AzTrials
AzTrials

Obesity (Disorder)BariaGut TasteNCT07268508

Impact of a Pro-diversity Gut Microbiota Diet After a Bariatric Surgery on Gut Microbiota, Eating Behaviour and Sensory Function

A study testing Nutritional counseling in people with Obesity (Disorder) and Bariatric Surgery, run by Hospices Civils de Lyon at 3 sites in France.

Recruiting

Looking for participants now. Contact the study team or a site below to ask about taking part.

Sites and contacts
Official record
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Trial summary

Bariatric surgery is the most effective treatment for long-term weight loss and reducing obesity-related health risks. It alters the gastrointestinal tract as well as metabolic and hormonal functions, influencing eating behaviour. Read more about this study

Who is it for?
Ages 25 to 65 years
Conditions the study is for
Obesity (Disorder), Bariatric Surgery
What is being tested?
Nutritional counseling
Could I receive a placebo?
No, everyone receives an active treatment
How many people
60 participants
Where
3 sitesFrance
Study dates
5 Nov 2025to 5 Apr 2029
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 25 to 65 years
  • All sexes
  • No healthy volunteers
  • Adult, Older adult

Who may be able to join

  • Between 25 and 65 years old
  • Undergoing either sleeve gastrectomy or Roux-en-Y gastric bypass
  • With grade 3 obesity (BMI≥40 kg/m²) or with BMI≥35 kg/m² and at least one comorbidity likely to be improved after surgery, with the exception of type 2 diabetes
  • Signed consent form
  • Living less than an hour and 30 minutes from the hospital
  • Presence of effective and stable contraception for women of childbearing potential

Who cannot join

  • Type 2 diabetes
  • Presence of a contraindication to bariatric surgery
  • Presence of gastrointestinal pathologies with an inflammatory component, known gastroparesis, total gastrectomy, colectomy, exocrine pancreatic insufficiency, known endocrine pathologies inducing hyperglycaemia (uncontrolled dysthyroidism, acromegaly, hypercorticism, etc.), severe chronic renal insufficiency (< 30mL/min), or hepatocellular insufficiency
  • Claustrophobic
  • Pregnant or breastfeeding women
  • Taking an obesity treatment 3 months before surgery
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  • Taking a corticoids, immunosuppression, anabolizing, or growing hormones, antibody treatments less than 3 months before inclusion
  • Daily taking of laxatives or drugs that can strongly interfere with the composition of the intestinal microbiota. If taken sporadically, the patient can be included at a distance (3 weeks) from the laxatives taken.
  • Specific diets (vegetarian, vegan or without gluten)
  • No French speaker
  • Already included in other study
  • Donated blood in the last two months
  • Without freezer access
  • With allergy or intolerance to food propose in ad libitum buffet

Trial locations and contacts

3 sites in 1 country. Contact the study team or a site near you to ask about taking part.

Berenice SEGRESTIN contact

France3 sites, 3 recruiting
  • Hospital Edouard Herriot, digestive surgery department

    Lyon, 69310

    Maud ROBERT, +33 4 72 11 62 63, maud.robert@chu-lyon.fr

    Recruiting
  • Centre de recherche en nutrition humaine de Rhône-Alpes

    Pierre-Bénite, 69310

    Julie-Anne NAZARE, Julie-anne.nazare@univ-lyon1.fr

    Not yet recruiting
  • Hôpital Lyon sud, Endocrinology Diabetes Nutrition department

    Pierre-Bénite, 69310

    Berenice SEGRESTIN, +33 4 78 86 44 48, berenice.segrestin@chu-lyon.fr

    Not yet recruiting

Other trials in France

About this study

Official title: Randomised Controlled Trial Evaluating the Impact of a Pro-diversity Gut Microbiota Diet on Gut Microbiota, Eating Behaviour and Sensory Function in Patients Who Have Undergone Bariatric Surgery

Bariatric surgery is the most effective treatment for long-term weight loss and reducing obesity-related health risks. It alters the gastrointestinal tract as well as metabolic and hormonal functions, influencing eating behaviour. However, weight loss outcomes and long-term maintenance vary between patients, likely due to changes in the gut microbiota. Dietary recommendations aimed at improving microbiota diversity could help support sustained weight loss after surgery.

