Bariatric Surgery CandidateNCT06461247
Compliance With Standard Care vs Ready to Eat Meals Prior to Bariatric Surgery
A study testing Very Low Calorie Diet Ready-to-eat (VLCD RTE) meals in people with Bariatric Surgery Candidate, run by National University Hospital, Singapore at 2 sites in Singapore.
Trial summary
Currently, a ketosis-inducing programme, usually a liquid meal replacement, is the standard of care for pre-operative dietary management. However, compliance with liduiqd meal replacement is challenging primarily due to individual taste preferences, limited variety, having to take a liquid diet, lifestyle factors, and… Read more about this study
- Who is it for?
- Ages 21 to 65 yearsHealthy volunteers can take part
- Conditions the study is for
- Bariatric Surgery Candidate
- What is being tested?
- Very Low Calorie Diet Ready-to-eat (VLCD RTE) meals
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 140 participants
- Where
- 2 sitesSingapore
- Study dates
- 1 Jul 2024to Sep 2026
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
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 21 to 65 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Adults aged 21 to 65 years old
- Scheduled for bariatric surgery at least 1 month prior
- BMI ≥ 27.5 kg/m2 (with type 2 diabetes mellitus or metabolic syndrome)
- Owns a smart phone with data plan
- English speaking
Who cannot join
- Cognitive impairment.
- Hypothyroidism
- Chronic kidney disease
- Hypothyroidism
- Depression with ongoing psychology follow up
- Type 1 diabetes
Show all 13Show fewer
- Liver Cirrhosis
- Pregnancy
- Heart Failure
- Active cancer or in remission for less than 5 years
- Vegetarian
- Observing the fast during the month of Ramadan
- Undergoing treatment with anti obesity medications (eg: Phentermine/Orlistat/Contrave/GLP-1 analogues etc)
Trial locations and contacts
2 sites in 1 country. Contact the study team or a site near you to ask about taking part.
Singapore2 sites, 2 recruiting
- Recruiting
Alexandra Hospital
Singapore
Melissa Tay
- Recruiting
National University Hospital
Singapore
Melissa Tay
About this study
Official title: Compliance With Standard Care vs Ready to Eat Meals Prior to Bariatric Surgery - a Randomised Controlled Trial
Currently, a ketosis-inducing programme, usually a liquid meal replacement, is the standard of care for pre-operative dietary management. However, compliance with liduiqd meal replacement is challenging primarily due to individual taste preferences, limited variety, having to take a liquid diet, lifestyle factors, and other obstacles. Therefore, there is a need for RTE meals to enhance patient satisfaction and compliance, ultimately resulting in improved pre-operative weight loss outcomes. Hence, this RCT study aims to determine whether Very Low Calorie Diet Ready-to-eat (VLCD RTE) meals would lead to greater compliance as measured by blood ketones and meal logging via Nutritionist Buddy app (nBuddy App) compared to standard care liquid meal replacement (Optifast) prior to bariatric surgery.
Read the detailed description
The obesity rate in Singapore is rising, mirroring a similar worrying global trend. Bariatric surgery has been the only long-term method proven to overcome severe obesity and it has become an increasingly common and effective treatment option. Preoperative weight loss is required to reduce cardiovascular risk, liver volume and decrease intra-abdominal fat. This leads to enhanced surgical visibility and surgical access resulting in reduced intra- and postoperative complications.
Currently, a ketosis-inducing programme, usually a liquid meal replacement, is the standard of care for pre-operative dietary management. However, compliance with liquid meal replacement is challenging primarily due to individual taste preferences, limited variety, having to take a liquid diet, lifestyle factors, and other obstacles. It was found for taste and gastrointestinal side effects to be the main issues.
Therefore, RTE meals are carefully formulated to provide the calculated calorie, controlled net carbohydrate content, and are low in saturated and trans fat. By incorporating these meals as a VLCD diet regime, it would allow patients to still enjoy the chewing sensation and local favourites and flavours, while enjoying mealtime with their friends and families.
In this randomised controlled trial, patients listed for bariatric surgery from the NUH Weight Management Clinic in Singapore will undergo randomization into either the Standard Care or Intervention group during the baseline visit.
- Standard Care Group (n=70): Participants will be provided with liquid meal replacements for breakfast, lunch, and dinner for 4 weeks. Additionally, patients are to prepare 1 serving of non-starchy vegetables are to be included for lunch and dinner.
