Pharmacological therapy and dietary intervention for obesity management: A one-year prospective cohort study in Baghdad

Abstract

BACKGROUND:

Evidence directly comparing long-term pharmacological therapy and structured dietary intervention for obesity in Middle Eastern populations is limited. This study provides 12-month real-world comparative data from specialized obesity clinics in Baghdad, Iraq.

MATERIALS AND METHODS:

A prospective cohort study included 120 adults with obesity (BMI ≥30 kg/m²) from June 2024 to June 2025. Participants received either pharmacological therapy (orlistat 120 mg three times daily or liraglutide 3.0 mg/day; n = 60) with standard lifestyle advice, or intensive individualized dietary counseling by board-certified dietitians (n = 60). The primary outcome was percentage weight loss at 12 months. Secondary outcomes assessed body composition, metabolic parameters, physical activity, adherence, adverse effects, and quality of life. Between-group differences were analyzed using independent t-tests with exact P values and 95% confidence intervals.

RESULTS:

At 12 months, pharmacological therapy associated with greater early weight loss but reached a plateau (13.5 ± 3.7% vs. 11.3 ± 4.3%, P < 0.001; 95% CI: 1.1–2.8%). Dietary intervention associated with higher fat-mass loss (68.9% vs. 53.1%, P < 0.001), better lean-mass preservation (P = 0.003), and superior improvements in LDL-cholesterol (P = 0.012), fasting glucose (P = 0.047), systolic blood pressure (P = 0.041), and physical activity (P = 0.001). Adherence (73.3% vs. 58.3%, P = 0.038) and patient satisfaction (P < 0.001) were higher with diet, while gastrointestinal side effects were more common with pharmacotherapy (68.3% vs. 11.7%, P < 0.001).

CONCLUSIONS:

Intensive dietary counseling yielded to superior long-term metabolic, behavioral, and patient-centered outcomes with better adherence, supporting its use as a first-line obesity treatment. Pharmacological therapy may be an adjunct for selected patients, highlighting the importance of structured, dietitian-led lifestyle programs within health systems.

Introduction

Obesity has become a significant health issue, with over 650 million adults worldwide getting affected by it and leading to cardiovascular disease, type 2 diabetes, various cancers and premature death.[1] It remains one of the most critical public health challenges of the 21^st century.[2] It has increased almost three times since 1975, and low- and middle-income countries have witnessed the fastest increase.[3] In Iraq, obesity is reported to be at 30–38% among adults due to the high rate of urbanization, growing intake of westernized food, and the decreasing level of physical activities.[4]

The existing evidence-based interventions of obesity management involve lifestyle modification, pharmacotherapy, and bariatric surgery.[5] Despite anti-obesity drugs like liraglutide and orlistat causing weight loss of 5–15%, the international guidelines always recommend lifestyle change, specifically structured dietary intervention as the initial intervention.[6] Individualized diet plans that are energy-restricted usually lead to a 7–10% weight loss over 6–12 months, whereas Mediterranean and DASH-type patterns have additional cardiometabolic effects that are not directly linked to weight loss.[7] There is also strong evidence that maintaining a healthy lifestyle, which includes eating a balanced diet, losing a small amount of weight, and getting regular exercise, can lower the risk of type 2 DM complications and maintain healthy blood glucose levels.[8] Newer agents and GLP-1 receptor agonists have proven to be more effective in clinical trials, but their sustainability and availability over the long term are issues.[9]

There are still significant gaps in research. The majority of clinical trials evaluate short-term results (3–6 months), obesity requires life-long management with high chances of weight gain once the treatment is stopped.[10] Moreover, there is a potential of metabolic adaptation and decreasing adherence to restrict pharmacological effects durability.[11] There is little direct long-term comparison between pharmacological therapy and dietary counseling, particularly after six months.[12] Evidence from Middle Eastern populations is particularly limited, although they have varying cultural dietary habits, health-system limitations, and a high obesity burden.[13] Few studies reflect real-world clinical practice, in which patient adherence, cost, and sustainability have a strong effect on the outcome.

