<clinical_study>
  <!-- This xml conforms to an XML Schema at:
    https://clinicaltrials.gov/ct2/html/images/info/public.xsd -->
  <required_header>
    <download_date>ClinicalTrials.gov processed this data on September 20, 2023</download_date>
    <link_text>Link to the current ClinicalTrials.gov record.</link_text>
    <url>https://clinicaltrials.gov/ct2/show/NCT04497974</url>
  </required_header>
  <id_info>
    <org_study_id>NL72134.081.19</org_study_id>
    <nct_id>NCT04497974</nct_id>
  </id_info>
  <brief_title>Sweet Tooth: Nature or Nurture? Role of Long-term Dietary Sweetness Exposure on Sweetness Preferences</brief_title>
  <official_title>Role of Long-term Dietary Sweetness Exposure on Sweetness Preferences</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>Wageningen University</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
    <collaborator>
      <agency>Bournemouth University</agency>
      <agency_class>Other</agency_class>
    </collaborator>
    <collaborator>
      <agency>TKI Agri &amp; Food</agency>
      <agency_class>Other</agency_class>
    </collaborator>
    <collaborator>
      <agency>Top Institute Food and Nutrition</agency>
      <agency_class>Other</agency_class>
    </collaborator>
    <collaborator>
      <agency>American Beverage Association</agency>
      <agency_class>Other</agency_class>
    </collaborator>
    <collaborator>
      <agency>Arla Foods</agency>
      <agency_class>Industry</agency_class>
    </collaborator>
    <collaborator>
      <agency>Cargill</agency>
      <agency_class>Industry</agency_class>
    </collaborator>
    <collaborator>
      <agency>Firmenich, Switzerland</agency>
      <agency_class>Other</agency_class>
    </collaborator>
    <collaborator>
      <agency>International Sweeteners Association</agency>
      <agency_class>Other</agency_class>
    </collaborator>
    <collaborator>
      <agency>SinoSweet, China</agency>
      <agency_class>Other</agency_class>
    </collaborator>
    <collaborator>
      <agency>Stichting Kenniscentrum Suiker &amp; Voeding, Netherlands</agency>
      <agency_class>Other</agency_class>
    </collaborator>
    <collaborator>
      <agency>Unilever R&amp;D</agency>
      <agency_class>Industry</agency_class>
    </collaborator>
  </sponsors>
  <source>Wageningen University</source>
  <oversight_info>
    <is_fda_regulated_drug>No</is_fda_regulated_drug>
    <is_fda_regulated_device>No</is_fda_regulated_device>
  </oversight_info>
  <brief_summary>
    <textblock>
      In recent years, social pressure has been exerted towards lowering sugar and sweetness levels&#xD;
      in foods, with the aim of decreasing the sweetness preference of the general population.&#xD;
      However, the resilience/flexibility of sweetness preferences and the impact on energy intake&#xD;
      is a fundamental knowledge gap. Recent, relatively long-term studies limited to no more than&#xD;
      3 months did not find a relationship between sweetness exposure and sweetness preferences.&#xD;
      Therefore, a longer-term systematic investigation is necessary to objectively evaluate&#xD;
      whether sweetness preferences can be altered via varying the sweetness exposure and whether&#xD;
      it can affect other outcomes, such as perceived taste intensity, food intake, body weight,&#xD;
      body composition, glucose homeostasis and sweet liker type. The study sample will consist of&#xD;
      180 subjects. Enrolled participants will be distributed into three intervention groups;&#xD;
      regular dietary sweetness exposure (n=60); low dietary sweetness exposure (n=60); and high&#xD;
      dietary sweetness exposure (n =60). The intervention is semi-controlled for a period of six&#xD;
      months. Preference and perceived taste intensity of a series of familiar and unfamiliar foods&#xD;
      will be assessed at baseline (Day 0), during the intervention (Month 1, Month 3, Month 6) and&#xD;
      in the follow-up period (Month 7, Month 10). Furthermore, outcomes such as observed food&#xD;
      choice and intake during a test meal, reported food preferences, reported food cravings,&#xD;
      sweet-liker type, glucose homeostasis, body weight, body composition and biomarkers related&#xD;
      to diabetes and cardiovascular disease will be assessed as well.&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      Evidence supporting sweetness preference alterations via variations in dietary sweetness&#xD;
      exposure is limited. Most studies investigating this focused only on specific sweet elements&#xD;
      in the diet, (e.g. beverages; mono- and disaccharides; high-energy dense snacks) instead of&#xD;
