Reducing Free Sugar Intakes: A Role for Sweet Taste

Study Overview
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Brief Summary
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This randomised controlled trial aims to assess the effects of three different types of dietary advice for reducing free sugar intakes, on intakes of free sugar, in a sample of the UK population.

Detailed Description
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The primary objective of this randomised control trial is to assess the effects of three different types of dietary advice, for reducing total energy intakes (TEI) of free sugar. A total of 150 participants (age 18-65years) consuming diets >5% total energy intake from dietary free sugars will be recruited from across the Dorset region. All participants will be asked to reduce their free sugar intake to <5% TEI, and to aid with this, they will be encouraged to reduce their intakes of specific foods identified as high in free sugars. Participants will also be advised to replace these foods with other foods dependent on their taste. Participants will be randomized to replace high sugar foods with: 1) foods that are low in sugars, but high in sweet taste; 2) foods that are low in sugars, but high in other tastes; and 3) foods that are low in taste. The primary outcome will be changes in free sugar consumption from baseline to endpoint at week 12. Secondary outcomes include change in: BMI; dietary profiles; sweetness preference; sweetness liking; food choices; low calorie sweetener intakes and adherence levels at week 12.

Official Title
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Reducing Free Sugar Intakes: A Role for Sweet Taste

Conditions
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Dietary Behaviour

Intervention / Treatment
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* Behavioral: Dietary Advice


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: aged 18-65 years; able to provide consent and complete all study materials; consuming >5% of TEI from free sugars; residing in the South of England, and able to attend Bournemouth University for testing. Exclusion criteria: individuals who are pregnant or breastfeeding; underweight (BMI <18.5); have pre-existing clinical conditions such as diabetes mellitus, eating disorders, Crohn's disease and other illness's leading to participants receiving external nutritional advice and dietary restrictions; have pre-existing medical conditions affecting swallow ability, taste and smell perception; currently following a specific dietary programme (e.g.: Slimming World); current smokers or have smoked within 3 months of the study start date.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Dietary Advice: Sweet Taste<br>Participants will be asked to reduce their free sugar intakes to less than 5% TEI. To aid with this, they will be asked to reduce their intakes of foods and drinks high in free sugars, and replace these with foods low in sugars, that remain high in sweet taste, eg. fruit, low-calorie sweetened foods and drinks. The intervention will be provided to participants in written form, in an opaque sealed envelope. | Behavioral: Dietary Advice<br>* Dietary Advice<br>|
| Active Comparator: Dietary Advice: Taste<br>Participants will be asked to reduce their free sugar intakes to less than 5% TEI. To aid with this, they will be asked to reduce their intakes of foods and drinks high in free sugars, and replace these with foods low in sugars, that remain high in taste, eg. nuts, foods and drinks flavoured with herbs and spices. The intervention will be provided to participants in written form, in an opaque sealed envelope. | Behavioral: Dietary Advice<br>* Dietary Advice<br>|
| Active Comparator: Dietary Advice: No taste<br>Participants will be asked to reduce their free sugar intakes to less than 5% TEI. To aid with this, they will be asked to reduce their intakes of foods and drinks high in free sugars, and replace these with foods low in sugars, that are low in taste, eg. foods and drinks that are plain-flavoured, wholegrains. The intervention will be provided to participants in written form, in an opaque sealed envelope. | Behavioral: Dietary Advice<br>* Dietary Advice<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Free sugar intakes | Percentage energy intake from free sugars, assessed using diet diaries | Baseline to week 12 | 
| Adherence | Adherence to the recommendations provided, assessed using diet diaries and self-reported adherence | Baseline to week 12 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Dietary Intakes | Nutrient composition and taste of dietary intakes, assessed using diet diaries | Baseline to week 12 | 
| Body weight | Body weight, in kg, assessed using researcher measurements | Baseline to week 12 | 
| BMI | BMI, in kg/m2, assessed using researcher measurements | Baseline to week 12 | 
| Waist circumference | Waist circumference, in cm, assessed using researcher measurements | Baseline to week 12 | 
| Body fat percentage | Body fat percentage, assessed using bioimpedence, as conducted by the researcher measurements | Baseline to week 12 | 
| Sweet food preferences | Preferences for various sweet foods/fluids, assessed using a taste test, where participants sample several sweet and non-sweet foods and rate them for pleasantness on a 100mm Visual Analogue Scale. Higher scores signify stronger preferences | Baseline to week 12 | 
| Sweet food perceptions | Perceptions of the strength of sweet taste for various sweet foods/fluids, assessed using a taste test, where participants sample several sweet and non-sweet foods and rate them for strength of taste on a 100mm Visual Analogue Scale. Higher scores signify stronger perceptions | Baseline to week 12 | 
| Sweet food intakes | Selection of sweet foods/fluids at a given meal, assessed where participants can consume freely from a meal composed of sweet and non-sweet foods, and proportion of sweet foods consumed is measured in terms of weight consumed | Baseline to week 12 | 
| Sweet food attitudes | Attitudes towards sugar, sweeteners, and sweet-tasting foods, assessed using a questionnaire, soon to be published. Higher scores denote stronger attitudes. | Baseline to week 12 | 
| Adverse events | Adverse events, assessed by self-report | Baseline to week 12 | 
| Eating-based attitudes | Attitudes towards eating, assessed using the Three Factor Eating Questionnaire (Karlsson J, et al. IJO 2000; 24: 1715-1725) | Baseline to week 12 | 
| Subjective Quality of Life | Quality of Life, measured using the SF-36 questionnaire (Ware et al, 1996), where Quality of Life is assessed out of 100, where a higher score demonstrates better quality of life | Baseline to week 12 | 
| Barriers and facilitators to success | An assessment of barriers and facilitators to success, assessed by self-report questionnaire | Week 12 |