Modulation of metabolic parameters among obese diabetic individuals through a gluten-free diet.

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Learn more: PMC Disclaimer | PMC Copyright Notice BMC Nutr . 2026 Apr 20;12:102. doi: 10.1186/s40795-026-01316-1 Modulation of metabolic parameters among obese diabetic individuals through a gluten-free diet Faiza Naeem 1 , Sana Noreen 1, ✉ , Hazeefa Sultan 1 , Patrick Maduabuchi Aja 2, ✉ Author information Article notes Copyright and License information 1 University Institute of Diet and Nutritional Sciences, The University of Lahore, Lahore, Pakistan 2 Department of Biochemistry, Faculty of Biomedical Sciences, Kampala International University, Kampala, Uganda ✉ Corresponding author. Received 2025 Aug 22; Accepted 2026 Mar 31; Collection date 2026. © The Author(s) 2026 Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/ . PMC Copyright notice PMCID: PMC13231638  PMID: 42010674 Abstract Background Obesity and type II diabetes mellitus are major public health concerns often associated with liver and metabolic complications. Methodology The study received ethical approval from the Institute Research Ethics Board (IREB), University of Lahore (UOL/IREB/25/09/0008). This study aimed to compare the effects of a conventional diet and a gluten-free diet on metabolic health in obese individuals with diabetes over 12 weeks. A total of 108 participants, aged 30–55, were randomly assigned to groups. Key health indicators, including anthropometric measurements (BMI and waist circumference), blood pressure, fasting blood glucose, lipid profile, liver enzymes (alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP)), and HOMA-IR, were evaluated before and after a 12-wk intervention. Results A Gluten-free diet group experienced significantly greater reductions in BMI ( p < 0.001) and marked improvements in blood pressure, glucose levels, insulin resistance, lipid profile, and liver enzymes ( p < 0.001), compared to the modest improvements seen in the conventional diet group. Conclusion Findings suggested that a gluten-free diet may serve as an effective strategy for metabolic management in obese diabetic patients. Further research is warranted to assess the long-term effect. This trial is registered on 8th Aug, 2025 at https://clinicaltrials.gov/study/NCT07127055 . Keywords: Gluten-free Diet, Metabolic Parameters, Obesity, Diabetes Introduction In the modern, industrialized setting, eating habits have extensively moved toward increased consumption of ultra-processed, energy-dense, and nutrient-poor foods. These food patterns are some of the major drivers of the global rise in non-communicable diseases, such as obesity and metabolic syndrome [ 1 , 2 ]. The World Health Organization (WHO) indicated that in 2022, over 1.9 billion individuals were overweight, with more than 650 million classed as obese, a number that has almost tripled since 1975 [ 3 ]. Obesity is an independent illness and a major risk factor for type 2 diabetes, hypertension, dyslipidemia, cardiovascular disease, and some malignancies. A balanced, nutrient-rich diet is a fundamental pillar of obesity prevention as well as metabolic control. The essential nutrients carbohydrates, proteins, fats, vitamins, and minerals play vital roles in energy metabolism, tissue repair, hormonal homeostasis, and immune function [ 4 , 5 ]. Nevertheless, nutrition patterns of unbalanced, especially high-refined carbohydrate and gluten-containing food intake, have been associated with adverse metabolic outcomes, such as insulin resistance, systemic inflammation, and gut dysbiosis. Gluten is a mixture of storage proteins gliadin and glutenin, with the main presence in wheat, barley, and rye. Upon mixing with water, the proteins create a viscoelastic network