      sweetness in the diet as a whole. Furthermore, there is no clear evidence about the relation&#xD;
      between dietary sweetness exposure and weight gain. Therefore, longer term,&#xD;
      sufficiently-powered studies with a 'whole diet' approach are needed to address the question&#xD;
      whether sweet preferences can be altered (suppressed or stimulated) by variations in&#xD;
      sweetness exposure. It is important to answer this question so that dietary recommendations&#xD;
      can be scientifically tailored accordingly. The present study will provide breakthrough&#xD;
      evidence about the flexibility/adaptability of sweetness preferences, in terms of effect&#xD;
      sizes and direction, duration of effects, and impact on dietary intake, glucose homeostasis&#xD;
      and body weight. This information is particularly relevant for product development by food&#xD;
      industries in the context of reformulation strategies, and for governments to base their&#xD;
      dietary guidelines upon.&#xD;
&#xD;
      The primary study objective is to assess the effect of a 6-month low, regular and high&#xD;
      dietary sweetness exposure on sweetness preference in a series of familiar and unfamiliar&#xD;
      foods. Preference will be assessed in both familiar and unfamiliar foods since, preferences&#xD;
      in familiar, commonly eaten foods might by harder to change compared to those for unfamiliar&#xD;
      foods, because there is no consumer-expected sweetness level associated with unfamiliar&#xD;
      foods. The secondary objective is to assess the effect of a 6-month low, regular and high&#xD;
      dietary sweetness exposure on sweetness perception, food choice and intake during a test&#xD;
      meal, dietary taste patterns, taste preferences, food cravings, sweet-liker type, glucose&#xD;
      homeostasis, biomarkers related to cardiovascular disease (CVD) and diabetes, body weight and&#xD;
      body composition. Participants will be matched on age, gender, BMI and sweet liker status and&#xD;
      randomly allocated to one of the three intervention arms: (1) regular dietary sweetness&#xD;
      exposure (25-30 percent daily energy from sweet foods) (control) (n=60); (2) low dietary&#xD;
      sweetness exposure (10-15 percent daily energy from sweet foods) (n=60); and (3) high dietary&#xD;
      sweetness exposure (40-45 percent daily energy from sweet foods) (n=60). The intervention is&#xD;
      semi-controlled, meaning that 50 percent of the foods will be provided to participants. Foods&#xD;
      are offered ad libitum, on a weekly basis and macronutrient composition of the offered foods&#xD;
      is similar in energy and macronutrient composition, that is fat, protein, carbohydrates and&#xD;
      fibres, but different in sweetness. New methodology of our group enables us to assess&#xD;
      sweetness exposure within a diet, by profiling foods based on six taste clusters (neutral;&#xD;
      salt, umami &amp; fat; sweet and fat; sweet and sour; fat; bitter).&#xD;
&#xD;
      Preference and perceived taste intensity will be assessed during hedonic and sensory&#xD;
      evaluation of eight foods; three sweet familiar, three sweet unfamiliar and two salty&#xD;
      familiar ones. Foods are solid, semi-solid and liquid. Furthermore, observed food choice and&#xD;
      intake during test meals, reported food preferences, reported food cravings, sweet-liker&#xD;
      type, glucose homeostasis, body weight, body composition and biomarkers related to diabetes&#xD;
      and cardiovascular disease will be assessed. Outcomes will be assessed several times; at&#xD;
      baseline (Month 0), during the intervention Month 1, Month 3, Month 6 and in the follow up&#xD;
      period (Month 7, Month 10). Compliance will be assessed with 24-hour urine sample and dietary&#xD;
      assessment methods (24-hour recalls).&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Recruiting</overall_status>
  <start_date type="Actual">October 20, 2020</start_date>
  <completion_date type="Anticipated">August 2024</completion_date>
  <primary_completion_date type="Anticipated">August 2024</primary_completion_date>
  <phase>N/A</phase>
  <study_type>Interventional</study_type>
  <has_expanded_access>No</has_expanded_access>
  <study_design_info>
    <allocation>Randomized</allocation>
    <intervention_model>Parallel Assignment</intervention_model>
    <intervention_model_description>Randomised controlled intervention study</intervention_model_description>
    <primary_purpose>Basic Science</primary_purpose>
    <masking>Double (Participant, Investigator)</masking>
  </study_design_info>
  <primary_outcome>
    <measure>Change in preference score.</measure>