The BariaGut Taste study aims to compare two dietary approaches following bariatric surgery: nutritional counselling promoting gut microbiota diversity versus standard nutritional counselling. One year after surgery, the study will evaluate differences in microbiota diversity, changes in food preferences and eating behaviours, sensory profiles (taste, smell), levels of digestive and gut hormones fasting, before and after eating, cardiometabolic parameters, mental health, physical activity, and more, to better understand Bariatric surgery is the most effective treatment for long-term weight loss and reducing obesity-related health risks. It alters the gastrointestinal tract as well as metabolic and hormonal functions, influencing eating behaviour. However, weight loss outcomes and long-term maintenance vary between patients, likely due to changes in the gut microbiota. Dietary recommendations aimed at improving microbiota diversity could help support sustained weight loss after surgery.

Read more

The BariaGut Taste study aims to compare two dietary approaches following bariatric surgery: nutritional counselling promoting gut microbiota diversity versus standard nutritional counselling. One year after surgery, the study will evaluate differences in microbiota diversity, changes in food preferences and eating behaviours, sensory profiles (taste, smell), levels of digestive and gut hormones fasting, before and after eating, cardiometabolic parameters, mental health, physical activity, and more, to better understand the mechanisms that may explain variations in response to bariatric surgery.

The BariaGut Taste study is a prospective, randomized, controlled trial with two parallel groups, involving non-diabetic patients aged 25 to 65 y undergoing either sleeve gastrectomy or Roux-en-Y gastric bypass. The trial will be conducted at the digestive surgery department of Edouard Herriot Hospital, the endocrinology-diabetes-nutrition department of Lyon Sud Hospital Center, and the Human Nutrition Research Center Rhône-Alpes. 60 participants are expected to be recruited, with 30 in each arm.

Participants will be enrolled before surgery during a routine care visit with the surgeon. They will then undergo a metabolic assessment visit conducted exclusively for research purposes. This visit will allow to collect baseline data on primary outcomes via blood, expired air, and stool samples, anthropometric measurements, indirect calorimetry, a battery of questionnaires (TFEQ-21, DEBQ, PHQ-9, SF36, GSES, PANAS, ESUL, BES, DERS, GAD-7, IPAQ, BAQ, GSRS, sensory alterations, Bristol and Likert scales, and FNS), computerized food preference tests (LFPQ), and a standardized, video-recorded ad libitum buffet.

Participants will be followed up at 3, 6, and 12 months after surgery through visits combining clinical care and research assessments. The dietary interventions specific to each group will be provided since the 3-month visit. The assessments conducted before surgery will be repeated at 6 and 12 months, also integrating clinical care objectives.

Additional blood, stool, and adipose tissue samples collected during surgery will be stored to create a biobank.

Being tested
Nutritional counseling
Keywords
Bariatric surgery, gut microbiota, sensory alteration, food preferences, weight loss maintenance
Medical subject headings
Obesity, Food Preferences

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Nutritional counselingOther

    Nutritional counseling

Study groups in NCT07268508
Study groupRoleWhat they receive
Participants with nutritional counselling promoting gut microbiota diversityExperimentalGiven the low amounts of food consumed during the first months after surgery, the specific nutritional recommendations for this group will be implemented starting 3 months post-surgery. Before 3 months, participants will receive the standard nutritional recommendations of routine care after bariatric surgery, identical to those given to the second group (see below). From 3 months onwards, participants will be encouraged to increase the consumption of certain specific foods known for their benefits on the gut microbiota, particularly for promoting gut bacterial diversity, in addition to maintaining protein intake and paying attention to food textures. Summary sheets will be provided to help recall the recommendations.
Receives: Other: Nutritional counseling
Participants with standard nutritional counsellingNo interventionThe nutritional recommendations given to participants in this group are those applied in routine care within the Endocrinology, Diabetes, and Nutrition (EDN) Department for patients who have undergone sleeve gastrectomy or gastric bypass (Roux-en-Y). These recommendations aim to maintain adequate protein intake and are adapted to the recent changes in their digestive tract (pureed then mashed food during the first postoperative month). During the first 6 months, patients' food intake is significantly below their nutritional needs. So it is important to pay close attention to hydration (away from meals) and macronutrient intake, especially proteins, as well as the progression of food texture and chewing.