responsible for bread’s chewiness. Although gluten is safe for the vast majority of people, it has been linked to negative health consequences for some groups, such as those with celiac disease (~ 1% of the world population) or non-celiac gluten sensitivity (estimated 3–6%) [ 6 , 7 ]. A gluten-free diet (GFD) entails the absence of all wheat, barley, rye, and related grains. Historically used to treat gluten-related illness, it is increasingly being considered in the metabolic health space based on emerging data suggesting its ability to regulate inflammatory markers, enhance gut barrier function, and normalize lipid and glucose metabolism [ 8 ]. Current clinical and animal research has shown that GFD is capable of decreasing fat mass, enhancing insulin sensitivity, and affecting the composition of gut microbiota. High-fat gluten-free-fed mice had lower weight gain, decreased adiposity, and enhanced inflammatory status when compared to their gluten-fed counterparts [ 9 ]. A clinical trial indicated that obese patients who consumed a GFD for 12 weeks had reductions in body mass index (BMI), fasting insulin, and C-reactive protein (CRP) levels, which was indicative of a possible metabolic advantage [ 10 ]. In addition, observational studies have revealed that gluten-free diets, when well-balanced and dense with whole foods, can be associated with improvements in HbA1c, lipid profiles (Total cholesterol, Low Density Lipoprotein, High Density Lipoprotein, and triglycerides), and blood pressure, especially in overweight people with metabolic syndrome [ 11 ]. Nonetheless, care must be exercised, as gluten-free processed food tends to be low in fiber but rich in sugar and fat content and has the potential to negate benefits if not properly regulated [ 12 , 13 ]. Although GFD is firmly established concerning gluten-related disorders, its ability to modulate metabolic factors among obese individuals who are not gluten sensitive remains an area of limited investigation. Therefore, this study aims to investigate the impact of a gluten-free diet on metabolic parameters among obese patients, focusing on key indicators such as BMI, fasting blood glucose, insulin resistance with Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), lipid profile, and liver enzymes. By addressing this gap, the study aims to evaluate whether GFD can be a viable adjunct dietary strategy for enhancing metabolic health outcomes in individuals with obesity. Alternate Hypothesis There is an effect of Gluten free diet on metabolic parameters among obese diabetic patients. Primary Outcomes of the study The primary outcome of the study was to evaluate the effect of a gluten-free diet on fasting glucose, insulin sensitivity, and lipid profile, particularly HDL levels. Materials and methods Ethics approval The study was approved by the Institute Research Ethics Board (IREB), University of Lahore, Lahore, Pakistan (UOL/IREB/25/09/0008). All procedures performed in studies involving human participants were conducted following the ethical standards of the institutional research committee and with the 1964 Declaration of Helsinki and its later amendments. This trial is also registered at https://clinicaltrials.gov/study/NCT07127055 on 8th Aug 2025. Written Informed consent was obtained from all participants, who were fully briefed on the study’s purpose, procedures, risks, and benefits, with the option to ask questions and withdraw at any time. Study design The research trial, a randomized controlled trial (RCT), was carried out at the Dilawar Hussain Foundation, Diabetes Management Center, Lahore, Pakistan. An intervention with a tailored gluten-free diet of 1800–2000 kcal/day was planned. Inclusion and Exclusion Criteria : Patients who were obese diabetic adults of both genders, aged 30 