Diet, HealthyNCT05399836
SSS and the Impact of Portion Size on Daily Energy Intake
A study testing Portion size manipulation in people with Diet, Healthy and Eating Behavior, run by University of Liverpool at 1 site in United Kingdom.
Trial summary
Reducing food portion size is a potential strategy to reduce energy intake. However, it remains unclear who is most susceptible to the portion size effect (PSE). There are just two studies which have examined the PSE in the context of socioeconomic position (SEP), with mixed findings. Read more about this study
- Who is it for?
- Ages 18 years and older, women onlyHealthy volunteers can take part
- Conditions the study is for
- Diet, Healthy, Eating Behavior, Obesity
- What is being tested?
- Portion size manipulation
- Type of treatment
- Lifestyle or therapy programme
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 47 participants
- Where
- 1 siteUnited Kingdom
- Study dates
- 30 May 2022to 12 Oct 2022
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- Women only
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Female
- UK (United Kingdom) residents, able to visit laboratory in Liverpool
- Aged 18 or over
- Fluent in English
- willing to consume the test foods
- Self report willingness to eat test foods
- BMI between 18.5 - 32.5kg2
Who cannot join
- participation in our previous study
- food allergies, intolerances or specific dietary requirements (except vegetarian)
- taking medication which affects appetite
- currently pregnant
- history of eating disorders
- currently on a diet to lose weight
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Subjective Social Status and the Effect of Portion Size Reduction: a 1-day Dietary Behaviour Experimental Study
Reducing food portion size is a potential strategy to reduce energy intake. However, it remains unclear who is most susceptible to the portion size effect (PSE). There are just two studies which have examined the PSE in the context of socioeconomic position (SEP), with mixed findings. In an online trial the PSE on intended consumption of unhealthy snacks was 18-24% larger for participants of lower SEP compared to participants of higher SEP. However, in a recent laboratory study which examined the PSE on total daily energy intake, participants of lower SEP were no more susceptible to the influence of portion size on eating behaviour than participants of higher SEP. Further research is required to elucidate these divergent findings.
There is also an absence of evidence examining the moderating role of subjective social status (SSS) - an individual's perceived standing in society - on the PSE. Given evidence that the subjective experience of social class may be associated with health outcomes, the present study examines whether reductions to the portion size reduces daily energy intake, and whether and how SSS (higher vs lower) moderates the PSE.
In a crossover experiment, participants will be served all meals in the lab on two separate days, with the portion size of main components at breakfast, lunch and dinner manipulated (i.e. smaller on one day vs larger on the other day). All other foods offered are identical. Food intake from the portion-manipulated breakfast, lunch and dinner, as well as all other meal components (non-portion-manipulated sides, dessert, seconds, snacks, etc.) will be measured, to assess total daily energy intake (kcal).
Read the detailed description
See Study Protocol attached.
- Conditions
- Diet, Healthy, Eating Behavior, Obesity
- Being tested
- Portion size manipulation
- Keywords
- portion size, socio-economic position, eating behaviour
- Medical subject headings
- Feeding Behavior, Obesity
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Portion size manipulationBehavioural
The intervention will be administered via changing portion sizes of foods served to participants.
| Study group | Role | What they receive |
|---|---|---|
| Larger portions | Experimental | the main meal component (lunch/dinner) served to participants in the laboratory, reflecting 100% portion. All other foods are identical across conditions (e.g. sides, seconds, dessert, snacks). Receives: Behavioral: Portion size manipulation |
| Smaller portions | Experimental | the main meal component (lunch/dinner) served to participants in the laboratory, reflecting 66% portion (i.e. reduced portion size). All other foods are identical across conditions (e.g. sides, seconds, dessert, snacks). Receives: Behavioral: Portion size manipulation |
What is being measured
The primary outcome is the main question the study is designed to answer.
Daily energy intake
Total energy (kcal) consumed from breakfast, lunch, dinner, dessert, snackbox, and any self-reported additional foods.
Measured: Time Frame: 24 hours after intervention administered
Secondary outcomes (2)
Energy intake from portion-manipulated foods
Total energy (kcal) consumed from portion-manipulated foods at breakfast, lunch, and dinner
Measured: Time Frame: 24 hours after intervention administered
Energy intake from non portion-manipulated foods
Total energy (kcal) consumed from other foods (no portion-manipulation) at breakfast, lunch, dinner, snacks, and self-reported foods.
Measured: Time Frame: 24 hours after intervention administered
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted1 Jun 2022
- Study start30 May 2022
- Primary completion12 Oct 2022
- Study completion12 Oct 2022
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Diet, HealthyStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Single blind
- Who is masked
- Participant
- Enrolment
- 47 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Liverpool
- Sponsor type
- University, hospital or other
- Collaborators
- European Research Council
- Responsible party
- Principal investigator, Eric Robinson, University of Liverpool
- Investigators
- Eric Robinson, PhD, Principal investigator, University of Liverpool
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05399836
- Sponsor's protocol ID
- 803194 SSS PSE
- Status last verified
- Jan 2023
- First submitted
- 26 May 2022
- Last updated
- 10 Jan 2023
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: Study data (anonymised) will be shared on the Open Science Framework (OSF)
Publications
Langfield T, Clarke K, Marty L, Jones A, Robinson E. Socioeconomic position and the influence of food portion size on daily energy intake in adult females: two randomized controlled trials. Int J Behav Nutr Phys Act. 2023 Apr 27;20(1):53. doi: 10.1186/s12966-023-01453-x.
