Biobased Research

Related Conditions & MeSH terms

• Glucose Metabolism

Intervention

Other:
• Standardized diet
During 9 weeks all food products will be standardized and provided by the Research Unit. The standardized diet is based on the average food composition in the Netherlands.

Locations

Country	Name	City	State
Netherlands	Wageningen University, Division of Human Nutrition	Wageningen	Gelderland

Sponsors (1)

Lead Sponsor	Collaborator
Wageningen University

Country where clinical trial is conducted

Netherlands, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Other	Waist-to-hip ratio	Waist-to-hip ratio	Baseline
Other	Body mass index	Body mass index	Baseline
Primary	Blood glucose profile	Interstitial glucose concentrations, as measured by continuous glucose monitoring	Continuous for 9 weeks
Secondary	Short-term well-being	Short-term well-being upon investigational product consumption assessed by the Multidimensional Mood Questionnaire (MDMQ)	Baseline
Secondary	Short-term well-being	Short-term well-being upon investigational product consumption assessed by the Multidimensional Mood Questionnaire (MDMQ)	1 hour post-ingestion
Secondary	Short-term well-being	Short-term well-being upon investigational product consumption assessed by the Multidimensional Mood Questionnaire (MDMQ)	2 hours post-ingestion
Secondary	Short-term well-being	Short-term well-being upon investigational product consumption assessed by the Multidimensional Mood Questionnaire (MDMQ)	4 hours post-ingestion
Secondary	Postprandial glucose blood levels	Postprandial glucose responses in blood upon a mixed meal challenge	Baseline
Secondary	Postprandial glucose blood levels	Postprandial glucose responses in blood upon a mixed meal challenge	30 minutes post-ingestion
Secondary	Postprandial glucose blood levels	Postprandial glucose responses in blood upon a mixed meal challenge	60 minutes post-ingestion
Secondary	Postprandial glucose blood levels	Postprandial glucose responses in blood upon a mixed meal challenge	90 minutes post-ingestion
Secondary	Postprandial glucose blood levels	Postprandial glucose responses in blood upon a mixed meal challenge	120 minutes post-ingestion
Secondary	Postprandial glucose blood levels	Postprandial glucose responses in blood upon a mixed meal challenge	180 minutes post-ingestion
Secondary	Postprandial glucose blood levels	Postprandial glucose responses in blood upon a mixed meal challenge	240 minutes post-ingestion
Secondary	Postprandial insulin blood levels	Postprandial insulin responses in blood upon a mixed meal challenge	Baseline
Secondary	Postprandial insulin blood levels	Postprandial insulin responses in blood upon a mixed meal challenge	30 minutes post-ingestion
Secondary	Postprandial insulin blood levels	Postprandial insulin responses in blood upon a mixed meal challenge	60 minutes post-ingestion
Secondary	Postprandial insulin blood levels	Postprandial insulin responses in blood upon a mixed meal challenge	90 minutes post-ingestion
Secondary	Postprandial insulin blood levels	Postprandial insulin responses in blood upon a mixed meal challenge	120 minutes post-ingestion
Secondary	Postprandial insulin blood levels	Postprandial insulin responses in blood upon a mixed meal challenge	180 minutes post-ingestion
Secondary	Postprandial insulin blood levels	Postprandial insulin responses in blood upon a mixed meal challenge	240 minutes post-ingestion
Secondary	Postprandial metabolite blood levels	Postprandial responses in blood upon a mixed meal challenge as measured by metabolomics	Baseline
Secondary	Postprandial metabolite blood levels	Postprandial responses in blood upon a mixed meal challenge as measured by metabolomics	30 minutes post-ingestion
Secondary	Postprandial metabolite blood levels	Postprandial responses in blood upon a mixed meal challenge as measured by metabolomics	60 minutes post-ingestion