to 55 years, with a body mass index (BMI) > 25 kg/m², fasting glucose level > 135 mg/dL, elevated parameters of lipid profile, blood pressure > 135/85 mmHg, and (HOMA-IR) > 2.57 were included in the study. Patients with a diagnosis of celiac disease, irritable bowel syndrome, some cancers such as colorectal cancer, small intestinal lymphoma, pancreatic cancer, and gastric cancer, genetic illnesses, respiratory illnesses, and psychiatric illnesses were excluded from the study, the possibility of confounding influences that may affect the metabolic outcomes or food compliance. These confounding factors were excluded through detailed medical history assessment, clinical examination, laboratory investigations, and review of previous medical records at baseline screening. Participants meeting any exclusion criteria were not enrolled in the study. Methods of data collection Sample Size: A total of 115 volunteers who met the inclusion criteria were recruited into the study. Seven participants left the study due to personal issues; The study was subsequently conducted on the remaining 108 patients, which were divided into two equal groups ( n = 54 in each group), using computer generated simple randomization method as mentioned in Fig. 1 [ 14 ]. The final dataset comprised anthropometric data: weight, height, body mass index, and waist circumference, 24-hour dietary recall, as outlined. In addition, fasting glucose level, HOMA-IR, systolic and diastolic blood pressure, and lipid profiles in serum were measured using the same procedure [ 14 ]. Fig. 1. Open in a new tab Flow chart of the study Participants were randomly assigned to two groups using a computer-generated simple randomization method. The allocation sequence was prepared by an independent researcher to ensure allocation concealment. Group T 1 received a standard diet, whereas Group T 2 received a gluten-free diet for 12 weeks. An 1800–2000 kcal/day diet was nutritionally comparable, 50–55% of calories were from carbohydrates, 15–20% protein, and 25–30% fat. Dietary fiber was provided through fruits, vegetables, legumes, and appropriate whole grains. The gluten-free variant omitted all sources of wheat, rye, and barley and thus was the ideal option for those needing a gluten-free diet, as mentioned in Table 1 . Follow-up sessions were conducted on alternate days during the 12-week intervention through in-person visits or telephone calls. Dietary compliance was assessed using 24-hour recalls and 3-day food records to confirm adherence to the prescribed 1800–2000 kcal/day gluten-free diet. Participants received individualized meal plans, and adherence (≥ 80%) was reinforced through regular counseling and monitoring of body weight and fasting glucose levels. At the end of week 12th, biochemical tests were performed for all the subjects. The post-interventional measurements between the two groups were then compared to assess the metabolic effects of the gluten-free diet, including changes in fasting glucose, insulin levels, HOMA-IR (insulin resistance), lipid profile parameters (total cholesterol, LDL-C, HDL-C, triglycerides), body mass index (BMI), and blood pressure. This comparison was used to test the main hypothesis of the study, as mentioned in Table 2 . Table 1. Comparison of standard and gluten-free diet plans for obese diabetic patients Meals Standard Diet Plan Gluten-Free Diet Plan Early morning 1 cup Cinnamon Tea 1 cup Cinnamon Tea Breakfast 1 boiled egg + 2 slices whole wheat bread + 1 cup mixed fruit (papaya, guava) 1 boiled egg + 2 slices gluten-free bread + 1 cup mixed fruit (papaya, guava) Mid-Morning 1 apple + 1 small cucumber or carrot sticks 1 apple + 1 small cucumber or carrot sticks Lunch 1 whole wheat chappati + 1 cup lentils + mixed vegetable salad (lettuce, tomato, cucumber) + 