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Microbiota diversity 12 months after surgery

    The change in the diversity of the microbiota (shot gun metagenomic analysis, counting the number of microbial genes), between before surgery and one year after surgery (delta) between the two dietary intervention groups.

    Measured: Primary outcome will be assessed three times : before the surgery, 6 and 12 months after

Secondary outcomes (99)
  1. Eating behaviour during a standardised, filmed and validated ad libitum buffet : Food intake

    energy intake, macro- and micronutrient intake The items chosen during the buffet from the 17 items that will be offered will be noted. The quantities in g and calories consumed of each item will be estimated from the weighing of the plates before and after the buffet, the contribution of each of the items to the energy intake will also be evaluated.

    Measured: Before the surgery and at 6 and 12 month after

  2. Eating behaviour during a standardised, filmed and validated ad libitum buffet: Nutritional quality

    Nutritional quality through analysis of the foods chosen and consumed Buffet items are classified (pre-defined classification) into seven groups based on their macronutrient content and energy density: starchy foods, meat and fish, fruits and vegetables, dairy products, sweet desserts, sauces, and sweetened beverages. They are also classified according to their fat, sugar, and protein content, and their energy density (4 groups).

    The quantities consumed in grams and as a percentage of energy intake per group will be assessed for each subject and per visit.

    Measured: Before the surgery and at 6 and 12 month after

  3. Eating behaviour during a standardised, filmed and validated ad libitum buffet: Meal microstructure

    time spent selecting food at the buffet, duration of ingestion, ingestion speed, total meal duration, number of bites per minute, total number of bites and bites by food type, and food choices

    Several indicators will be assessed for the buffet's microstructure based on the analysis of videos taken during the buffet:

    • Buffet time

    Measured: Before the surgery and at 6 and 12 month after

  4. Eating behaviour during a standardised, filmed and validated ad libitum buffet: Meal appreciation

    time spent selecting food at the buffet, duration of ingestion, ingestion speed, total meal duration, number of bites per minute, total number of bites and bites by food type, and food choices Assessed with visual analog scale from 1(worse outcome) to 10 (better outcome)

    Measured: Before the surgery and at 6 and 12 month after

  5. Eating behaviour and preferences : Behaviors

    binge eating using sub-scores from tthe BES (Binge Eating Scale) for binge eating

    BES : Binge Eating Scale - score from 0 to 46, score of 46 = highest level of binge eating disorder

    Measured: Before the surgery and at 6 and 12 month after

  6. Eating behaviour and preferences : Food preferences

    Food preferences using the short version of the LFPQ (Leeds Food Preference Questionnaire) LFPQ : Leeds Food and Preference Questionnaire- score from 0 to 100 on preference or motivation for a type of food, high score = strong preference or motivation

    Measured: Before the surgery and at 6 and 12 month after

  7. Appetite : hunger level

    Assessed using visual analog scales rated from 0 (worse outcome) to 10 (better outcome) on the following dimensions : hunger

    Measured: Before the surgery and at 6 and 12 month after

  8. Appetite : satiety

    Assessed using visual analog scales rated rom 0 (worse outcome) to 10 (better outcome) on the following dimensions : feeling of satiety

    Measured: Before the surgery and at 6 and 12 month after

  9. Appetite : desire to eat

    Assessed using visual analog scales rated from 0 (worse outcome) to 10 (better outcome) on the following dimensions : desire to eat

    Measured: Before the surgery and at 6 and 12 month after

  10. Appetite : prospective consumption

    Assessed using visual analog scales rated from 0 (worse outcome) to 10 (better outcome) on the following dimensions : consommation

