This is an open-label, four-arm, randomized, controlled clinical study designed to evaluate the efficacy and safety of a structured Weight Management Program (WMP) in overweight and obese adults with a body mass index (BMI) ≥ 23 kg/m² (Asian Indian ethnicity cut-off). A total of 140 subjects will be enrolled and randomized equally into four arms: one control arm and three intervention arms with varying levels of nutritional intervention.

The Weight Management Program comprises three sequential phases: a pre-engagement gut-reset phase (10 days), an intensive intervention phase (30 days), and a maintenance phase (60 days). The intervention arms will receive combinations of meal replacements, protein supplements, fiber supplements, probiotics, and multivitamin-multimineral supplements, along with nutritional and behavioral counseling, calorie-deficit diet plans, and prescribed physical activity. The control arm will follow a free-living lifestyle without intervention.

The primary efficacy outcome is the proportion of subjects demonstrating a reduction in body weight and/or BMI from baseline to the end of the intensive phase. Secondary outcomes include changes in body weight and BMI at the end of the maintenance phase, maintenance of weight loss, changes in body composition, waist circumference, waist-hip ratio, lipid profile, metabolic parameters, physical activity, quality of life, and safety outcomes including adverse events.

The study aims to generate evidence on the effectiveness and safety of a holistic, lifestyle-based weight management program incorporating nutritional supplementation, dietary modification, physical activity, and behavioral support in overweight and obese individuals.

Inclusion Criteria:

• - Male and female subjects age between 20 to 45 years
• Non-pregnant and non-lactating
• Body Mass Index (kg/m2)- ≥ 23 (considered overweight/obese as per the ethnicity cut off values for Asian Indians)
• Following stable eating habits
• Not on any medication that can affect Lipid profile, body composition or weight
• Nonalcoholic and non- smoker
• Subjects who are willing to sign the informed consent and comply with study requirement of meal replacements strictly
• Women in the reproductive age group- should be agreeing to follow standard contraceptive measures
• Individuals who are seriously motivated to lose weight and willing to be part of any one of the interventions where Protein drink with buttermilk, skimmed milk or water OR 1 Meal replacement OR 2 Meal replacement would be given.

Exclusion Criteria:

• - On medication/ HRT (Hormone Replacement Therapy)
• Suffering from endocrine hypothalamic- pituitary disease, women with PCOS, adrenal disorder, hypothyroidism,
• Subjects with Diabetes type 1 or 2 to be excluded
• Women in the reproductive age group not willing to use standard contraceptive measures.
• Other conditions like CKD, stones, liver dysfunction (with elevated enzyme levels), history of cancer, eating disorders, chronic gastrointestinal disorders (IBD or celiac), metabolic disorders like hypertension, CVDs- that might impair the outcomes
• Malignancy which is currently active or in remission for less than five years after last treatment
• Unstable weight (± 5 % fluctuation in their body weight for past 8-weeks at study entry)
• Have undergone gastroplasty or weight reducing surgery
• Subjects who have participated in another clinical study within the past 30 days prior to screening or are likely to simultaneously participate in another clinical study.
• Practicing any structured commercial weight management program/ intermittent fasting or any diet regime in the last 30 days prior to screening.
• Patients who are doubtful to comply with study procedures for mental, psychological or social reasons.