6 almonds 1 cup cooked quinoa or brown rice + 1 cup lentils + mixed vegetable salad (lettuce, tomato, cucumber) + 6 almonds Afternoon snack 1 cup low-fat yogurt + 1 orange or ½ cup pomegranate seeds + 4 cashews + 5 pistachios 1 cup low-fat yogurt + 1 orange or ½ cup pomegranate seeds + 4 cashews + 5 pistachios Dinner 1 cup grilled chicken curry + 1 whole wheat roti + steamed broccoli and spinach 1 cup grilled chicken curry + 1 gluten-free roti (corn or rice flour) + steamed broccoli and spinach Bedtime snack 1 cup warm skim milk + 1 tbsp ground flaxseed 1 cup warm skim milk + 1 tbsp ground flaxseed Open in a new tab Table 2. Treatment plan of the study Plan Control Group T 1 Treatment Group T 2 Diet Type Conventional treatment + Standard Diet Conventional treatment + Gluten-free diet Calories 1800–2000/day Duration 12 Weeks Target Group 30-55 ears Open in a new tab Anthropometric measurement Baseline anthropometric measurements, including weight, height, BMI, and waist circumference, were recorded following standard clinical procedures. Weight was measured with a calibrated electronic scale (Model: Seca 813, Seca GmbH & Co. KG, Hamburg, Germany) while subjects wore light clothing and were barefoot. Height was measured using a calibrated stadiometer (Model: Seca 217, Seca GmbH & Co. KG, Hamburg, Germany) with subjects standing erect and barefoot. BMI was calculated as weight (kg) divided by height squared (m²) [ 14 ]. Waist circumference was measured with a non-elastic tape placed midway between the lowest rib and iliac crest, ensuring the tape touched the skin without compressing it [ 15 ]. 24-hour dietary recall method The 24-hour dietary recall was conducted over three non-consecutive days per participant to better capture habitual dietary intake. A multi-pass approach ensured detailed and accurate reporting of food, portion sizes, and preparation methods. Recalls on non-consecutive days captured dietary variation, and data were analyzed using validated tools to estimate nutrient intake [ 16 ]. Biochemical assessment Assessment of lipid profile Blood samples for baseline and follow-up tests were collected in EDTA-treated tubes to assess hematological parameters. TC, TG, and HDL-C were measured using enzymatic colorimetric assays. TC and TG were quantified via enzymatic reactions producing colored dyes, while HDL-C was determined after precipitating apolipoprotein B-containing lipoproteins. Color intensity was measured with a UV–Vis spectrophotometer/colorimeter (Model UV-1800, Shimadzu, Kyoto, Japan) at 500 nm (TC) and 505 nm (TG) [ 17 ], whereas LDL-C concentration was checked with the help of a Friedewald formula [ 18 ]. The following equation was used to calculate very low-density lipoprotein cholesterol (VLDL). Assessment of liver function Aspartate aminotransferase (AST), alkaline phosphatase (ALP), and alanine aminotransferase (ALT) were measured using standard enzymatic colorimetric assays with a UV–Vis spectrophotometer (Model UV-1800, Shimadzu, Kyoto, Japan) [ 19 ]. HOMA-IR HOMA-IR was calculated to estimate insulin resistance from fasting blood glucose and fasting insulin. Blood was obtained from the subjects after an overnight fast of 8–12 h. Serum insulin was measured by a validated enzyme-linked immunosorbent assay (ELISA), and fasting blood glucose was measured by a glucose oxidase assay [ 20 ]. HOMA-IR value was subsequently calculated by the following formula: This method provides an approximation of insulin resistance, with higher values being related to higher resistance. A HOMA-IR above 2.57 was used to denote insulin resistance in the present study, whereas, normal range of HOMA-IR is 0.5–2.4 [ 21 , 22 ]. Statistical analysis Data analysis was performed using SPSS version 25. Continuous variables were summarized as