- Intervention Group (n=70): Participants will be provided with the VLCD RTE meals for lunch and dinner for 4 weeks and advised on a healthy keto breakfast.
All eligible participants (n=140) will be advised to keep within the 800 calorie limit and 50g net carbohydrate limit per day. They will receive guidance from a dietitian on lifestyle changes and pre-bariatric surgery VLCD diets. Participants in both groups will also be advised to download the nutritionist Buddy Keto app for monitoring of compliance, food intake, steps count, weight progress and in app virtual reminders (automated and by dietitians via the chat function).
- Conditions
- Bariatric Surgery Candidate
- Being tested
- Very Low Calorie Diet Ready-to-eat (VLCD RTE) meals, Standard Care Group
- Keywords
- Weight loss, Very Low Calorie Diet, Body Weight
- Medical subject headings
- Weight Loss, Body Weight
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Very Low Calorie Diet Ready-to-eat (VLCD RTE) mealsOther
Participants will be provided with VLCD RTE meals for lunch and dinner for 4 weeks and advised on a healthy ketogenic breakfast. Participant will be expected to adhere to VLCD regimen containing 800 calories per day or fewer and keep within 50g net carbohydrates a day.
Standard Care GroupOther
Participants will be provided with liquid meal replacement for breakfast, lunch, and dinner for 4 weeks. Additionally, patients are to prepare 1 serving of non-starchy vegetables are to be included for lunch and dinner. Participant will be expected to adhere to VLCD regimen containing 800 calories per day or fewer and keep within 50g net carbohydrates a day.
| Study group | Role | What they receive |
|---|---|---|
| Very Low Calorie Diet Ready-to-eat (VLCD RTE) meals | Experimental | Participants (n=70) in the VLCD RTE meals group will be advised to follow a calorie-restricted healthy ketogenic diet , consuming a maximum of 800 calories and 50g net carbohydrate intake daily.
Participants will be provided with VLCD RTE meals for lunch and dinner for 4 weeks and advised on a healthy keto breakfast.
The participants will be expected to self-monitor their weight, physical activity and diet logs via the nutritionist buddy keto app. There will be in app virtual reminders (automated and by dietitians via the chat function) sent via the nutritionist buddy keto application for the 1 month for participants to log in their weight and meals. Receives: Other: Very Low Calorie Diet Ready-to-eat (VLCD RTE) meals |
| Liquid Meal Replacement | Active comparator | Participants (n=70) in the liquid meal replacement group will be advised to follow very low-calorie diet, with a maximum of 800 calories and 50g net carbohydrate intake daily.
Participants will be provided with a liquid meal replacement for breakfast, lunch, and dinner for 4 weeks. Additionally, patients are to prepare 1 serving of non-starchy vegetables are to be included for lunch and dinner.
The participants will be expected to self-monitor their weight, physical activity and diet logs via the nutritionist buddy keto app. There will be in app virtual reminders (automated and by dietitians via the chat function) sent via the nutritionist buddy keto application for the 1 month for participants to log in their weight and meals. Receives: Other: Standard Care Group |
What is being measured
The primary outcome is the main question the study is designed to answer.
Compliance rate of the RTE meals
The compliance rate is assessed via food logging in the nutritionist buddy keto app
Measured: Daily for intervention period of 28 days
Blood Ketones Measurement
Fasting blood ketone measurements measured at study visit
Measured: 1st week, 2nd week, 3rd week, 4th week, surgery day
Secondary outcomes (2)
Satisfaction of the RTE meals
Assessed via a self-reported questionnaire with a numeric scale of 1 to 5
Measured: 3rd week and surgery day
Weight Change
Weight changes at study visit
Measured: 1st week, 2nd week, 3rd week, 4th week, surgery day
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted14 Jun 2024
- Study start1 Jul 2024
- Primary completionSep 2026 (estimated)
- Study completionSep 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Bariatric Surgery CandidateStudies of the same condition, open and under way.
- More trials run by National University Hospital, SingaporeThe sponsor's other registered studies.
- 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
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Standard Care Group (n=70): Participants will be having liquid meal replacement for breakfast, lunch, and dinner for 4 weeks. Additionally, patients are to prepare 1 serving of non-starchy vegetables are to be included for lunch and dinner. Intervention Group (n=70): Participants will be provided with VLCD RTE meals for lunch and dinner for 4 weeks and advised on a healthy keto breakfast. Both groups will be recommended to keep within the calorie limit to 800kcal and 50g net carbohydrates per day.