    <time_frame>from month 0 to month 6.</time_frame>
    <description>Measured during preference testing, using Ranking on a scale methodology (scale anchored at 0: Dislike extremely; 50: Neither dislike or like; 100: Like extremely) in a series of test foods.</description>
  </primary_outcome>
  <secondary_outcome>
    <measure>Change in preference score.</measure>
    <time_frame>from month 0 to month 1, 3, 7 ad 10.</time_frame>
    <description>Measured during preference testing, using Ranking on a scale methodology (scale anchored at 0: Dislike extremely; 50: Neither dislike or like; 100: Like extremely) in a series of test foods.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Difference in mean liking scores between familiar and unfamiliar foods.</measure>
    <time_frame>Measured at 0, 1, 3, 6, 7 and 10 months.</time_frame>
    <description>Measured during preference testing, using Ranking on a scale methodology (scale anchored at 0: Dislike extremely; 50: Neither dislike or like; 100: Like extremely) in a series of test foods.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Change in sensory intensity scores.</measure>
    <time_frame>Measured at 0, 1, 3, 6, 7 and 10 months.</time_frame>
    <description>Measured during sensory testing, using 100-unit Visual analogue scale (VAS), (anchored at 0: not sweet/salty at all; 100: Extremely sweet/salty) in a series of test foods.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Change in energy intake.</measure>
    <time_frame>Measured at 0, 1, 3, 6, 7 and 10 months.</time_frame>
    <description>Measured during ad-libitum test meal in kcal.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Change in energy intake.</measure>
    <time_frame>Measured at 0, 1, 3, 6, 7 and 10 months.</time_frame>
    <description>Measured during ad-libitum test meal in kJ.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Proportion of eaten sweet foods vs. foods from other taste modalities.</measure>
    <time_frame>Measured at 0, 1, 3, 6, 7 and 10 months</time_frame>
    <description>Measured during ad-libitum test meal in proportions.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Sweet-liker status score.</measure>
    <time_frame>Measured at 0, 1, 3, 6, 7 and 10 months.</time_frame>
    <description>Measured on a 100-unit VAS scale (anchored at 0: Dislike; 100: Like).</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Food craving questionnaire scores.</measure>
    <time_frame>Measured at 0, 1, 3, 6, 7 and 10 months.</time_frame>
    <description>Measured using the Control of eating questionnaire (CoEQ)</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Taste preference questionnaire scores.</measure>
    <time_frame>Measured at 0, 1, 3, 6, 7 and 10 months.</time_frame>
    <description>Measured using Taste Preference questionnaire (PrefQuest).</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Dietary taste patterns.</measure>
    <time_frame>Measured at 0, 1, 3, 6, 7 and 10 months.</time_frame>
    <description>Measured with the Taste food frequency questionnaire in frequency.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Dietary taste patterns.</measure>
    <time_frame>Measured at 0, 1, 3, 6, 7 and 10 months.</time_frame>
    <description>Measured with the Taste food frequency questionnaire in % of energy coming from each taste cluster.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Dietary taste patterns.</measure>
    <time_frame>Measured at 0, 1, 3, 6, 7 and 10 months.</time_frame>
    <description>Measured with the Taste food frequency questionnaire in % of food weight coming from each taste cluster.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Body weight.</measure>
    <time_frame>Measured at 0, 1, 2, 3, 4, 5, 6, 7 and 10 months.</time_frame>
    <description>Measured with a weighing scale in kg.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Waist-to-hip ratio.</measure>
    <time_frame>Measured at 0, 1, 3, 6, 7 and 10 months.</time_frame>
    <description>Measured using a stretch-resistant tape.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>% of body fat mass and lean body mass (fat free mass).</measure>
    <time_frame>Measured at 0, 6 and 10 months.</time_frame>
    <description>Measured with a dual energy x-ray absorptiometry (DEXA).</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Variation in interstitial glucose levels.</measure>
    <time_frame>Measured at 0, 6 and 10 months.</time_frame>
    <description>Measured with glucose monitoring sensor (only measured in a subgroup, of 60 subjects, 20 per intervention arm).</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Change in fasting glucose, insulin, total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides levels in blood.</measure>