mean ± standard deviation, while categorical variables were presented as frequencies and percentages. Baseline and post-study comparisons were made using paired sample t-tests, with significance set at p ≤ 0.05 [ 23 ]. Results Demographic and socioeconomic characteristics of the subjects of both groups were equal in terms of gender and age distribution. Distribution of age in both groups was 30 to 55 years, and no difference was noted ( p = 0.876). Gender was also nearly equal, with males being 48% in Group T 1 (Standard Diet) and 50% in Group T 2 (Gluten-Free Diet), and no statistically significant difference was noted ( p = 0.823). Marital status was similar between groups, with 85% married in Group T 1 and 88% in Group T 2 ( p = 0.642). There were no significant differences between groups in overall socioeconomic class distribution (upper, middle, and lower classes). However, important variations were observed in specific socioeconomic indicators. A significantly higher proportion of participants in Group T2 had secondary education or above compared to Group T1 (85% vs. 65%, p = 0.01). Similarly, employment rates were significantly higher in Group T2 than in Group T1 (75% vs. 55%, p = 0.02). In addition, knowledge regarding the importance of a gluten-free diet was significantly greater in Group T2 (45%) compared to Group T1 (20%) ( p = 0.003), as presented in Table 3 . These differences may have influenced dietary adherence and metabolic outcomes, and therefore should be considered when interpreting the independent effects of the gluten-free diet. Future studies should adjust for these variables to minimize potential confounding. Table 3. Demographic characteristics of participants Characteristic Group T 1 Group T 2 p -value Age Range (years) 30–55 30–55 0.876 t Male 48% 50% 0.823 # Female 52% 50% Marital Status 85% 88% 0.642 # Socioeconomic Status (Middle class, %) 70% 68% 0.778 # Education Level (≥ Secondary, %) 65% 85% < 0.01 *# Employment Level (Employed, %) 55% 75% < 0.02 *# Knowledge of Gluten-Free Diet Importance (Aware, %) 25% 54% < 0.003 *# Open in a new tab Abbreviation * = Highly significant, # =chi-square, t =t-test Body mass index The Body Mass Index (BMI) is a significant anthropometric indicator of body fat and weight status categorization, correlating well with the risk of most metabolic and cardiovascular disorders. In the present study, both intervention groups exhibited a notable improvement in BMI after the 12-week intervention. In the control diet group (T 1 ), the mean BMI decreased from 30.63 ± 2.4 kg/m² to 29.80 ± 2.1 kg/m², respectively. The decrease was statistically significant ( p = 0.042). The gluten-free diet group (T 2 ) also exhibited an even better response, with the drop in BMI from 30.83 ± 2.3 kg/m² to 27.23 ± 2.0 kg/m². The change was highly significant ( p = 0.001). These findings illustrate that although both diets helped with weight control, the gluten-free diet was superior in lowering BMI in obese individuals, as mentioned in Table 4 . For waist circumference, both groups had very minimal, statistically nonsignificant changes. In the T 1 group, waist circumference did not decrease significantly from 108.2 ± 11.2 cm to 107.6 ± 10.2 cm ( p = 0.321), whereas in the T 2 group, it decreased from 109.5 ± 10.4 cm to 107.3 ± 10.1 cm ( p = 0.089). Though the T 2 group had a numerically more reduction as shown in Table 4 . Although BMI showed significant improvement, the absence of a statistically significant reduction in waist circumference suggests that central adiposity may respond more slowly to dietary intervention or require a longer duration to demonstrate measurable changes. Table 4. Effect of gluten-free diet on BMI (kg/m 2 ) among obese diabetic patients Groups N Mean ± SD Std. Error Mean P-value