- Masking
- None (open label)
- Enrolment
- 140 participants (estimated)
Sponsor and investigators
- Lead sponsor
- National University Hospital, Singapore
- Sponsor type
- University, hospital or other
- Collaborators
- Alexandra Hospital
- Responsible party
- Sponsor
- Investigators
- Melissa Tay, Principal investigator, National University Hospital, Singapore
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06461247
- Sponsor's protocol ID
- 2024/00240
- Status last verified
- Sep 2025
- First submitted
- 5 Jun 2024
- Last updated
- 12 Sep 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: Individual participant data will remain confidential and only accessible via lock and keys by the researchers.
Study at a glance
From the registry record, last updated by the sponsor on 12 Sep 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Compliance With Standard Care vs Ready to Eat Meals Prior to Bariatric Surgery - a Randomised Controlled Trial
- ClinicalTrials.gov ID
- NCT06461247
- Acronym / sponsor ID
- 2024/00240
- Conditions
- Bariatric Surgery Candidate
- Keywords
- Weight loss, Very Low Calorie Diet, Body Weight
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 140 participants (estimated)
- Lead sponsor
- National University Hospital, SingaporeUniversity, hospital or other
- Collaborators
- Alexandra Hospital
- Study start
- 1 Jul 2024 (actual)
- Primary completion
- Sep 2026 (estimated)
- Study completion
- Sep 2026 (estimated)
- First posted
- 14 Jun 2024 (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.
Currently, a ketosis-inducing programme, usually a liquid meal replacement, is the standard of care for pre-operative dietary management. However, compliance with liduiqd meal replacement is challenging primarily due to individual taste preferences, limited variety, having to take a liquid diet, lifestyle factors, and other obstacles. Therefore, there is a need for RTE meals to enhance patient satisfaction and compliance, ultimately resulting in improved pre-operative weight loss outcomes. Hence, this RCT study aims to determine whether Very Low Calorie Diet Ready-to-eat (VLCD RTE) meals would lead to greater compliance as measured by blood ketones and meal logging via Nutritionist Buddy app (nBuddy App) compared to standard care liquid meal replacement (Optifast) prior to bariatric surgery.
Detailed description
The obesity rate in Singapore is rising, mirroring a similar worrying global trend. Bariatric surgery has been the only long-term method proven to overcome severe obesity and it has become an increasingly common and effective treatment option. Preoperative weight loss is required to reduce cardiovascular risk, liver volume and decrease intra-abdominal fat. This leads to enhanced surgical visibility and surgical access resulting in reduced intra- and postoperative complications.
Currently, a ketosis-inducing programme, usually a liquid meal replacement, is the standard of care for pre-operative dietary management. However, compliance with liquid meal replacement is challenging primarily due to individual taste preferences, limited variety, having to take a liquid diet, lifestyle factors, and other obstacles. It was found for taste and gastrointestinal side effects to be the main issues.
Therefore, RTE meals are carefully formulated to provide the calculated calorie, controlled net carbohydrate content, and are low in saturated and trans fat. By incorporating these meals as a VLCD diet regime, it would allow patients to still enjoy the chewing sensation and local favourites and flavours, while enjoying mealtime with their friends and families.
In this randomised controlled trial, patients listed for bariatric surgery from the NUH Weight Management Clinic in Singapore will undergo randomization into either the Standard Care or Intervention group during the baseline visit.
- Standard Care Group (n=70): Participants will be provided with liquid meal replacements for breakfast, lunch, and dinner for 4 weeks. Additionally, patients are to prepare 1 serving of non-starchy vegetables are to be included for lunch and dinner.
- Intervention Group (n=70): Participants will be provided with the VLCD RTE meals for lunch and dinner for 4 weeks and advised on a healthy keto breakfast.
All eligible participants (n=140) will be advised to keep within the 800 calorie limit and 50g net carbohydrate limit per day. They will receive guidance from a dietitian on lifestyle changes and pre-bariatric surgery VLCD diets. Participants in both groups will also be advised to download the nutritionist Buddy Keto app for monitoring of compliance, food intake, steps count, weight progress and in app virtual reminders (automated and by dietitians via the chat function).