    <time_frame>Measured at 0, 1, 3, 6, 7 and 10 months.</time_frame>
    <description>Measured in blood in mmol/L.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Adverse events.</measure>
    <time_frame>Measured at 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10 months.</time_frame>
    <description>Self-reported and monitored.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Concentration of biomarkers in urine related to sugar, low and no calorie sweeteners, protein and salt intake.</measure>
    <time_frame>Measured at 0, 1, 3, 6, 7 and 10 months.</time_frame>
    <description>Measured in urine in mg/d.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Intake levels of foods, food groups and macronutrients.</measure>
    <time_frame>Measured at 0, 1, 2, 3, 4, 5, 6, 7 and 10 months.</time_frame>
    <description>Measured with 24-hour recalls, in kcal/day.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Intake levels of foods, food groups and macronutrients.</measure>
    <time_frame>Measured at 0, 1, 2, 3, 4, 5, 6, 7 and 10 months.</time_frame>
    <description>Measured with 24-hour recalls, in kJ/day.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Intake levels of foods, food groups and macronutrients.</measure>
    <time_frame>Measured at 0, 1, 2, 3, 4, 5, 6, 7 and 10 months.</time_frame>
    <description>Measured with 24-hour recalls, in g/day.</description>
  </secondary_outcome>
  <other_outcome>
    <measure>Gender.</measure>
    <time_frame>Assessed at month 0.</time_frame>
    <description>Self-reported.</description>
  </other_outcome>
  <other_outcome>
    <measure>Height.</measure>
    <time_frame>Assessed at month 0.</time_frame>
    <description>Measured with a stadiometer.</description>
  </other_outcome>
  <other_outcome>
    <measure>Physical activity level.</measure>
    <time_frame>Measured at 0, 1, 3, 6, 7 and 10 months.</time_frame>
    <description>Measured with the Short Questionnaire to Assess Health enhancing physical activity (SQUASH).</description>
  </other_outcome>
  <other_outcome>
    <measure>Polymorphisms in the genes related to the sweet taste perception.</measure>
    <time_frame>Assessed at month 0.</time_frame>
    <description>Genes will be extracted from collected blood samples.</description>
  </other_outcome>
  <other_outcome>
    <measure>Age.</measure>
    <time_frame>Assessed at month 0.</time_frame>
    <description>Self-reported.</description>
  </other_outcome>
  <other_outcome>
    <measure>Medicine usage.</measure>
    <time_frame>Assessed at month 0.</time_frame>
    <description>Number and type of medicine used, self-reported.</description>
  </other_outcome>
  <number_of_arms>3</number_of_arms>
  <enrollment type="Anticipated">180</enrollment>
  <condition>Food Preferences</condition>
  <arm_group>
    <arm_group_label>Regular dietary sweetness exposure - Control</arm_group_label>
    <arm_group_type>Active Comparator</arm_group_type>
    <description>Regular dietary sweetness exposure (RSE) - The RSE group consumes a diet with 25 - 30 % energy from sweet tasting foods, for 6 months.</description>
  </arm_group>
  <arm_group>
    <arm_group_label>Low dietary sweetness exposure - Experimental</arm_group_label>
    <arm_group_type>Experimental</arm_group_type>
    <description>Low dietary sweetness exposure (LSE) - The LSE group consumes a diet with 10 - 15 % energy from sweet tasting foods, for 6 months.</description>
  </arm_group>
  <arm_group>
    <arm_group_label>High dietary sweetness exposure - Experimental</arm_group_label>
    <arm_group_type>Experimental</arm_group_type>
    <description>High dietary sweetness exposure (HSE) - The HSE group consumes a diet with 40 - 45 % energy from sweet tasting foods, for 6 months.</description>
  </arm_group>
  <intervention>
    <intervention_type>Other</intervention_type>
    <intervention_name>Dietary intervention</intervention_name>
    <description>Varying the exposure to sweetness via diet manipulation.</description>
    <arm_group_label>High dietary sweetness exposure - Experimental</arm_group_label>
    <arm_group_label>Low dietary sweetness exposure - Experimental</arm_group_label>
    <arm_group_label>Regular dietary sweetness exposure - Control</arm_group_label>
  </intervention>
  <eligibility>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
          -  Good general health;&#xD;
&#xD;
          -  Age 18 - 65 years;&#xD;
&#xD;
          -  Body mass index 18.5 - 30 kg/m2;&#xD;
&#xD;
          -  Having normal taste ability (assessed with taste strips test);&#xD;
&#xD;
          -  Having normal glucose levels in blood (assessed with a finger prick);&#xD;