Secondary	Postprandial metabolite blood levels	Postprandial responses in blood upon a mixed meal challenge as measured by metabolomics	90 minutes post-ingestion
Secondary	Postprandial metabolite blood levels	Postprandial responses in blood upon a mixed meal challenge as measured by metabolomics	120 minutes post-ingestion
Secondary	Postprandial metabolite blood levels	Postprandial responses in blood upon a mixed meal challenge as measured by metabolomics	180 minutes post-ingestion
Secondary	Postprandial metabolite blood levels	Postprandial responses in blood upon a mixed meal challenge as measured by metabolomics	240 minutes post-ingestion
Secondary	Postprandial lipid profiling	Postprandial lipid profiling in blood upon a mixed meal challenge	Baseline
Secondary	Postprandial lipid profiling	Postprandial lipid profiling in blood upon a mixed meal challenge	30 minutes post-ingestion
Secondary	Postprandial lipid profiling	Postprandial lipid profiling in blood upon a mixed meal challenge	60 minutes post-ingestion
Secondary	Postprandial lipid profiling	Postprandial lipid profiling in blood upon a mixed meal challenge	90 minutes post-ingestion
Secondary	Postprandial lipid profiling	Postprandial lipid profiling in blood upon a mixed meal challenge	120 minutes post-ingestion
Secondary	Postprandial lipid profiling	Postprandial lipid profiling in blood upon a mixed meal challenge	180 minutes post-ingestion
Secondary	Postprandial lipid profiling	Postprandial lipid profiling in blood upon a mixed meal challenge	240 minutes post-ingestion
Secondary	Postprandial fatty acid blood levels	Postprandial fatty acid concentrations in blood upon a mixed meal challenge	Baseline
Secondary	Postprandial fatty acid blood levels	Postprandial fatty acid concentrations in blood upon a mixed meal challenge	30 minutes post-ingestion
Secondary	Postprandial fatty acid blood levels	Postprandial fatty acid concentrations in blood upon a mixed meal challenge	60 minutes post-ingestion
Secondary	Postprandial fatty acid blood levels	Postprandial fatty acid concentrations in blood upon a mixed meal challenge	90 minutes post-ingestion
Secondary	Postprandial fatty acid blood levels	Postprandial fatty acid concentrations in blood upon a mixed meal challenge	120 minutes post-ingestion
Secondary	Postprandial fatty acid blood levels	Postprandial fatty acid concentrations in blood upon a mixed meal challenge	180 minutes post-ingestion
Secondary	Postprandial fatty acid blood levels	Postprandial fatty acid concentrations in blood upon a mixed meal challenge	240 minutes post-ingestion
Secondary	Postprandial gut hormone blood levels	Postprandial gut hormone concentrations in blood upon a mixed meal challenge	Baseline
Secondary	Postprandial gut hormone blood levels	Postprandial gut hormone concentrations in blood upon a mixed meal challenge	30 minutes post-ingestion
Secondary	Postprandial gut hormone blood levels	Postprandial gut hormone concentrations in blood upon a mixed meal challenge	60 minutes post-ingestion
Secondary	Postprandial gut hormone blood levels	Postprandial gut hormone concentrations in blood upon a mixed meal challenge	90 minutes post-ingestion
Secondary	Postprandial gut hormone blood levels	Postprandial gut hormone concentrations in blood upon a mixed meal challenge	120 minutes post-ingestion
Secondary	Postprandial gut hormone blood levels	Postprandial gut hormone concentrations in blood upon a mixed meal challenge	180 minutes post-ingestion
Secondary	Postprandial gut hormone blood levels	Postprandial gut hormone concentrations in blood upon a mixed meal challenge	240 minutes post-ingestion
Secondary	Cholesterol concentration	Fasting plasma cholesterol concentration	Baseline
Secondary	Postprandial blood glucose levels	Postprandial glucose responses in blood upon an oral glucose tolerance test	Baseline
Secondary	Postprandial blood glucose levels	Postprandial glucose responses in blood upon an oral glucose tolerance test	15 minutes post-ingestion