This study provides several novel contributions: (1) the study offers one of the longest follow-up durations (12 months) on obesity intervention comparisons in the Middle East region; (2) the research has includes comprehensive assessment of body composition, metabolic markers, behavioral outcomes, and patient-centered measures; (3) the study reflects real-world clinical practice patterns rather than idealized trial conditions; and (4) the study addresses a critical evidence gap in Iraqi and regional obesity management by directly comparing pharmacological therapy with intensive dietitian-led intervention in a pragmatic study design.

Figure 1 presents a conceptual model of the pathway of obesity management between the type of intervention and clinical outcomes.

Figure 1.

Conceptual model of the obesity management pathway

Materials and Methods

Study design and setting

This is prospective not randomization cohort study that conducted in Baghdad, Iraq, between June 2024 and June 2025. Two specialized obesity clinics participated: one delivering individualized dietary intervention and the other offered pharmacological interventions. The pragmatic design is reflected routine clinical practice, which enhancing external validity.

Study participants and sampling

The participants were adults between 18 and 60 years old with BMI 30 kg/m 2 and who were seeking treatment of obesity. The exclusion criteria were pregnancy or lactation, secondary obesity, severe psychiatric disorder, contraindication to anti-obesity drugs, previous bariatric surgery, and any organized weight-loss program in the last six months. The calculations of sample sizes showed that at least 48 individuals will be used in each group (power 80%, α = 0.05), assuming an expected 3% difference in percentage weight loss and SD of 4%. To account for attrition, 60 participants were enrolled in each group (total n = 120). Participants were consecutively recruited from both clinics.

Data collection tool and technique

Participants were assigned to treatment pathways based on the routine clinical workflow of each center.

Pharmacological group: The patients were assigned to either liraglutide (3.0 mg/day) or orlistat (120 mg three times daily), depending on the assessment of the physician, contraindications, preference of the patient and affordability. All patients also received standardized lifestyle advice on portion control, reducing high-fat and high-sugar foods, increasing intake of fruits and vegetables, whole grains, and completing ≥150 minutes/week of moderate physical activity. Clinic visits would be conducted monthly to monitor and adhere to.

Dietary intervention group: Individualized meal plans were provided by board-certified clinical dietitians with a 500–1000 kcal/day deficit. Plans were focused on culturally similar Iraqi foods, higher fiber intake, balanced macronutrients (45–55% carbohydrates, 20–30% protein, and 25–30% fat) and behavioral strategies including goal-setting, barrier identification, and self-monitoring. The visits were held every 2–4 weeks during the intensive phase (months 0–3) and once a month in the maintenance phase (months 4–12). The participants were received meal plans, food-exchange lists, and portion guides.

Outcome assessment: Standardized procedures were used to measure at baseline and 3, 6, 9, and 12 months:

• Anthropometrics: weight, BMI, waist circumference

• Body composition: bioelectrical impedance analysis (BIA); the device used has validated reproducibility in adult populations[14]

• Metabolic parameters: fasting glucose, HbA1c, lipid profile, blood pressure

• Physical activity: IPAQ–Short Form, a validated instrument[15]

• Quality of life: IWQOL-Lite, with established psychometric reliability[16]

• Adherence: ≥80% medication use or ≥5 days/week diet-plan adherence

• Side effects: structured symptom checklist

• Patient satisfaction: 5-point Likert scales

Validity and reliability of instruments

The validity and reliability of all measurement instruments are established. Bioelectrical impedance analyzer has confirmed the reproducibility in the adult population (intraclass correlation >0.95). The IPAQ-Short Form exhibits good test-retest reliability (ρ = 0.76) and acceptable criterion validity. The IWQOL-Lite has determined psychometric properties with Cronbach’s alpha >0.90 for total score and >0.80 for subscales.

Statistical analysis method

Analyses followed the intention-to-treat principle. Missing values were imputed using last observation carried forward. Baseline characteristics were compared using independent t-tests for continuous variables and Chi-square tests for categorical variables. Within-group changes were assessed using paired t-tests. Between-group comparisons of primary and secondary outcomes used independent t-tests with exact P values and 95% confidence intervals. Multivariate linear regression identified independent predictors of 12-month weight loss, including treatment type, adherence, baseline BMI, age, sex, physical activity change, and metabolic variables. Statistical significance was set at P < 0.05. Analyses were performed using SPSS version 26.0.