    Measured: Before the surgery and at 6 and 12 month after

  11. Appetite : meal appreciation

    Assessed using visual analog scales rated rom 0 (worse outcome) to 10 (better outcome) on the following dimensions : meal appreciation

    Measured: Before the surgery and at 6 and 12 month after

  12. Sensory functions : detection scores

    Assessed using Taste Strips tests

    Measured: Before the surgery and at 6 and 12 month after

  13. Sensory functions : intensity

    Assessed using Taste Strips tests

    Measured: Before the surgery and at 6 and 12 month after

  14. Sensory functions : pleasantness

    Assessed using Taste Strips tests

    Measured: Before the surgery and at 6 and 12 month after

  15. Sensory functions : edibility of tastes

    Assessed using Taste Strips tests

    Measured: Before the surgery and at 6 and 12 month after

  16. Sensory functions : edibility of odors

    Assessed using Taste Strips tests

    Measured: Before the surgery and at 6 and 12 month after

  17. Self-reported alterations in sensory functions

    Assessed using dedicated questions

    Measured: Before the surgery and at 6 and 12 month after

  18. Body perception

    Assessed using the BAQ questionnaire (Body Awareness Questionnaire) BAQ : Body Awarness Questionnaire - score from 13 to 65, score of 65 = positive assessment of one's body

    Measured: Before the surgery and at 6 and 12 month after

  19. Appetite : desire to eat

    Assessed using visual analog scales rated from 0 to 10 on the following dimensions: desire to eat

    Measured: Before the surgery and at 6 and 12 month after

  20. Appetite : prospective consumption

    Assessed using visual analog scales rated from 0 to 10 on the following dimensions

    Measured: Before the surgery and at 6 and 12 month after

  21. Microbiota composition

    Evaluated via gene function analysis from metagenomics data, metabolomics and short-chain fatty acid quantification

    Measured: Before the surgery and at 6 and 12 month after

  22. Microbiota function

    Evaluated via gene function analysis from metagenomics data, metabolomics and short-chain fatty acid quantification

    Measured: Before the surgery and at 6 and 12 month after

  23. Endocrine, digestive or intestinal hormones

    Blood sample to measure :

    Adiponectin µg/ml

    Measured: Before the surgery and at 6 and 12 month after Fasting (all except acylated ghrelin), before the buffet and 1 hour after (adiponectin, total GLP1, ghrelin, acylated ghrelin, total PYY, glucagon, GIP and FGF-19)

  24. Exhaled gas profiles

    Assessed by volatolomic signatures

    Measured: Before the surgery and at 6 and 12 month after

  25. Cardio-metabolic profile parameters

    BMI will be assessed

    Measured: Before the surgery and at 6 and 12 month after

  26. Cardio-metabolic profile parameters

    Energy metabolism by indirect calorimetry

    Measured: Before the surgery and at 6 and 12 month after

  27. Cardio-metabolic profile parameters

    postprandial plasma markers: We will assess: glycaemia (g/L)

    Measured: Before the surgery and at 6 and 12 month after

  28. Cardio-metabolic profile parameters

    CRP

    Measured: Before the surgery and at 6 and 12 month after

  29. Vital parameters

    Blood pressure

    Measured: Before the surgery and at 6 and 12 month after

  30. Nutritional status: Blood vitamin

    Blood vitamin status :

    For the research, we will focus only whether or not the participant has a deficiency in one of the vitamins measured (yes/no variable).

    The vitamins assessed are :

    • Vitamin B12 (pmol/L) should be above 145 pmol/L

    Measured: Before the surgery and at 6 (except plasma fatty acid profile) and 12 month after

  31. Nutritional status : Blood mineral

    Blood mineral status:

    • Calcium (mmol/L) should be above 64 mmol/L
    • Phosphor (mmol/L) should be above 0.81 mmol/L
    • Magnesium (mmol/L) should be above 0.66 mmol/L
    • Sodium (mmol/L) should be above 136 mmol/L
    • Potassium (mmol/L) should be above 3.4 mmol/L
    • Chlore (mmol/L) should be above 98 mmol/L