&#xD;
          -  Able to provide informed consent;&#xD;
&#xD;
          -  Able to attend Wageningen University, as required for testing.&#xD;
&#xD;
        Exclusion Criteria:&#xD;
&#xD;
          -  Diagnosed with diabetes currently or in the past;&#xD;
&#xD;
          -  Has been notified to have insulin resistance currently or in the past;&#xD;
&#xD;
          -  Diagnosed with endocrine diseases or other metabolic diseases that influence&#xD;
             metabolism;&#xD;
&#xD;
          -  Diagnosed with eating disorders;&#xD;
&#xD;
          -  Diagnosed with taste or smell disorder;&#xD;
&#xD;
          -  Pregnant or lactating during the study intervention;&#xD;
&#xD;
          -  Gain or loss of more than 3 kg in the last three months prior to study entry;&#xD;
&#xD;
          -  Suffering from lack of appetite (self-report);&#xD;
&#xD;
          -  Use of medication that may influence study results; such as medication that may affect&#xD;
             blood sugar;&#xD;
&#xD;
          -  Having a food allergy or/and food intolerance for foods used in the preference testing&#xD;
             (e.g. lactose intolerance, celiac disease, egg allergy);&#xD;
&#xD;
          -  Consumes more than 14 glasses of alcohol per week;&#xD;
&#xD;
          -  Use of soft or hard drugs (e.g. cannabis);&#xD;
&#xD;
          -  Student or personnel of Nutrition and Health at Wageningen University;&#xD;
&#xD;
          -  Participating in another study/studies or planning to participate in another study.&#xD;
&#xD;
        Specific criteria for withdrawal:&#xD;
&#xD;
          -  Pregnancy;&#xD;
&#xD;
          -  Weight change of 4 kg or more. In a case of systematic weight change - a subject has&#xD;
             gained or lost 4 kg or more at the 3-month period, he/she will be excluded from the&#xD;
             study (stop criterion).&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>18 Years</minimum_age>
    <maximum_age>65 Years</maximum_age>
    <healthy_volunteers>Accepts Healthy Volunteers</healthy_volunteers>
  </eligibility>
  <overall_official>
    <last_name>Kees de Graaf</last_name>
    <role>Study Chair</role>
    <affiliation>WU</affiliation>
  </overall_official>
  <overall_official>
    <last_name>Monica Mars</last_name>
    <role>Principal Investigator</role>
    <affiliation>WU</affiliation>
  </overall_official>
  <overall_contact>
    <last_name>Eva Marija Cad, MSc</last_name>
    <phone>+31317488077</phone>
    <email>eva.cad@wur.nl</email>
  </overall_contact>
  <location>
    <facility>
      <name>Department of Human Nutrition, Wageningen University</name>
      <address>
        <city>Wageningen</city>
        <country>Netherlands</country>
      </address>
    </facility>
    <status>Recruiting</status>
    <contact>
      <last_name>Eva Cad</last_name>
    </contact>
  </location>
  <location_countries>
    <country>Netherlands</country>
  </location_countries>
  <verification_date>July 2022</verification_date>
  <study_first_submitted>December 16, 2019</study_first_submitted>
  <study_first_submitted_qc>July 30, 2020</study_first_submitted_qc>
  <study_first_posted type="Actual">August 4, 2020</study_first_posted>
  <last_update_submitted>July 19, 2022</last_update_submitted>
  <last_update_submitted_qc>July 19, 2022</last_update_submitted_qc>
  <last_update_posted type="Actual">July 20, 2022</last_update_posted>
  <responsible_party>
    <responsible_party_type>Sponsor</responsible_party_type>
  </responsible_party>
  <keyword>sweetness</keyword>
  <keyword>preferences</keyword>
  <patient_data>
    <sharing_ipd>Yes</sharing_ipd>
    <ipd_description>Individual participant data that underline the results reported in an article after de-identification will be shared.</ipd_description>
    <ipd_info_type>Study Protocol</ipd_info_type>
    <ipd_info_type>Statistical Analysis Plan (SAP)</ipd_info_type>
    <ipd_info_type>Analytic Code</ipd_info_type>
    <ipd_time_frame>Immediately following the publication. No end date.</ipd_time_frame>
    <ipd_access_criteria>Anyone who wishes to access the data. Individuals who wish to use the data for secondary analysis must contact corresponding authors of respective/specific publications for their approval. They must also reference the source of the data to provide appropriate credit to those who generated it and allow searching for the studies it has supported.</ipd_access_criteria>
  </patient_data>
  <!-- Results have not yet been posted for this study                                          -->
</clinical_study>


download date: ClinicalTrials.gov processed this data on September 20, 2023
link text: Link to the current ClinicalTrials.gov record.