Secondary	Postprandial blood glucose levels	Postprandial glucose responses in blood upon an oral glucose tolerance test	30 minutes post-ingestion
Secondary	Postprandial blood glucose levels	Postprandial glucose responses in blood upon an oral glucose tolerance test	45 minutes post-ingestion
Secondary	Postprandial blood glucose levels	Postprandial glucose responses in blood upon an oral glucose tolerance test	60 minutes post-ingestion
Secondary	Postprandial blood glucose levels	Postprandial glucose responses in blood upon an oral glucose tolerance test	90 minutes post-ingestion
Secondary	Postprandial blood glucose levels	Postprandial glucose responses in blood upon an oral glucose tolerance test	120 minutes post-ingestion
Secondary	Postprandial blood insulin levels	Postprandial insulin responses in blood upon an oral glucose tolerance test	Baseline
Secondary	Postprandial blood insulin levels	Postprandial insulin responses in blood upon an oral glucose tolerance test	15 minutes post-ingestion
Secondary	Postprandial blood insulin levels	Postprandial insulin responses in blood upon an oral glucose tolerance test	30 minutes post-ingestion
Secondary	Postprandial blood insulin levels	Postprandial insulin responses in blood upon an oral glucose tolerance test	45 minutes post-ingestion
Secondary	Postprandial blood insulin levels	Postprandial insulin responses in blood upon an oral glucose tolerance test	60 minutes post-ingestion
Secondary	Postprandial blood insulin levels	Postprandial insulin responses in blood upon an oral glucose tolerance test	90 minutes post-ingestion
Secondary	Postprandial blood insulin levels	Postprandial insulin responses in blood upon an oral glucose tolerance test	120 minutes post-ingestion
Secondary	Physical activity	Continuous physical activity levels, measured by the Actigraph accelerometer wGT3X-BT (ActiGraph, Pensacola, USA)	Continuous for 9 weeks
Secondary	Physical activity	Continuous physical activity levels, measured by ActivPAL3 micro (PAL Technologies, Glasgow, Scotland) during 3 non-consecutive weeks	Continuous for 3 non-consecutive weeks between week 1 and week 9 of the dietary intervention
Secondary	Body fat distribution	Ratio between visceral and subcutaneous adipose tissue as measured by magnetic resonance imaging (MRI)	Baseline
Secondary	Liver fat content	Liver fat content as measured by MRS	Baseline
Secondary	HbA1c	HbA1c	Baseline
Secondary	Fasting glucose concentration	Fasting glucose concentration	Baseline
Secondary	Fasting insulin concentration	Fasting insulin concentration	Baseline
Secondary	Circulating cytokines	Circulating plasma cytokines	Baseline
Secondary	PBMC composition	Immune function as measured by PBMC composition	Baseline
Secondary	PBMC composition	Immune function as measured by PBMC composition	End of intervention (week 12)
Secondary	Metabolism immune cell populations	Metabolism of immune cell populations as measured by SCENITH	Baseline
Secondary	Immune function	Metabolism of immune cell populations as measured by SCENITH	End of intervention (week 12)
Secondary	Immune response	Immune response upon TLR stimulation	Baseline
Secondary	Immune response	Immune response upon TLR stimulation	End of intervention (week 12)
Secondary	PBMC cytokine production	PBMC cytokine production as measured by intracellular staining	Baseline
Secondary	PBMC cytokine production	PBMC cytokine production as measured by intracellular staining	End of intervention (week 12)
Secondary	Oxidative stress marker urine	Oxidative stress as measured by free 8-iso PGF2a in urine	Baseline
Secondary	Oxidative stress marker urine	Oxidative stress as measured by free 8-iso PGF2a in urine	End of intervention (week 12)
Secondary	Oxidative stress in plasma	Oxidative stress as measured by MDA levels in plasma	Baseline