    Measured: Before the surgery and at 6 (except plasma fatty acid profile) and 12 month after

  32. Nutritional status : Plasma fatty acid

    Plasma fatty acid profile

    Measured: Before the surgery and at 6 (except plasma fatty acid profile) and 12 month after

  33. Nutritional status : Protein

    Protein status

    Measured: Before the surgery and at 6 (except plasma fatty acid profile) and 12 month after

  34. Average energy

    Assessed using 3-day dietary recall randomly selected from the 7 days preceding the visits

    Measured: Before the surgery and at 6 and 12 month after

  35. macronutrients intakes and proportions

    Assessed using 3-day dietary recall randomly selected from the 7 days preceding the visits

    Measured: Before the surgery and at 6 and 12 month after

  36. micronutrients intakes and proportions

    Assessed using 3-day dietary recall randomly selected from the 7 days preceding the visits

    Measured: Before the surgery and at 6 and 12 month after

  37. Mental health: Quality of life

    Quality of life using the SF36 questionnaire SF36 - health status questionnaire - score from 0 to 100, score of 100 = excellent perceived health

    Measured: Before the surgery and at 6 and 12 month after

  38. Mental health: Self-confidence

    Self-confidence and self-efficacy using the GSES GSES: Generalized Self-Efficacy Scale - score of 10 to 40, score of 40 = strong confidence in one's ability to effectively manage different life situations and challenges

    Measured: Before the surgery and at 6 and 12 month after

  39. Mental health: Depression

    Depression with PHQ-9 PHQ-9: Patient Health Questionnaire

    -score from 0 to 27, score of 27=severe depression

    Measured: Before the surgery and at 6 and 12 month after

  40. Mental health: Anxiety

    Anxiety assessment using GAD-7 GAD-7: Generalized Anxiety Disorder - if score >7 then anxiety disorders should be suspected

    Measured: Before the surgery and at 6 and 12 month after

  41. Physical activity

    Assessed using the short version of the IPAQ IPAQ: International Physical Activity Questionnaire - continuous daily energy expenditure score, high score means high AP

    The questionnaire allows the subject to be classified according to 3 levels of activity: inactive, moderate, high.

    Measured: Before the surgery and at 6 and 12 month after

  42. Emotions: positive and negative

    positive and negative emotion assessed using the PANAS scale PANAS: Positive Affectivity and Negative Affectivity Scale - 2 scores from 10 to 50 - positive affectivity score = 50 best, negative affectivity score = 50 worst

    Measured: Before the surgery and at 6 and 12 month after

  43. Emotions: food phobias

    food phobias using the FNS questionnaire FNS : Food Neophobia Scale -score from 10 to 70 - score of 70 = neophobia, i.e. less willingness to try new foods

    Measured: Before the surgery and at 6 and 12 month after

  44. Emotions: loneliness

    loneliness using the ESUL questionnaire University of Laval Loneliness Scale - score from 20 to 80, score of 80 = most pronounced feeling of loneliness

    Measured: Before the surgery and at 6 and 12 month after

  45. Changes in stool consistency

    Assessed using Bristol stool scale Bristol scale : 7 types of stools to choose from photo: type 1 = hard and lumpy stools, type 7 = completely liquid stools

    Measured: Before the surgery and at 6 and 12 month after

  46. Changes in stool frequency

    Assessed using Bristol stool scale : 7 types of stools to choose from photo: type 1 = hard and lumpy stools, type 7 = completely liquid stools

    Measured: Before the surgery and at 6 and 12 month after

  47. Changes in gastrointestinal symptoms

    Assessed using Bristol stool scale

    Measured: Before the surgery and at 6 and 12 month after

  48. Grade of hepatic steatosis

    Evaluation by FibroScan® but only for patients who had a FibroScan® performed before surgery.

    Measured: Before the surgery and at 12 month after

  49. Grade of hepatic fibrosis

    Evaluation by FibroScan® but only for patients who had a FibroScan® performed before surgery.