url: https://clinicaltrials.gov/ct2/show/NCT04497974
org study id: NL72134.081.19
nct id: NCT04497974
lead sponsor: 
collaborator: 
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is fda regulated drug: No
is fda regulated device: No
In recent years, social pressure has been exerted towards lowering sugar and sweetness levels
      in foods, with the aim of decreasing the sweetness preference of the general population.
      However, the resilience/flexibility of sweetness preferences and the impact on energy intake
      is a fundamental knowledge gap. Recent, relatively long-term studies limited to no more than
      3 months did not find a relationship between sweetness exposure and sweetness preferences.
      Therefore, a longer-term systematic investigation is necessary to objectively evaluate
      whether sweetness preferences can be altered via varying the sweetness exposure and whether
      it can affect other outcomes, such as perceived taste intensity, food intake, body weight,
      body composition, glucose homeostasis and sweet liker type. The study sample will consist of
      180 subjects. Enrolled participants will be distributed into three intervention groups;
      regular dietary sweetness exposure (n=60); low dietary sweetness exposure (n=60); and high
      dietary sweetness exposure (n =60). The intervention is semi-controlled for a period of six
      months. Preference and perceived taste intensity of a series of familiar and unfamiliar foods
      will be assessed at baseline (Day 0), during the intervention (Month 1, Month 3, Month 6) and
      in the follow-up period (Month 7, Month 10). Furthermore, outcomes such as observed food
      choice and intake during a test meal, reported food preferences, reported food cravings,
      sweet-liker type, glucose homeostasis, body weight, body composition and biomarkers related
      to diabetes and cardiovascular disease will be assessed as well.
Evidence supporting sweetness preference alterations via variations in dietary sweetness
      exposure is limited. Most studies investigating this focused only on specific sweet elements
      in the diet, (e.g. beverages; mono- and disaccharides; high-energy dense snacks) instead of
      sweetness in the diet as a whole. Furthermore, there is no clear evidence about the relation
      between dietary sweetness exposure and weight gain. Therefore, longer term,
      sufficiently-powered studies with a 'whole diet' approach are needed to address the question
      whether sweet preferences can be altered (suppressed or stimulated) by variations in
      sweetness exposure. It is important to answer this question so that dietary recommendations
      can be scientifically tailored accordingly. The present study will provide breakthrough
      evidence about the flexibility/adaptability of sweetness preferences, in terms of effect
      sizes and direction, duration of effects, and impact on dietary intake, glucose homeostasis
      and body weight. This information is particularly relevant for product development by food
      industries in the context of reformulation strategies, and for governments to base their
      dietary guidelines upon.

      The primary study objective is to assess the effect of a 6-month low, regular and high
      dietary sweetness exposure on sweetness preference in a series of familiar and unfamiliar
      foods. Preference will be assessed in both familiar and unfamiliar foods since, preferences
      in familiar, commonly eaten foods might by harder to change compared to those for unfamiliar
      foods, because there is no consumer-expected sweetness level associated with unfamiliar
      foods. The secondary objective is to assess the effect of a 6-month low, regular and high
      dietary sweetness exposure on sweetness perception, food choice and intake during a test
      meal, dietary taste patterns, taste preferences, food cravings, sweet-liker type, glucose
      homeostasis, biomarkers related to cardiovascular disease (CVD) and diabetes, body weight and
      body composition. Participants will be matched on age, gender, BMI and sweet liker status and
      randomly allocated to one of the three intervention arms: (1) regular dietary sweetness
      exposure (25-30 percent daily energy from sweet foods) (control) (n=60); (2) low dietary
      sweetness exposure (10-15 percent daily energy from sweet foods) (n=60); and (3) high dietary
      sweetness exposure (40-45 percent daily energy from sweet foods) (n=60). The intervention is
      semi-controlled, meaning that 50 percent of the foods will be provided to participants. Foods
      are offered ad libitum, on a weekly basis and macronutrient composition of the offered foods
      is similar in energy and macronutrient composition, that is fat, protein, carbohydrates and
      fibres, but different in sweetness. New methodology of our group enables us to assess
      sweetness exposure within a diet, by profiling foods based on six taste clusters (neutral;
      salt, umami & fat; sweet and fat; sweet and sour; fat; bitter).