Results

Participant flow and characteristics

Of 134 adults screened, 120 met eligibility criteria and were enrolled (60 in each group). Fourteen participants (11.7%) were lost to follow-up over 12 months: 9 from the pharmacological group (15.0%) and 5 from the dietary group (8.3%, P = 0.25). Baseline characteristics were comparable between groups, with no differences in age, sex distribution, BMI, waist circumference, metabolic comorbidities, smoking, educational level, or baseline physical activity. [Table 1]

Table 1.

Baseline characteristics of study participants

Characteristic		Group A (Pharmacological) n=60		Group B (Dietary) n=60		P
Age (years), mean±SD		38.4±10.2		39.1±9.6		0.71
Female sex, n (%)		32 (53.8)		40 (67.1)		0.14
Weight (kg), mean±SD		94.8±15.3		93.2±16.1		0.58
BMI (kg/m²), mean±SD		34.8±3.9		34.5±4.2		0.68
Waist circumference (cm), mean±SD		107.4±11.2		106.8±12.5		0.79
Type 2 diabetes mellitus, n (%)		12 (20.0)		14 (23.3)		0.65
Hypertension, n (%)		18 (30.0)		21 (35.0)		0.56
Dyslipidemia, n (%)		24 (40.0)		22 (36.7)		0.71
Prediabetes (HbA1c 5.7-6.4%), n (%)		19 (31.7)		19 (31.7)		1.00
Current smoker, n (%)		14 (23.3)		11 (18.3)		0.50
Education level						0.62
Secondary or less, n (%)		22 (36.7)		19 (31.7)
University or higher, n (%)		38 (63.3)		41 (68.3)
Physical activity (IPAQ), n (%)						0.67
Low (<600 MET-min/week)		34 (56.7)		31 (51.7)
Moderate (600-3000 MET-min/week)		22 (36.7)		24 (40.0)
High (>3000 MET-min/week)		4 (6.7)		5 (8.3)

BMI: body mass index; HbA1c: glycated hemoglobin; IPAQ: International Physical Activity Questionnaire; MET: metabolic equivalent of task; SD: standard deviation

Weight loss outcomes

Both groups were found to substantially reduce weight in 12 months with the pharmacological group recording higher rates of early reduction and the dietary group recording gradual and progressive reduction. Mean percentage weight loss at age 12 months, with pharmacological versus dietary intervention was 13.5 ± 3.7% and 11.3 ± 4.3%, respectively (P = 0.001). Early weight loss was higher in the pharmacological group at 3 and 6 months, but thereafter there was a plateau, and dietary therapy continued to decline. In the pharmacological group, 73.3% of the participants had ≥ 10% weight loss compared to 58.3% in the control group (P = 0.007), and 91.7% of the participants had ≥ 5% weight loss versus 86.7% (P = 0.36). [Table 2]

Table 2.

Weight loss outcomes at 12 months

Outcome		Group A (Pharmacological) n=60		Group B (Dietary) n=60		Mean Difference (95% CI)		P
Weight at 12 months (kg), mean±SD		82.1±14.7		82.4±15.3		-0.3 (-5.9 to 5.3)		0.91
Absolute weight loss (kg), mean±SD		12.7±3.6		10.8±4.2		1.9 (0.5 to 3.3)		<0.001
Percentage weight loss (%), mean±SD		13.5±3.7		11.3±4.3		2.2 (0.8 to 3.6)		<0.001
Weight loss ≥5%, n (%)		55 (91.7)		52 (86.7)		5.0% (-5.8 to 15.8%)*		0.36
Weight loss ≥10%, n (%)		44 (73.3)		35 (58.3)		15.0% (-0.7 to 30.7%)*		0.007
Weight loss trajectory by time point
3 months (kg), mean±SD		4.2±1.8		3.1±1.5		1.1 (0.5 to 1.7)		0.001
6 months (kg), mean±SD		9.8±3.2		7.3±3.1		2.5 (1.4 to 3.6)		<0.001
9 months (kg), mean±SD		11.2±3.4		9.1±3.8		2.1 (0.7 to 3.5)		0.003
12 months (kg), mean±SD		12.7±3.6		10.8±4.2		1.9 (0.5 to 3.3)		<0.001
BMI at 12 months (kg/m²), mean±SD		30.2±3.8		30.4±4.1		-0.2 (-1.5 to 1.1)		0.79
BMI reduction (kg/m²), mean±SD		4.6±1.3		4.1±1.5		0.5 (-0.04 to 1.04)		0.08