    Measured: Before the surgery and at 12 month after

  50. Eating behaviour and preferences : Behaviors

    Behaviors (emotional eating and cognitive restraint) using score from the DEBQ (Dutch Eating Behavior Questionnaire) a DEBQ : Dutch Eating Behaviour Questionnaire : 3 sub-scores: cognitive restriction, reactivity to external stimuli and emotionality from 1 to 5, score 5 = strong impact of eating behavior

    Measured: Before the surgery and at 6 and 12 month after

  51. Hepatic metabolic flexibility

    Assessed via the degree of alteration of MAMs (Mitochondia-Associated Membranes) in peripheral blood mononuclear cells (PBMCs), only for patients who had a FibroScan® performed before surgery.

    Measured: Before the surgery and at 6 and 12 month after

  52. Safety parameters

    thyroid function: Thyroid function is assessed based on TSH levels in mIU/L (should be above 0.4 mIU/L and below 4.8 mIU/L), 2.

    The assessment for the research is whether the measures are within the limits or not (yes/no variable).

    Measured: Before the surgery and at 6 and 12 month after

  53. Compliance and follow-up of advice given during the intervention

    Based on the three 24-hour reminders completed by participants before each visit, the dietitian will classify participants into three categories: good, average or poor compliance.

    Measured: until month 12

  54. Eating behaviour during a standardised, filmed and validated ad libitum buffet: Meal microstructure

    time spent selecting food at the buffet

    Measured: Before the surgery and at 6 and 12 month after

  55. Eating behaviour during a standardised, filmed and validated ad libitum buffet: Meal microstructure

    duration of ingestion

    Measured: Before the surgery and at 6 and 12 month after

  56. Eating behaviour during a standardised, filmed and validated ad libitum buffet: Meal microstructure

    ingestion speed

    Measured: Before the surgery and at 6 and 12 month after

  57. Changes in stool consistency

    Assessed using Likert scale Likert scale : 7 types of stools to choose from photo: type 1 = hard and lumpy stools, type 7 = completely liquid stools

    Measured: Before the surgery and at 6 and 12 month after

  58. Changes in stool consistency

    Assessed using gastrointestinal symptoms using GSRS Gastrointestinal Symptom Questionnaire - score 15 to 105, score 105=severe gastrointestinal symptoms

    Measured: Before the surgery and at 6 and 12 month after

  59. Safety parameters

    complete blood count

    Measured: Before the surgery and at 6 and 12 month after

  60. Safety parameters

    AST

    Measured: Before the surgery and at 6 and 12 month after

  61. Safety parameters

    ALT

    Measured: Before the surgery and at 6 and 12 month after

  62. Safety parameters

    gamma GT

    Measured: Before the surgery and at 6 and 12 month after

  63. Safety parameters

    bilirubin

    Measured: Before the surgery and at 6 and 12 month after

  64. Safety parameters

    alkaline phosphate

    Measured: Before the surgery and at 6 and 12 month after

  65. Safety parameters

    creatinine

    Measured: Before the surgery and at 6 and 12 month after

  66. Safety parameters

    uric acid

    Measured: Before the surgery and at 6 and 12 month after

  67. Safety parameters

    ionogram results: Sodium (mmol/L) which should be between 136 and 145 Potassium (mmol/L) which should be between 3.4 and 4.5 Chlorine (mmol/L) which should be between 98 and 107 Bicarbonates (mmol/L) which should be between 22 and 29

    Measured: Before the surgery and at 6 and 12 month after

  68. Safety parameters

    coagulation : prothrombin time

    Measured: Before the surgery and at 6 and 12 month after

  69. Changes in stool frequency

    Assessed using Likert scale

    Measured: Before the surgery and at 6 and 12 month after

  70. Changes in stool frequency

    Assessed using gastrointestinal symptoms using GSRS : 15 questions with answers from No discomfort at all at Very severe discomfort (7 levels)