BMI (kg/m 2 ) T 1 Pre 54 30.63 ± 2.4 0.39 0.042 * Post 29.80 ± 2.1 0.34 T 2 Pre 54 30.83 ± 2.3 0.37 < 0.001 ** Post 27.23 ± 2.1 0.32 Waist circumference (cm) T 1 Pre 54 108.2 ± 11.2 1.52 0.321 NS Post 107.6 ± 10.2 1.48 T 2 Pre 54 109.5 ± 10.4 1.47 0.089 NS Post 107.3 ± 10.1 1.41 Open in a new tab Abbreviation NS = non-significant, **=Highly Significant, * Significant Blood pressure Blood pressure is an important indicator of cardiovascular health and part of the management of metabolic diseases such as diabetes and obesity. Systolic and diastolic blood pressure measurements were taken before and after the diet regimen in both groups of this study. In the (Conventional Diet) T 1 group, average systolic blood pressure also decreased from 139.2 ± 6.4 mmHg to 134.1 ± 5.2 mmHg, respectively. Similarly, diastolic pressure decreased from 89.6 ± 4.8 mmHg to 86.9 ± 4.5 mmHg, and this was a statistically significant reduction ( p = 0.039). In the T 2 group (Gluten-Free Diet), the reduction was greater. Systolic pressure declined from 140.2 ± 6.1 mmHg to 129.3 ± 5.6 mmHg, and diastolic pressure from 89.2 ± 5.1 mmHg to 82.6 ± 4.2 mmHg, as shown in Table 5 . These reductions were highly significant ( p < 0.001), indicating that the gluten-free diet can be more effective in controlling blood pressure than the normal diet. Table 5. Effect of gluten-free diet on blood pressure (mmHg) among obese diabetic patients Groups N Systolic BP Mean ± SD Std. Error Mean Diastolic BP Mean ± SD Std. Error Mean P -value T 1 Pre 54 139.2 ± 6.4 0.91 89.6 ± 4.8 0.76 0.039* Post 134.1 ± 5.2 0.94 86.9 ± 4.5 0.73 T 2 Pre 54 140.2 ± 6.1 1.10 89.2 ± 5.1 0.81 < 0.001** Post 129.3 ± 5.6 0.93 82.6 ± 4.2 0.76 Open in a new tab Abbreviation, **=Highly Significant, * Significant Fasting blood glucose levels Fasting blood glucose levels were measured in both groups before and after the intervention. In the conventional diet group (T 1 ), the mean fasting glucose was 141.5 ± 6.48 mg/dL at baseline and 141.7 ± 6.68 mg/dL post-intervention, showing no significant change ( p = 0.282). However, in the gluten-free diet group (T 2 ), a significant reduction in fasting glucose was observed, with levels decreasing from 140.6 ± 6.12 mg/dL at baseline to 128.5 ± 5.23 mg/dL after the intervention ( p = 0.006) as shown in Table 6 . This indicates that the gluten-free diet had a beneficial effect on fasting glucose levels in the participants. Table 6. Effect of gluten-free diet on fasting glucose (mg/dL) among obese diabetic patients Groups N Mean ± SD fasting Glucose (mg/dL) Std. Error Mean P -value T 1 Pre 54 141.5 ± 6.48 0.88 0.282 NS Post 141.7 ± 6.68 0.90 T 2 Pre 54 140.6 ± 6.12 0.83 0.006* Post 128.5 ± 5.23 0.71 Open in a new tab NA = non-significant, ** =Highly Significant, * =Significant Total lipid profile In this research, lipid profile indices—namely, total cholesterol (TC), low-density lipoprotein (LDL), triglycerides (TG), and high-density lipoprotein (HDL) were measured before and following the dietary interventions among the conventional diet group (T 1 ) and the gluten-free diet group (T 2 ) Table 7 showed the effect of gluten free diet and conventional diet on patients. It showed that in the T 1 group, TC increased non- significantly from 230.11 ± 9.71 mg/dL to 233.79 ± 4.24 mg/dL although the difference was not significant ( p = 0.062). The T 2 group showed a significant reduction in TC from 227.49 ± 4.21 mg/dL to 213.20 ± 8.91 mg/dL ( p < 0.001), indicating improved control of cholesterol. In the case of LDL, the T 1 group revealed a small but significant increase from 143.42 ± 2.86 mg/dL to 145.77 ± 9.79 mg/dL ( p = 0.034). The T 2 group instead revealed a significant decrease of LDL levels, from 149.20 ± 4.80 mg/dL to 138.83 ± 8.09 mg/dL ( p = 0.004), demonstrating a protective