Secondary	Oxidative stress in plasma	Oxidative stress as measured by MDA levels in plasma	End of intervention (week 12)
Secondary	Oxidative stress in plasma	Oxidative stress as measured by nitrotyrosine in plasma	Baseline
Secondary	Oxidative stress in plasma	Oxidative stress as measured by nitrotyrosine in plasma	End of intervention (week 12)
Secondary	Advanced glycation end-products (AGEs) blood	AGE concentrations in plasma as measured by ultraperformance liquid chromatography-tandem mass spectrometry	Baseline
Secondary	Advanced glycation end-products (AGEs) blood	AGE concentrations in plasma as measured by ultraperformance liquid chromatography-tandem mass spectrometry	End of intervention (week 12)
Secondary	Alpha-dicarbonyl concentrations blood	alpha-dicarbonyl concentrations in plasma as measured by ultraperformance liquid chromatography-tandem mass spectrometry	Baseline
Secondary	Alpha-dicarbonyl concentrations blood	alpha-dicarbonyl concentrations in plasma as measured by ultraperformance liquid chromatography-tandem mass spectrometry	End of intervention (week 12)
Secondary	AGE accumulation	Accumulation of AGEs in the skin as measured by an AGE reader (Diagnoptics, Groningen, the Netherlands)	Baseline
Secondary	AGE accumulation	Accumulation of AGEs in the skin as measured by an AGE reader (Diagnoptics, Groningen, the Netherlands)	End of intervention (week 12)
Secondary	Cognitive performance	Cognitive performance as measured by the Cambridge Neuropsychological Test Automated Battery	Baseline
Secondary	Oral microbiota composition	Microbiota composition in the saliva by extracting bacterial DNA for 16S rRNA sequencing	Baseline
Secondary	Oral microbiota composition	Microbiota composition in the saliva by extracting bacterial DNA for 16S rRNA sequencing	Week 1 dietary intervention
Secondary	Oral microbiota composition	Microbiota composition in the saliva by extracting bacterial DNA for 16S rRNA sequencing	Week 2 dietary intervention
Secondary	Oral microbiota composition	Microbiota composition in the saliva by extracting bacterial DNA for 16S rRNA sequencing	Week 3 dietary intervention
Secondary	Oral microbiota composition	Microbiota composition in the saliva by extracting bacterial DNA for 16S rRNA sequencing	Week 4 dietary intervention
Secondary	Oral microbiota composition	Microbiota composition in the saliva by extracting bacterial DNA for 16S rRNA sequencing	Week 5 dietary intervention
Secondary	Oral microbiota composition	Microbiota composition in the saliva by extracting bacterial DNA for 16S rRNA sequencing	Week 6 dietary intervention
Secondary	Oral microbiota composition	Microbiota composition in the saliva by extracting bacterial DNA for 16S rRNA sequencing	Week 7 dietary intervention
Secondary	Oral microbiota composition	Microbiota composition in the saliva by extracting bacterial DNA for 16S rRNA sequencing	Week 8 dietary intervention
Secondary	Oral microbiota composition	Microbiota composition in the saliva by extracting bacterial DNA for 16S rRNA sequencing	Week 9 dietary intervention
Secondary	Fecal microbiota composition	Microbiota composition in the feces by extracting bacterial DNA for 16S rRNA sequencing	Baseline
Secondary	Fecal microbiota composition	Microbiota composition in the feces by extracting bacterial DNA for 16S rRNA sequencing	Week 1 dietary intervention
Secondary	Fecal microbiota composition	Microbiota composition in the feces by extracting bacterial DNA for 16S rRNA sequencing	Week 2 dietary intervention
Secondary	Fecal microbiota composition	Microbiota composition in the feces by extracting bacterial DNA for 16S rRNA sequencing	Week 3 dietary intervention
Secondary	Fecal microbiota composition	Microbiota composition in the feces by extracting bacterial DNA for 16S rRNA sequencing	Week 4 dietary intervention
Secondary	Fecal microbiota composition	Microbiota composition in the feces by extracting bacterial DNA for 16S rRNA sequencing	Week 5 dietary intervention