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- Standard Care Group (n=70): Participants will be having liquid meal replacement for breakfast, lunch, and dinner for 4 weeks. Additionally, patients are to prepare 1 serving of non-starchy vegetables are to be included for lunch and dinner. Intervention Group (n=70): Participants will be provided with VLCD RTE meals for lunch and dinner for 4 weeks and advised on a healthy keto breakfast. Both groups will be recommended to keep within the calorie limit to 800kcal and 50g net carbohydrates per day.
| Arm | Type | Receives |
|---|---|---|
| Very Low Calorie Diet Ready-to-eat (VLCD RTE) meals | Experimental | Other: Very Low Calorie Diet Ready-to-eat (VLCD RTE) mealsParticipants (n=70) in the VLCD RTE meals group will be advised to follow a calorie-restricted healthy ketogenic diet , consuming a maximum of 800 calories and 50g net carbohydrate intake daily. Participants will be provided with VLCD RTE meals for lunch and dinner for 4 weeks and advised on a healthy keto breakfast. The participants will be expected to self-monitor their weight, physical activity and diet logs via the nutritionist buddy keto app. There will be in app virtual reminders (automated and by dietitians via the chat function) sent via the nutritionist buddy keto application for the 1 month for participants to log in their weight and meals. |
| Liquid Meal Replacement | Active comparator | Other: Standard Care GroupParticipants (n=70) in the liquid meal replacement group will be advised to follow very low-calorie diet, with a maximum of 800 calories and 50g net carbohydrate intake daily. Participants will be provided with a liquid meal replacement for breakfast, lunch, and dinner for 4 weeks. Additionally, patients are to prepare 1 serving of non-starchy vegetables are to be included for lunch and dinner. The participants will be expected to self-monitor their weight, physical activity and diet logs via the nutritionist buddy keto app. There will be in app virtual reminders (automated and by dietitians via the chat function) sent via the nutritionist buddy keto application for the 1 month for participants to log in their weight and meals. |
Who may qualify
- Ages
- 21 to 65 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- Adults aged 21 to 65 years old
- Scheduled for bariatric surgery at least 1 month prior
- BMI ≥ 27.5 kg/m2 (with type 2 diabetes mellitus or metabolic syndrome)
- Owns a smart phone with data plan
- English speaking
Key exclusion criteria (13 listed)
- Cognitive impairment.
- Hypothyroidism
- Chronic kidney disease
- Hypothyroidism
- Depression with ongoing psychology follow up
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 |
|---|---|---|
| Very Low Calorie Diet Ready-to-eat (VLCD RTE) mealsParticipants will be provided with VLCD RTE meals for lunch and dinner for 4 weeks and advised on a healthy ketogenic breakfast. Participant will be expected to adhere to VLCD regimen containing 800 calories per day or fewer and keep within 50g net carbohydrates a day. | Other | Very Low Calorie Diet Ready-to-eat (VLCD RTE) meals |
| Standard Care GroupParticipants will be provided with liquid meal replacement for breakfast, lunch, and dinner for 4 weeks. Additionally, patients are to prepare 1 serving of non-starchy vegetables are to be included for lunch and dinner. Participant will be expected to adhere to VLCD regimen containing 800 calories per day or fewer and keep within 50g net carbohydrates a day. | Other | Liquid Meal Replacement |
Primary outcome
Compliance rate of the RTE meals
Time frame: Daily for intervention period of 28 days
The compliance rate is assessed via food logging in the nutritionist buddy keto app
Blood Ketones Measurement
Time frame: 1st week, 2nd week, 3rd week, 4th week, surgery day
Fasting blood ketone measurements measured at study visit
2 secondary outcomes
Satisfaction of the RTE meals
Time frame: 3rd week and surgery day
Weight Change
Time frame: 1st week, 2nd week, 3rd week, 4th week, surgery day
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 12 Sep 2025.
- Individual participant dataSharing planned: No. Individual participant data will remain confidential and only accessible via lock and keys by the researchers.
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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.
Melissa Tay principal investigator
National University Hospital, Singapore
2 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Very Low Calorie Diet Ready-to-eat (VLCD RTE) meals in people with Bariatric Surgery Candidate, run by National University Hospital, Singapore at 2 sites in Singapore.
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 5 inclusion and 13 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: looking for participants now, as of the sponsor's last update on 12 Sep 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in Singapore. 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?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Melissa Tay Hui Juan (67725166, melissa_hj_tay@nuhs.edu.sg), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Compliance rate of the RTE meals (time frame: Daily for intervention period of 28 days). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 12 Sep 2025.