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Effectiveness of a Modified Cost-Effective Dietary Plan in Promoting Weight Loss and Preservation of Lean Body Mass in Patients After Bariatric Surgery

Effectiveness of a Modified Cost-Effective Dietary Plan in Promoting Weight Loss and Preservation of Lean Body Mass in Patients After Bariatric Surgery

Status
Not yet recruiting
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT07111767
Enrollment
122
Registered
2025-08-08
Start date
2025-10-31
Completion date
2026-06-30
Last updated
2025-08-08

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Bariatric Surgery, Body Composition, Nutritional Status, Obesity

Keywords

Bariatric surgery, Obesity management, Post-bariatric diet, Cost-effective diet, Low-cost diet plan, Vitamin B12 deficiency, Iron deficiency, Vitamin D deficiency, Weight loss after bariatric surgery, Lean body mass preservation

Brief summary

This study will see if a low-cost dietary plan, based on the standard dietary guidelines of the American Society for Metabolic and Bariatric Surgery (ASMBS) and using locally available foods, can help patients lose weight and keep their lean body mass after bariatric surgery. It will also check if this plan can maintain healthy levels of important nutrients such as vitamin B12, iron, and vitamin D. Patients who have undergone bariatric surgery will be randomly assigned to follow either the low-cost diet or the regular hospital diet. Their weight, body composition, and nutrient levels will be tracked at baseline, and at 1, 3, and 6 months after surgery. The aim is to find out if this simpler, affordable diet, which follows international standards, works as well as the regular plan while being easier for low-income patients to follow.

Detailed description

Obesity is a growing global health problem and is recognized by the World Health Organization (WHO) as a leading cause of preventable disease. It is a complex, long-term condition influenced by multiple factors, and treatment options range from lifestyle changes to medications and surgery. Bariatric surgery is currently the most effective long-term treatment for morbid obesity. It not only helps in significant weight loss but also improves obesity-related health problems such as type II diabetes, hypertension, and obstructive sleep apnea, while improving quality of life. Among the various surgical techniques, Roux-en-Y gastric bypass (RYGB), sleeve gastrectomy (SG), and one-anastomosis gastric bypass (OAGB/MGB) are the most commonly performed. However, these surgeries can lead to reduced absorption of essential nutrients because they bypass parts of the intestine where vitamins and minerals are absorbed. Nutrient deficiencies, particularly in vitamin B12, iron, and vitamin D, are common after bariatric surgery. Therefore, structured dietary management and supplementation are essential after surgery to prevent these deficiencies and preserve lean body mass (LBM). Standard dietary recommendations from the American Society for Metabolic and Bariatric Surgery (ASMBS) suggest a gradual progression from liquids to solid foods, adequate protein intake (1.0-1.5 g/kg), and lifelong use of vitamin and mineral supplements. However, in countries like Pakistan, where 45% of the population lives below the international poverty line, the standard postoperative diet often includes costly imported supplements like whey protein, which are unaffordable and hard to access for most patients, particularly those from rural areas. This creates barriers to dietary compliance and worsens clinical outcomes. Adequate protein intake plays a key role in preserving lean body mass and improving recovery after bariatric surgery. Nutritional deficiencies, particularly in vitamin B12, iron, and vitamin D, remain prevalent after bariatric surgery and require targeted nutritional strategies. In response to these challenges, this study introduces a low-cost dietary plan based on ASMBS guidelines using locally available, affordable foods to meet protein and micronutrient needs. It aims to compare this plan with the conventional high-cost hospital diet to determine whether it can effectively promote weight loss, maintain lean body mass, and prevent micronutrient deficiencies. By aligning with international standards while addressing local socioeconomic constraints, this approach could improve patient adherence, nutritional outcomes, and overall recovery following bariatric surgery.

Interventions

DIETARY_SUPPLEMENTLow-Cost Post-Bariatric Diet

Low-Cost Post-Bariatric Diet (Experimental): Based on the American Society for Metabolic and Bariatric Surgery (ASMBS) guidelines. Uses affordable, locally available foods (e.g., eggs, lentils, local dairy products) to meet protein and micronutrient needs. Designed to be cost-effective and accessible for patients from low-income or rural areas.

DIETARY_SUPPLEMENTStandard High-cost Post-Bariatric Diet

Standard Post-Bariatric Diet (Active Comparator): The conventional high-cost diet currently followed at the study hospital. Includes imported or expensive protein supplements such as whey protein and cottage cheese, along with nutritional products not easily accessible in rural or low-resource settings.

Sponsors

Khyber Teaching Hospital
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
No

Inclusion criteria

* Able to give informed written consent * Adults between the ages of 18 and 65 undergoing primary bariatric surgery (Roux-en-Y gastric bypass, sleeve gastrectomy, or OAGB)

Exclusion criteria

* Patients having revision bariatric surgery * Patients with recognized diseases related to micronutrient supplementation * Patients with pre-existing gastrointestinal, metabolic, or endocrine disorders that impair nutrient absorption

Design outcomes

Primary

MeasureTime frameDescription
Weight LossBaseline, 1 month, 3 months, and 6 months after surgery.Weight loss will be measured using a calibrated digital weighing scale.Weight loss will be defined as the reduction in body weight (kg) from baseline. Unit of Measure: Kilograms (kg)

Secondary

MeasureTime frameDescription
Change in Serum Iron LevelsBaseline, 1 month, 3 months, and 6 months post-surgery.Hemoglobin (g/dL) and serum ferritin (ng/mL) measured via blood tests.Iron deficiency will be defined as Hb \<12 g/dL (women) or \<13 g/dL (men) and/or ferritin \<15 ng/mL.
Change in Serum Vitamin B12 LevelsBaseline, 1 month, 3 months, and 6 months post-surgery.Measured via serum vitamin B12 assay.Levels below 200 pg/mL will be considered deficient.
Change in Serum Vitamin D LevelsBaseline, 1 months, 3 months, and 6 months post-surgery.Serum 25(OH) vitamin D (ng/mL) measured via blood assay . Levels below 20 ng/mL will be considered deficient.
Lean Body Mass (LBM)Baseline, 1 month, 3 months, and 6 months postoperativelyChange in lean body mass assessed using bioelectrical impedance analysis to evaluate preservation of lean tissue after bariatric surgery. Unit of Measure: Kilograms (kg)
Body Mass Index (BMI)Baseline, 1 month, 3 months, and 6 months postoperativelyBMI will be calculated by dividing weight (kg) by height squared (m²). Height will be measured only at baseline, as it remains unchanged postoperatively. Follow-up BMI will be derived using baseline height and follow-up weight measurements.Unit of Measure: kg/m²

Countries

Pakistan

Contacts

Primary ContactSafina Tanveer, MBBS,FCPS-II training
safina.tanveer@kth.edu.pk0092 337 6919129

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026