    Measured: Before the surgery and at 6 and 12 month after

  71. Changes in gastrointestinal symptoms

    Assessed using Likert scale

    Measured: Before the surgery and at 6 and 12 month after

  72. Changes in gastrointestinal symptoms

    gastrointestinal symptoms using GSRS

    Measured: Before the surgery and at 6 and 12 month after

  73. Eating behaviour during a standardised, filmed and validated ad libitum buffet: Meal microstructure

    total meal duration

    Measured: Before the surgery and at 6 and 12 month after

  74. Eating behaviour during a standardised, filmed and validated ad libitum buffet: Meal microstructure

    number of bites per minute

    Measured: Before the surgery and at 6 and 12 month after

  75. Eating behaviour during a standardised, filmed and validated ad libitum buffet: Meal microstructure

    total number of bites

    Measured: Before the surgery and at 6 and 12 month after

  76. Eating behaviour during a standardised, filmed and validated ad libitum buffet: Meal microstructure

    bites by food type

    Measured: Before the surgery and at 6 and 12 month after

  77. Eating behaviour during a standardised, filmed and validated ad libitum buffet: Meal microstructure

    food choices

    Measured: Before the surgery and at 6 and 12 month after

  78. Eating behaviour during a standardised, filmed and validated ad libitum buffet: Meal microstructure

    Calorie intake consumed per minute of the buffet

    Measured: Before the surgery and at 6 and 12 month after

  79. Safety parameters

    ionogram results:

    Anion gap = (Na+ + K+) - (HCO3- + Cl-) (mmol/L) which should be between 12 and 20

    Measured: Before the surgery and at 6 and 12 month after

  80. Endocrine, digestive or intestinal hormones

    Blood sample to measure :

    Ghrelin pg/ml acylated ghrelin pg/ml

    Measured: Before the surgery and at 6 and 12 month after Fasting (all except acylated ghrelin), before the buffet and 1 hour after (adiponectin, total GLP1, ghrelin, acylated ghrelin, total PYY, glucagon, GIP and FGF-19)

  81. Endocrine, digestive or intestinal hormones

    Blood sample to measure :

    GIP pmol/l total GLP-1 : pmol/L glucagon : pmol/L

    Measured: Before the surgery and at 6 and 12 month after Fasting (all except acylated ghrelin), before the buffet and 1 hour after (adiponectin, total GLP1, ghrelin, acylated ghrelin, total PYY, glucagon, GIP and FGF-19)

  82. Endocrine, digestive or intestinal hormones

    Blood sample to measure :

    total PYY : ng/L

    Measured: Before the surgery and at 6 and 12 month after Fasting (all except acylated ghrelin), before the buffet and 1 hour after (adiponectin, total GLP1, ghrelin, acylated ghrelin, total PYY, glucagon, GIP and FGF-19)

  83. Endocrine, digestive or intestinal hormones

    Blood sample to measure :

    leptin : ng/ml

    Measured: Before the surgery and at 6 and 12 month after Fasting (all except acylated ghrelin), before the buffet and 1 hour after (adiponectin, total GLP1, ghrelin, acylated ghrelin, total PYY, glucagon, GIP and FGF-19)

  84. Cardio-metabolic profile parameters

    We will assess: insulin (mU/L)

    Measured: Before the surgery and at 6 and 12 month after

  85. Cardio-metabolic profile parameters

    We will assess: triglycerides (mmol/L), HDL (mmol/L), LDL (mmol/L), ApoB (mmol/L), sphingolipid (mmol/L) and unesterified fatty acid(mmol/L)

    Measured: Before the surgery and at 6 and 12 month after

  86. Cardio-metabolic profile parameters

    we will calculate: HOMA-IR (=insulin*glycarmia/22.5) and the total cholesterol/HDL cholesterol ratio.

    Measured: Before the surgery and at 6 and 12 month after

  87. Cardio-metabolic profile parameters

    postprandial plasma markers: We will assess: insulin (mU/L)

    Measured: Before the surgery and at 6 and 12 month after

  88. Nutritional status: Blood vitamin

    Blood vitamin status :

    For the research, we will focus only whether or not the participant has a deficiency in one of the vitamins measured (yes/no variable).