Secondary	Fecal microbiota composition	Microbiota composition in the feces by extracting bacterial DNA for 16S rRNA sequencing	Week 6 dietary intervention
Secondary	Fecal microbiota composition	Microbiota composition in the feces by extracting bacterial DNA for 16S rRNA sequencing	Week 7 dietary intervention
Secondary	Fecal microbiota composition	Microbiota composition in the feces by extracting bacterial DNA for 16S rRNA sequencing	Week 8 dietary intervention
Secondary	Fecal microbiota composition	Microbiota composition in the feces by extracting bacterial DNA for 16S rRNA sequencing	Week 9 dietary intervention
Secondary	Self-reported stool consistency	Self-reported stool consistency by using the bristol stool chart (scores between 1-7). Low scores indicate constipation and high scores diarrhea. Scores of 3-4 indicate a 'normal' stool.	Baseline
Secondary	Self-reported stool consistency	Self-reported stool consistency by using the bristol stool chart (scores between 1-7). Low scores indicate constipation and high scores diarrhea. Scores of 3-4 indicate a 'normal' stool.	Week 1 dietary intervention
Secondary	Self-reported stool consistency	Self-reported stool consistency by using the bristol stool chart (scores between 1-7). Low scores indicate constipation and high scores diarrhea. Scores of 3-4 indicate a 'normal' stool.	Week 2 dietary intervention
Secondary	Self-reported stool consistency	Self-reported stool consistency by using the bristol stool chart (scores between 1-7). Low scores indicate constipation and high scores diarrhea. Scores of 3-4 indicate a 'normal' stool.	Week 3 dietary intervention
Secondary	Self-reported stool consistency	Self-reported stool consistency by using the bristol stool chart (scores between 1-7). Low scores indicate constipation and high scores diarrhea. Scores of 3-4 indicate a 'normal' stool.	Week 4 dietary intervention
Secondary	Self-reported stool consistency	Self-reported stool consistency by using the bristol stool chart (scores between 1-7). Low scores indicate constipation and high scores diarrhea. Scores of 3-4 indicate a 'normal' stool.	Week 5 dietary intervention
Secondary	Self-reported stool consistency	Self-reported stool consistency by using the bristol stool chart (scores between 1-7). Low scores indicate constipation and high scores diarrhea. Scores of 3-4 indicate a 'normal' stool.	Week 6 dietary intervention
Secondary	Self-reported stool consistency	Self-reported stool consistency by using the bristol stool chart (scores between 1-7). Low scores indicate constipation and high scores diarrhea. Scores of 3-4 indicate a 'normal' stool.	Week 7 dietary intervention
Secondary	Self-reported stool consistency	Self-reported stool consistency by using the bristol stool chart (scores between 1-7). Low scores indicate constipation and high scores diarrhea. Scores of 3-4 indicate a 'normal' stool.	Week 8 dietary intervention
Secondary	Self-reported stool consistency	Self-reported stool consistency by using the bristol stool chart (scores between 1-7). Low scores indicate constipation and high scores diarrhea. Scores of 3-4 indicate a 'normal' stool.	Week 9 dietary intervention
Secondary	Transit time	Transit time, measured as the time in with blue (dietary) dye is consumed and observed in the feces	Baseline
Secondary	Transit time	Transit time, measured as the time in with blue (dietary) dye is consumed and observed in the feces	End of intervention (week 12)
Secondary	Salivary amylase concentration	Concentration of salivary amylase	Baseline
Secondary	Salivary amylase concentration	Concentration of salivary amylase	End of intervention (week 12)
Secondary	Salivary amylase activity	Activity of salivary amylase	Baseline
Secondary	Salivary amylase activity	Activity of salivary amylase	End of intervention (week 12)