*For proportions, the difference is presented as an absolute percentage difference with its 95% CI

Body composition changes

The body composition analysis revealed clinically significant differences. Dietary intervention was more effective in preserving lean mass (−2.6 ± 1.8% vs -6.3 ± 2.5% P = 0.003) and had a higher proportion of fat mass reduction relative to total weight loss (68.9% vs 53.1%, P < 0.001). Fat mass declined considerably in both groups, but the percentage change was larger in the dietary group (−18.7 ± 6.2% vs -15.2 ± 5.3% P = 0.04). Waist circumference declined comparably in both groups. [Table 3]

Table 3.

Body composition changes at 12 months

Parameter		Group A (Pharmacological) n=60		Group B (Dietary) n=60		Mean Difference (95% CI)		P
Fat mass change (kg), mean±SD		-6.7±2.8		-7.4±3.1		0.7 (-0.4 to 1.8)		0.21
Fat mass change (%), mean±SD		-15.2±5.3		-18.7±6.2		3.5 (1.0 to 6.0)		0.04
Proportion of weight loss as fat (%), mean±SD		53.1±12.4		68.9±11.7		-15.8 (-20.3 to -11.3)		<0.001
Lean mass change (kg), mean±SD		-6.0±2.4		-3.4±1.9		-2.6 (-3.3 to -1.9)		<0.001
Lean mass change (%), mean±SD		-6.3±2.5		-2.6±1.8		-3.7 (-4.6 to -2.8)		0.003
Body fat % change, mean±SD		-3.1±2.2		-4.8±2.6		1.7 (0.7 to 2.7)		0.006
Waist circumference change (cm), mean±SD		-9.8±4.2		-11.3±4.7		1.5 (-0.2 to 3.2)		0.08

The “Mean Difference” is calculated as (Group A - Group B). A negative value for “Lean mass change” and “Proportion... as fat” indicates a greater reduction/preservation in Group B

Metabolic parameter changes

Both groups showed meaningful metabolic improvements, though dietary group was associated with superior reductions in LDL-cholesterol (P = 0.012), fasting glucose (P = 0.047), and systolic blood pressure (P = 0.041). In those participants with prediabetes at the baseline (n = 38), normoglycemia at 12 months was achieved more frequently with dietary intervention (85.0% vs 52.6%, P = 0.048). Improvements in HDL-cholesterol, triglycerides, and diastolic blood pressure were comparable. [Table 4]

Table 4.

Metabolic parameter changes at 12 months

Parameter		Group A (Pharmacological) n=60		Group B (Dietary) n=60		Mean Difference (95% CI)		P
Fasting glucose change (mg/dL)		-7.1±7.2		-11.5±8.9		4.4 (0.05 to 8.75)		0.047
HbA1c change (%)		-0.4±0.5		-0.6±0.6		0.2 (-0.05 to 0.45)		0.12
Total cholesterol change (mg/dL)		-18.7±14.6		-26.3±17.8		7.6 (-0.05 to 15.25)		0.051
LDL-cholesterol change (mg/dL)		-13.1±12.7		-22.1±15.3		9.0 (1.6 to 16.4)		0.012
HDL-cholesterol change (mg/dL)		+5.2±4.6		+6.1±5.2		-0.9 (-2.7 to 0.9)		0.52
Triglycerides change (mg/dL)		-28.4±22.7		-34.6±26.3		6.2 (-3.1 to 15.5)		0.33
Systolic BP change (mmHg)		-7.2±6.5		-10.4±7.8		3.2 (0.1 to 6.3)		0.041
Diastolic BP change (mmHg)		-4.8±5.3		-6.2±6.1		1.4 (-0.8 to 3.6)		0.28

HbA1c: glycated hemoglobin; HDL: high-density lipoprotein; LDL: low-density lipoprotein; SD: standard deviation

Physical activity changes

Both groups showed significantly increased physical activity, but the dietary group showed a markedly greater improvement. The increase in mean MET-minutes/week by 89% in the dietary group compared with 47% in the pharmacological group (P = 0.001). At 12 months, 27.1% of participants in the dietary group achieved high activity levels (>3000 MET-min/week) compared with 13.7% in the pharmacological group (P = 0.035).