    The vitamins assessed are :

    • Vitamin B9 (mmol/L) should be above 10.4 mmol/L

    Measured: Before the surgery and at 6 (except plasma fatty acid profile) and 12 month after

  89. Nutritional status: Blood vitamin

    Blood vitamin status :

    For the research, we will focus only whether or not the participant has a deficiency in one of the vitamins measured (yes/no variable).

    The vitamins assessed are :

    • Vitamin B1 (nmol/L) should be above 78 nmol/L

    Measured: Before the surgery and at 6 (except plasma fatty acid profile) and 12 month after

  90. Nutritional status: Blood vitamin

    Blood vitamin status :

    For the research, we will focus only whether or not the participant has a deficiency in one of the vitamins measured (yes/no variable).

    The vitamins assessed are :

    • Vitamin C (µmol/L) should be above 25 µmol/L
    • Vitamin A (µmol/L) should be above 1.40 µmol/L

    Measured: Before the surgery and at 6 (except plasma fatty acid profile) and 12 month after

  91. Nutritional status : Blood mineral

    Blood mineral status:

    • Iron (µmol/L) should be above 5.8µmol/L
    • Selenium (µmol/L) should be above 56µmol/L
    • Zinc (µmol/L) should be above 9.20µmol/L

    Measured: Before the surgery and at 6 (except plasma fatty acid profile) and 12 month after

  92. Safety parameters

    thyroid function: Thyroid function is assessed based on free thyroxine in pmol/L (should be above 11.9 pmol/L and below 21.9 pmol/L)

    The assessment for the research is whether the measures are within the limits or not (yes/no variable).

    Measured: Before the surgery and at 6 and 12 month after

  93. Safety parameters

    thyroid function: Thyroid function is assessed based on free triiodothyronine in pmol/L (should be above 3.1 pmol/L and below 6.8 pmol/L).

    The assessment for the research is whether the three measures are within the limits or not (yes/no variable).

    Measured: Before the surgery and at 6 and 12 month after

  94. Cardio-metabolic profile parameters

    Waist-to-hip ratio will be assessed

    Measured: Before the surgery and at 6 and 12 month after

  95. Vital parameters

    resting heart rate

    Measured: Before the surgery and at 6 and 12 month after

  96. Safety parameters

    coagulation : activated partial thromboplastin time

    Measured: Before the surgery and at 6 and 12 month after

  97. Safety parameters

    coagulation : fibrinogen

    Measured: Before the surgery and at 6 and 12 month after

  98. Cardio-metabolic profile parameters

    We will assess: total cholesterol (g/L)

    Measured: Before the surgery and at 6 and 12 month after

  99. Cardio-metabolic profile parameters

    We will assess: HbA1c (mmol/mol),

    Measured: Before the surgery and at 6 and 12 month after

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted5 Dec 2025
  2. Study start5 Nov 2025
  3. Primary completion5 Nov 2027 (estimated)
  4. Study completion5 Apr 2029 (estimated)

Resources

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
Parallel groups
Model description
* Arm with nutritional counselling promoting gut microbiota diversity * Arm with standard nutritional counselling
Masking
Single blind
Who is masked
Participant
Enrolment
60 participants (estimated)
IDs, dates and publications
ClinicalTrials.gov ID
NCT07268508
Sponsor's protocol ID
69HCL24_0033
Acronym
BariaGut Taste
Status last verified
Apr 2026
First submitted
14 Aug 2025
Last updated
3 Apr 2026
Results posted
No
Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No

Questions about this trial

What is this clinical trial studying?

A study testing Nutritional counseling in people with Obesity (Disorder) and Bariatric Surgery, run by Hospices Civils de Lyon at 3 sites in France.

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 6 inclusion and 14 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 3 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 3 sites in France. 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 Julie-Anne NAZARE (+33 6 88 87 09 62, julie-anne.nazare@univ-lyon1.fr), or a site near the patient. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Microbiota diversity 12 months after surgery (time frame: Primary outcome will be assessed three times : before the surgery, 6 and 12 months after). 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 3 Apr 2026.

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