      Preference and perceived taste intensity will be assessed during hedonic and sensory
      evaluation of eight foods; three sweet familiar, three sweet unfamiliar and two salty
      familiar ones. Foods are solid, semi-solid and liquid. Furthermore, observed food choice and
      intake during test meals, reported food preferences, reported food cravings, sweet-liker
      type, glucose homeostasis, body weight, body composition and biomarkers related to diabetes
      and cardiovascular disease will be assessed. Outcomes will be assessed several times; at
      baseline (Month 0), during the intervention Month 1, Month 3, Month 6 and in the follow up
      period (Month 7, Month 10). Compliance will be assessed with 24-hour urine sample and dietary
      assessment methods (24-hour recalls).
allocation: Randomized
intervention model: Parallel Assignment
intervention model description: Randomised controlled intervention study
primary purpose: Basic Science
masking: Double (Participant, Investigator)
measure: Change in preference score.
time frame: from month 0 to month 6.
description: Measured during preference testing, using Ranking on a scale methodology (scale anchored at 0: Dislike extremely; 50: Neither dislike or like; 100: Like extremely) in a series of test foods.
measure: Change in preference score.
time frame: from month 0 to month 1, 3, 7 ad 10.
description: Measured during preference testing, using Ranking on a scale methodology (scale anchored at 0: Dislike extremely; 50: Neither dislike or like; 100: Like extremely) in a series of test foods.
measure: Difference in mean liking scores between familiar and unfamiliar foods.
time frame: Measured at 0, 1, 3, 6, 7 and 10 months.
description: Measured during preference testing, using Ranking on a scale methodology (scale anchored at 0: Dislike extremely; 50: Neither dislike or like; 100: Like extremely) in a series of test foods.
measure: Change in sensory intensity scores.
time frame: Measured at 0, 1, 3, 6, 7 and 10 months.
description: Measured during sensory testing, using 100-unit Visual analogue scale (VAS), (anchored at 0: not sweet/salty at all; 100: Extremely sweet/salty) in a series of test foods.
measure: Change in energy intake.
time frame: Measured at 0, 1, 3, 6, 7 and 10 months.
description: Measured during ad-libitum test meal in kcal.
measure: Change in energy intake.
time frame: Measured at 0, 1, 3, 6, 7 and 10 months.
description: Measured during ad-libitum test meal in kJ.
measure: Proportion of eaten sweet foods vs. foods from other taste modalities.
time frame: Measured at 0, 1, 3, 6, 7 and 10 months
description: Measured during ad-libitum test meal in proportions.
measure: Sweet-liker status score.
time frame: Measured at 0, 1, 3, 6, 7 and 10 months.
description: Measured on a 100-unit VAS scale (anchored at 0: Dislike; 100: Like).
measure: Food craving questionnaire scores.
time frame: Measured at 0, 1, 3, 6, 7 and 10 months.
description: Measured using the Control of eating questionnaire (CoEQ)
measure: Taste preference questionnaire scores.
time frame: Measured at 0, 1, 3, 6, 7 and 10 months.
description: Measured using Taste Preference questionnaire (PrefQuest).
measure: Dietary taste patterns.
time frame: Measured at 0, 1, 3, 6, 7 and 10 months.
description: Measured with the Taste food frequency questionnaire in frequency.
measure: Dietary taste patterns.
time frame: Measured at 0, 1, 3, 6, 7 and 10 months.
description: Measured with the Taste food frequency questionnaire in % of energy coming from each taste cluster.
measure: Dietary taste patterns.
time frame: Measured at 0, 1, 3, 6, 7 and 10 months.
description: Measured with the Taste food frequency questionnaire in % of food weight coming from each taste cluster.
measure: Body weight.
time frame: Measured at 0, 1, 2, 3, 4, 5, 6, 7 and 10 months.
description: Measured with a weighing scale in kg.
measure: Waist-to-hip ratio.