Treatment adherence and adverse effects

Compliance was also much higher in the dietary group at 12 months (73.3% vs 58.3% P = 0.038). The adherence to the medication declined over time, especially after month 6, and 20% of pharmacological participants discontinuing medication entirely. Adverse effects were notably more frequent in the pharmacological group, especially gastrointestinal symptoms such as diarrhea, oily stools, flatulence, and abdominal cramping (all P < 0.001). Injection-site reactions occurred only among liraglutide users. [Table 5]

Table 5.

Adverse effects during 12-month study period

Adverse Effect		Group A (Pharmacological) n (%)		Group B (Dietary) n (%)		P
Any gastrointestinal symptom		41 (68.3)		7 (11.7)		<0.001
Diarrhea		32 (53.3)		4 (6.7)		<0.001
Flatulence		28 (46.7)		5 (8.3)		<0.001
Oily/fatty stools		24 (40.0)		2 (3.3)		<0.001
Abdominal pain/cramping		19 (31.7)		3 (5.0)		<0.001
Fecal urgency		16 (26.7)		2 (3.3)		<0.001
Headache		16 (26.7)		8 (13.3)		0.009
Nausea		12 (20.0)		6 (10.0)		0.12
Injection site reactions†		7 (18.3)		0 (0.0)		0.006
Constipation		6 (10.0)		4 (6.7)		0.51
Fatigue		9 (15.0)		11 (18.3)		0.62
Dizziness		5 (8.3)		3 (5.0)		0.46
Hypoglycemia (mild)		3 (5.0)		2 (3.3)		0.65
Severity classification
Mild (no interference with activities)		28 (46.7)		6 (10.0)		<0.001
Moderate (some interference)		13 (21.7)		1 (1.7)		<0.001
Severe (significant interference)		0 (0.0)		0 (0.0)		-

Among liraglutide users only (n=38 in Group A)

Patient-centered outcomes

Dietary intervention generated higher satisfaction scores across all domains, including perceived control, long-term confidence, and support received (all P < 0.001). Quality of life improved in both groups, with significantly greater gains in the dietary group as measured by the IWQOL-Lite total score (+19.3 ± 8.7 vs + 11.5 ± 7.2, P < 0.001). All domain-specific improvements favored dietary intervention. [Table 6]

Table 6.

Patient-centered outcomes at 12 months

Outcome		Group A (Pharmacological) n=60		Group B (Dietary) n=60		P
Treatment satisfaction (1-5 scale)
Overall satisfaction, mean±SD		3.6±0.9		4.5±0.6		<0.001
Perceived control over weight, mean±SD		3.4±1.0		4.7±0.5		<0.001
Confidence in long-term maintenance, mean±SD		3.2±1.1		4.3±0.8		<0.001
Satisfaction with support received, mean±SD		3.5±0.8		4.6±0.6		<0.001
IWQOL-Lite scores
Total score at baseline, mean±SD		62.4±15.7		61.8±16.3		0.86
Total score at 12 months, mean±SD		73.9±14.2		81.1±12.8		0.012
Total score change, mean±SD		+11.5±7.2		+19.3±8.7		<0.001
IWQOL-Lite domain score changes
Physical function, mean±SD		+9.8±5.4		+16.2±6.8		<0.001
Self-esteem, mean±SD		+10.3±6.1		+18.7±7.3		<0.001
Sexual life, mean±SD		+8.7±5.9		+14.6±7.2		<0.001
Public distress, mean±SD		+11.2±6.5		+17.8±7.9		<0.001
Work productivity, mean±SD		+9.6±5.7		+15.4±6.9		<0.001

IWQOL-Lite: Impact of Weight on Quality of Life-Lite questionnaire; SD: standard deviation; Higher scores indicate better quality of life; Scale range 0-100 for total and domain scores

Predictors of weight loss success

Multivariate regression (R² =0.58) identified treatment adherence as the strongest independent predictor of percentage weight loss at 12 months (β = 0.46, P < 0.001). Additional predictors included baseline BMI, increases in physical activity, younger age, and assignment to the dietary group. Sex, diabetes status, education, and smoking were not significant predictors. [Table 7].