Secondary	Genetic variation amylase genes	SNPs in genes coding for amylase, collected using a mouth swab	Baseline
Secondary	Genetic variation metabolism and responses to food	SNPs in genes relevant for metabolism and responses to food, collected using a mouth swab	Baseline
Secondary	Habitual dietary intake	Habitual dietary intake assessment with a food frequency questionnaire (FFQ)	Baseline
Secondary	Plasma glucose response fries A	Plasma glucose response to fries type A	Baseline
Secondary	Plasma glucose response fries A	Plasma glucose response to fries type A	2 hours post-ingestion
Secondary	Plasma glucose response fries B	Plasma glucose response to fries type B	Baseline
Secondary	Plasma glucose response fries B	Plasma glucose response to fries type B	2 hours post-ingestion
Secondary	Plasma glucose response fries C	Plasma glucose response to fries type C	Baseline
Secondary	Plasma glucose response fries C	Plasma glucose response to fries type C	2 hours post-ingestion
Secondary	Plasma glucose response yoghurt A	Plasma glucose response to yoghurt type A	Baseline
Secondary	Plasma glucose response yoghurt A	Plasma glucose response to yoghurt type A	2 hours post-ingestion
Secondary	Plasma glucose response yoghurt B	Plasma glucose response to yoghurt type B	Baseline
Secondary	Plasma glucose response yoghurt B	Plasma glucose response to yoghurt type B	2 hours post-ingestion
Secondary	Plasma glucose response yoghurt C	Plasma glucose response to yoghurt type C	Baseline
Secondary	Plasma glucose response yoghurt C	Plasma glucose response to yoghurt type C	2 hours post-ingestion
Secondary	Plasma glucose response cake A	Plasma glucose response to cake type A	Baseline
Secondary	Plasma glucose response cake A	Plasma glucose response to cake type A	2 hours post-ingestion
Secondary	Plasma glucose response cake B	Plasma glucose response to cake type B	Baseline
Secondary	Plasma glucose response cake B	Plasma glucose response to cake type B	2 hours post-ingestion
Secondary	Plasma glucose response cake C	Plasma glucose response to cake type C	Baseline
Secondary	Plasma glucose response cake C	Plasma glucose response to cake type C	2 hours post-ingestion
Secondary	Plasma insulin response fries A	Plasma insulin response to fries type A	Baseline
Secondary	Plasma insulin response fries A	Plasma insulin response to fries type A	2 hours post-ingestion
Secondary	Plasma insulin response fries B	Plasma insulin response to fries type B	Baseline
Secondary	Plasma insulin response fries B	Plasma insulin response to fries type B	2 hours post-ingestion
Secondary	Plasma insulin response fries C	Plasma insulin response to fries type C	Baseline
Secondary	Plasma insulin response fries C	Plasma insulin response to fries type C	2 hours post-ingestion
Secondary	Plasma insulin response yoghurt A	Plasma insulin response to yoghurt type A	Baseline
Secondary	Plasma insulin response yoghurt A	Plasma insulin response to yoghurt type A	2 hours post-ingestion
Secondary	Plasma insulin response yoghurt B	Plasma insulin response to yoghurt type B	Baseline
Secondary	Plasma insulin response yoghurt B	Plasma insulin response to yoghurt type B	2 hours post-ingestion
Secondary	Plasma insulin response yoghurt C	Plasma insulin response to yoghurt type C	Baseline
Secondary	Plasma insulin response yoghurt C	Plasma insulin response to yoghurt type C	2 hours post-ingestion
Secondary	Plasma insulin response cake A	Plasma insulin response to cake type A	Baseline
Secondary	Plasma insulin response cake A	Plasma insulin response to cake type A	2 hours post-ingestion
Secondary	Plasma insulin response cake B	Plasma insulin response to cake type B	Baseline
Secondary	Plasma insulin response cake B	Plasma insulin response to cake type B	2 hours post-ingestion
Secondary	Plasma insulin response cake C	Plasma insulin response to cake type C	Baseline
Secondary	Plasma insulin response cake C	Plasma insulin response to cake type C	2 hours post-ingestion