PubMed 37101143
Study at a glance
From the registry record, last updated by the sponsor on 10 Jan 2023. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Subjective Social Status and the Effect of Portion Size Reduction: a 1-day Dietary Behaviour Experimental Study
- ClinicalTrials.gov ID
- NCT05399836
- Acronym / sponsor ID
- 803194 SSS PSE
- Conditions
- Diet, Healthy, Eating Behavior, Obesity
- Keywords
- portion size, socio-economic position, eating behaviour
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 47 participants (actual)
- Lead sponsor
- University of LiverpoolUniversity, hospital or other
- Collaborators
- European Research Council
- Study start
- 30 May 2022 (actual)
- Primary completion
- 12 Oct 2022 (actual)
- Study completion
- 12 Oct 2022 (actual)
- First posted
- 1 Jun 2022 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Reducing food portion size is a potential strategy to reduce energy intake. However, it remains unclear who is most susceptible to the portion size effect (PSE). There are just two studies which have examined the PSE in the context of socioeconomic position (SEP), with mixed findings. In an online trial the PSE on intended consumption of unhealthy snacks was 18-24% larger for participants of lower SEP compared to participants of higher SEP. However, in a recent laboratory study which examined the PSE on total daily energy intake, participants of lower SEP were no more susceptible to the influence of portion size on eating behaviour than participants of higher SEP. Further research is required to elucidate these divergent findings.
There is also an absence of evidence examining the moderating role of subjective social status (SSS) - an individual's perceived standing in society - on the PSE. Given evidence that the subjective experience of social class may be associated with health outcomes, the present study examines whether reductions to the portion size reduces daily energy intake, and whether and how SSS (higher vs lower) moderates the PSE.
In a crossover experiment, participants will be served all meals in the lab on two separate days, with the portion size of main components at breakfast, lunch and dinner manipulated (i.e. smaller on one day vs larger on the other day). All other foods offered are identical. Food intake from the portion-manipulated breakfast, lunch and dinner, as well as all other meal components (non-portion-manipulated sides, dessert, seconds, snacks, etc.) will be measured, to assess total daily energy intake (kcal).
Detailed description
See Study Protocol attached.
Study design
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Single blind (participant)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Larger portions | Experimental | Behavioral: Portion size manipulationthe main meal component (lunch/dinner) served to participants in the laboratory, reflecting 100% portion. All other foods are identical across conditions (e.g. sides, seconds, dessert, snacks). |
| Smaller portions | Experimental | Behavioral: Portion size manipulationthe main meal component (lunch/dinner) served to participants in the laboratory, reflecting 66% portion (i.e. reduced portion size). All other foods are identical across conditions (e.g. sides, seconds, dessert, snacks). |
Who may qualify
- Ages
- 18 years and older
- Sex
- Female only
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (7 listed)
- Female
- UK (United Kingdom) residents, able to visit laboratory in Liverpool
- Aged 18 or over
- Fluent in English
- willing to consume the test foods
Key exclusion criteria (6 listed)
- participation in our previous study
- food allergies, intolerances or specific dietary requirements (except vegetarian)
- taking medication which affects appetite
- currently pregnant
- history of eating disorders
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Portion size manipulationThe intervention will be administered via changing portion sizes of foods served to participants. | Behavioural | Larger portions, Smaller portions |
Primary outcome
Daily energy intake
Time frame: Time Frame: 24 hours after intervention administered
Total energy (kcal) consumed from breakfast, lunch, dinner, dessert, snackbox, and any self-reported additional foods.
2 secondary outcomes
Energy intake from portion-manipulated foods
Time frame: Time Frame: 24 hours after intervention administered
Energy intake from non portion-manipulated foods
Time frame: Time Frame: 24 hours after intervention administered
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 10 Jan 2023.
- Derived from this study: PubMed 37101143Langfield T, Clarke K, Marty L, Jones A, Robinson E. Socioeconomic position and the influence of food portion size on daily energy intake in adult females: two randomized controlled trials. Int J Behav Nutr Phys Act. 2023 Apr 27;20(1):53. doi: 10.1186/s12966-023-01453-x.
- Individual participant dataSharing planned: Yes. Study data (anonymised) will be shared on the Open Science Framework (OSF)
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Eric Robinson, PhD principal investigator
University of Liverpool
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Portion size manipulation in people with Diet, Healthy and Eating Behavior, run by University of Liverpool at 1 site in United Kingdom.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 7 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 10 Jan 2023. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United Kingdom. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Daily energy intake (time frame: Time Frame: 24 hours after intervention administered). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT05399836, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 10 Jan 2023.