Table 7.

Multivariate predictors of 12-month percentage weight loss

Predictor Variable		Standardized β Coefficient		95% Confidence Interval		P
Treatment adherence (good vs poor)		0.46		0.32 to 0.58		<0.001
Baseline BMI (per kg/m²)		0.24		0.11 to 0.36		0.002
Physical activity increase (per 100 MET-min/week)		0.21		0.08 to 0.33		0.006
Age (per year)		-0.19		-0.31 to -0.06		0.012
Treatment group (dietary vs pharmacological)		0.17		0.04 to 0.29		0.025
Female sex (vs male)		0.08		-0.05 to 0.21		0.24
Baseline diabetes or prediabetes (yes vs no)		-0.06		-0.19 to 0.07		0.38
Education level (university vs secondary or less)		0.05		-0.08 to 0.18		0.47
Smoking status (current vs non-smoker)		-0.04		-0.17 to 0.09		0.54

Model R²=0.58, adjusted R²=0.55, F=18.7, P<0.001; BMI: body mass index; MET: metabolic equivalent of task

Discussion

This 12-month prospective cohort study provides real-world evidence comparing pharmacological therapy with intensive dietitian-led intervention in adults with obesity in Baghdad. Although pharmacological therapy was associated with a faster early decline in weight, dietary intervention achieved more sustainable improvements in body composition, metabolic health, physical activity, adherence, and patient-centered outcomes. These findings align with international evidence indicating that lifestyle modification remains the foundation of obesity management.[17,18] Because of the non-randomized pragmatic design, findings should be interpreted as associations rather than causal effects. While baseline characteristics were balanced and multivariate analysis adjusted for key confounders, residual or unmeasured confounding such as socioeconomic status, health literacy, motivation, and prior weight-loss attempts may have influenced treatment selection and outcomes.

Patterns of weight-loss of this study are based on known physiological and behavioral dynamics. The early rapid deterioration and plateau of pharmacological group is in line with the already established metabolic adaptation, compensatory, and adherence deterioration of pharmacotherapy.[19] In contrast, the steady year-long decline in the dietary group supports previous findings showing that structured lifestyle interventions, when conducted by trained counselors and can achieve clinically meaningful and durable reductions.[20]

There were clinically significant differences in body-composition between groups. The dietary intervention preserved lean mass more effectively, and producing a higher proportion of fat-mass loss relative to total weight loss. Skeletal muscle preservation is essential to the maintenance of resting metabolic rate and weight regain prevention in the long-term.[21] These findings support that evidence which high-quality dietary patterns, adequate protein intake, and behavioral engagement facilitate to compose a healthier weight-loss.[22]

Despite the slight difference in absolute weight loss with pharmacological therapy, the dietary group had superior improvements in LDL-cholesterol, fasting glucose, systolic blood pressure, and physical activity. These findings are aligned with the studies showing that dietary quality improvement (increased intake of unsaturated fats, whole grains, vegetables, and fiber) provide cardiometabolic benefits independent of weight change.[23,24] These results are consistent with earlier lifestyle-based diabetes-prevention studies as the rates of reversion to normal glycemia are higher in participants with prediabetes.[25,26]

The adherence was a major determinant of success, which consistent with evidence that long-term engagement is more influential than the theoretical efficacy of any single modality.[27] Adherence to medication significantly declined after 12 months due to gastrointestinal adverse effects and perceived benefit reduction, which is similar to adherence issues noted in clinical practice.[28,29] Meanwhile, the dietary group had the advantage of regular counseling sessions, self-monitoring tools and more patient autonomy contributing to higher adherence and satisfaction factors illustrated to enhance long-term behavioral maintenance.[30]

The behavioral and psychological benefits of individualized dietary counseling are supported by greater improvements of the quality of life across multiple IWQOL-Lite domains. well-recognized mediators of successful weight-management behaviors improve self-efficacy, problem-solving, and perceived control.[16]

From a policy perspective, these findings highlight the importance of expanding access to qualified dietitians in Iraq. Intensive dietary interventions offer long-term sustainable outcomes, avoid medication-related side effects, and can reduce long-term health care expenditures on diabetes and cardiovascular disease. Although pharmacological therapy still valuable particularly with patients who are more severely obese or limited response to lifestyle change it should complement, rather than replace, structured lifestyle counseling.