time frame: Measured at 0, 1, 3, 6, 7 and 10 months.
description: Measured using a stretch-resistant tape.
measure: % of body fat mass and lean body mass (fat free mass).
time frame: Measured at 0, 6 and 10 months.
description: Measured with a dual energy x-ray absorptiometry (DEXA).
measure: Variation in interstitial glucose levels.
time frame: Measured at 0, 6 and 10 months.
description: Measured with glucose monitoring sensor (only measured in a subgroup, of 60 subjects, 20 per intervention arm).
measure: Change in fasting glucose, insulin, total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides levels in blood.
time frame: Measured at 0, 1, 3, 6, 7 and 10 months.
description: Measured in blood in mmol/L.
measure: Adverse events.
time frame: Measured at 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10 months.
description: Self-reported and monitored.
measure: Concentration of biomarkers in urine related to sugar, low and no calorie sweeteners, protein and salt intake.
time frame: Measured at 0, 1, 3, 6, 7 and 10 months.
description: Measured in urine in mg/d.
measure: Intake levels of foods, food groups and macronutrients.
time frame: Measured at 0, 1, 2, 3, 4, 5, 6, 7 and 10 months.
description: Measured with 24-hour recalls, in kcal/day.
measure: Intake levels of foods, food groups and macronutrients.
time frame: Measured at 0, 1, 2, 3, 4, 5, 6, 7 and 10 months.
description: Measured with 24-hour recalls, in kJ/day.
measure: Intake levels of foods, food groups and macronutrients.
time frame: Measured at 0, 1, 2, 3, 4, 5, 6, 7 and 10 months.
description: Measured with 24-hour recalls, in g/day.
measure: Gender.
time frame: Assessed at month 0.
description: Self-reported.
measure: Height.
time frame: Assessed at month 0.
description: Measured with a stadiometer.
measure: Physical activity level.
time frame: Measured at 0, 1, 3, 6, 7 and 10 months.
description: Measured with the Short Questionnaire to Assess Health enhancing physical activity (SQUASH).
measure: Polymorphisms in the genes related to the sweet taste perception.
time frame: Assessed at month 0.
description: Genes will be extracted from collected blood samples.
measure: Age.
time frame: Assessed at month 0.
description: Self-reported.
measure: Medicine usage.
time frame: Assessed at month 0.
description: Number and type of medicine used, self-reported.
arm group label: Regular dietary sweetness exposure - Control
arm group type: Active Comparator
description: Regular dietary sweetness exposure (RSE) - The RSE group consumes a diet with 25 - 30 % energy from sweet tasting foods, for 6 months.
arm group label: Low dietary sweetness exposure - Experimental
arm group type: Experimental
description: Low dietary sweetness exposure (LSE) - The LSE group consumes a diet with 10 - 15 % energy from sweet tasting foods, for 6 months.
arm group label: High dietary sweetness exposure - Experimental
arm group type: Experimental
description: High dietary sweetness exposure (HSE) - The HSE group consumes a diet with 40 - 45 % energy from sweet tasting foods, for 6 months.
intervention type: Other
intervention name: Dietary intervention
description: Varying the exposure to sweetness via diet manipulation.
arm group label: High dietary sweetness exposure - Experimental
arm group label: Low dietary sweetness exposure - Experimental
arm group label: Regular dietary sweetness exposure - Control
criteria: 
gender: All
minimum age: 18 Years
maximum age: 65 Years
healthy volunteers: Accepts Healthy Volunteers
last name: Kees de Graaf
role: Study Chair
affiliation: WU
last name: Monica Mars
role: Principal Investigator
affiliation: WU
last name: Eva Marija Cad, MSc
phone: +31317488077
email: eva.cad@wur.nl
facility: 
status: Recruiting
contact: 
country: Netherlands
responsible party type: Sponsor
sharing ipd: Yes
ipd description: Individual participant data that underline the results reported in an article after de-identification will be shared.
ipd info type: Study Protocol
ipd info type: Statistical Analysis Plan (SAP)
ipd info type: Analytic Code
ipd time frame: Immediately following the publication. No end date.
ipd access criteria: Anyone who wishes to access the data. Individuals who wish to use the data for secondary analysis must contact corresponding authors of respective/specific publications for their approval. They must also reference the source of the data to provide appropriate credit to those who generated it and allow searching for the studies it has supported.