Limitations, weaknesses, and strengths

This study has a number of limitations. The pragmatic, non-randomized design can introduce selection bias, and despite generally balanced baseline characteristics, unmeasured confounding cannot be ruled out, potentially affecting treatment outcomes. The pharmacological group consisted of two different pharmacotherapies and this introduced a heterogeneity that could not be further analyzed due to limited sample size. Reporting bias may also be present because of the use of self-reported compliance to the dietary intervention, physical activity, and quality of life, which are patient-reported. Although the 12-month follow-up is relatively long in terms of regional data, it is remains insufficient to fully evaluate long-term weight-regain patterns. The urban specialty clinics setting of the study restricts generalization and the lack of cost-effectiveness analysis constrains the policy interpretation. Also, newer and more efficient agents like semaglutide and tirzepatide were not included because of limited availability. In spite of these weaknesses, the study has significant strengths, such as a relatively long follow-up period, evaluation of two commonly used real-world treatment pathways, a comprehensive assessment of metabolic, behavioral, and quality-of-life outcomes, a pragmatic design, which increases the external validity, and a detailed analysis of adherence and patient-centered outcomes that are typically underreported.

Study suggestions for future research:

Several of the priorities that should be addressed in future research include: (1) extended follow-up studies beyond 12 months to assess weight maintenance and durability; (2) separate evaluation of different pharmacotherapies to identify responder profiles; (3) cost-efficiency analysis of the treatment options; (4) exploration of hybrid or sequential treatment models; (5) study of newer GLP-1 agonists in such a population; (6) study of implementation strategies to scale up dietitian-led programs to resource-limited settings; and (7) qualitative research on patient preferences and impediments to continued engagement.

Conclusion

This 12-month prospective cohort study demonstrates that intensive, dietitian-led dietary intervention is associated with more sustainable improvements in body composition, metabolic health, adherence, physical activity, and quality of life than pharmacological therapy. While medications produced faster initial weight loss, their benefits plateaued and were associated with more adverse events and reduced adherence. From a health-policy perspective, the findings support prioritizing structured, dietitian-delivered lifestyle programs as first-line obesity care, given their scalability, cost-effectiveness, and alignment with international standards. Pharmacological therapy remains valuable for selected patients but should be used as an adjunct within integrated care models. National obesity strategies in Iraq should focus on expanding and training the dietitian workforce, integrating nutrition services into primary care, strengthening referral pathways, establishing reimbursement for evidence-based counseling, and developing quality indicators aligned with international benchmarks. Future research should assess long-term outcomes, cost-effectiveness, subgroup responses to pharmacotherapy, and hybrid or sequential treatment models.

AI policy statement

AI tools were used only to assist in language editing and organization of the manuscript. No AI tools were used for data generation, statistical analysis, image creation, or interpretation of study results. The authors remain fully responsible for all scientific content and guarantee adherence to publication ethics.

Abbreviations

BMI – Body Mass Index; LDL – Low-Density Lipoprotein; HDL – High-Density Lipoprotein; CI – Confidence Interval; MET – Metabolic Equivalent of Task; HbA1c – Glycated Hemoglobin; IPAQ – International Physical Activity Questionnaire; IWQOL-Lite – Impact of Weight on Quality of Life-Lit; BIA – Bioelectrical Impedance Analysis; SD – Standard Deviation

Ethical approval

The Institutional Ethics Committee of the College of Medicine, University of Baghdad was approved the study (Reference No. 195, June 15, 2024). Study ID: OB-2024-17. Written informed consent was given by all participants. The study procedures adhered to established ethical standards, such as the principles of the Helsinki Declaration and relevant CPCSEA guidelines.

Author’s contributions

DMA and STK contributed to the conceptualization, methodology, investigation, data curation, and writing of the original draft. MFA contributed to the conceptualization, methodology, formal analysis, writing review and editing, visualization, project administration, resources, supervision, and validation. The manuscript has been read and approved by all authors, and that it represents honest work.

Data availability statement

The datasets generated and/or analyzed during the current study are available from the corresponding author on reasonable request.

Conflicts of interest

There are no conflicts of interest.

Funding Statement

Nil.