action against cardiovascular risk. Triglyceride (TG) level did not change in the T 1 group (284.02 ± 7.85 mg/dL to 284.43 ± 7.88 mg/dL, p = 0.277), whereas the T 2 group decreased statistically from 261.37 ± 6.57 mg/dL to 260.06 ± 6.57 mg/dL ( p < 0.001), signifying enhanced fat metabolism. HDL, being positive for cardiovascular health, was found to increase slightly in the T 1 group, from 31.66 ± 2.22 mg/dL to 32.64 ± 4.91 mg/dL ( p = 0.070, not significant). However, there was a notable and statistically significant increase in the T 2 group, from 31.72 ± 2.68 mg/dL to 36.66 ± 2.62 mg/dL ( p < 0.001), reflecting an improvement in lipid balance. Overall, the gluten-free diet was associated with improvement in all lipid profile parameters, suggesting its potential role in the control of cardiovascular risk factors. Table 7. Effect of gluten-free diet on lipid profile among obese diabetic patients Lipid markers Groups N Mean ± SD Std. Error Mean P - Value TC (mg/dL) T 1 Pre 54 230.11 ± 9.71 1.32 0.062 NS Post 233.79 ± 4.24 0.58 T 2 Pre 54 227.49 ± 4.21 0.57 < 0.001* Post 213.20 ± 8.91 1.21 LDL (mg/dL) T 1 Pre 54 143.42 ± 2.86 0.39 < 0.034* Post 145.77 ± 9.79 1.33 T 2 Pre 54 149.20 ± 4.80 0.65 < 0.004* Post 138.83 ± 8.09 1.10 TG (mg/dL) T 1 Pre 54 284.02 ± 7.85 1.07 0.277 NS Post 284.43 ± 7.88 1.08 T 2 Pre 54 261.37 ± 6.57 0.89 < 0.000* Post 260.06 ± 6.57 0.81 HDL (mg/dL) T1 Pre 54 31.66 ± 2.22 0.30 0.070 NS Post 32.64 ± 4.91 0.67 T 2 Pre 54 31.72 ± 2.68 0.36 < 0.000* Post 36.66 ± 2.62 0.35 Open in a new tab NS = non-significant, ** =Highly Significant, * =Significant Homeostatic model assessment of insulin resistance HOMA-IR is a crucial marker of insulin sensitivity used extensively in the evaluation of metabolic health. In the present study, there was no statistically significant difference in HOMA-IR values pre-to-post-intervention in Group T 1 (Conventional Diet), with the mean being maintained at a constant 2.68 ± 0.08 to 2.68 ± 0.07 ( p = 0.972, NS). Group T 2 (Gluten-Free Diet) showed a statistically significant decrease in HOMA-IR values from 2.75 ± 0.10 at baseline to 2.40 ± 0.10 post-intervention ( p < 0.001) as shown in Table 8 . The difference is an indicator of increased insulin sensitivity in subjects on a gluten-free diet regimen. Table 8. Effect of gluten-free diet on HOMA IR among obese diabetic patients Groups N HOMA IR Mean ± SD Std. Error Mean P -Value T 1 Pre 54 2.68 ± 0.08 0.019 0.972 NS Post 2.68 ± 0.07 0.010 T 2 Pre 54 2.75 ± 0.10 0.014 0.000* Post 2.40 ± 0.10 0.013 Open in a new tab NS = non-significant, ** =Highly Significant, * =Significant Liver function test The findings reflected significant differences in liver enzyme reactions between the control diet (T 1 ) and gluten-free diet (T 2 ) groups in obese diabetics. In the T 1 group, there were no statistically significant changes in AST, ALT, or ALP levels after the intervention diet, with p-values of 0.235, 0.216, and 0.356, respectively. The T 2 group demonstrated reductions in AST and ALT levels upon the adoption of a gluten-free diet. AST decreased from 48.0 ± 9.9 U/L to 34.2 ± 9.4 U/L ( p < 0.002), and ALT fell from 55.1 ± 10.4 U/L to 38.8 ± 8.2 U/L ( p < 0.001). ALP also reduced from 110.9 ± 15.2 U/L to 98.4 ± 13.5 U/L in the T 2 group, exhibiting a near-significant trend ( p = 0.059) as shown in Table 9 . These results indicate that a gluten-free dietary intervention can largely enhance liver function, especially by decreasing aminotransferase levels, in obese patients with diabetes. Table 9. Effect of gluten-free diet on liver function test (U/L) among obese diabetic patients Lipid markers Groups N Mean ± SD Std. Error Mean P - Value AST T 1 Pre 54 47.4 ± 9.5 1.33 0.235 NS Post 46.1 ± 9.3 1.25 T 2 Pre 54 48.0 ± 9.9 1.29 < 0.002 ** Post 34.2 ± 9.4 1.05 ALT T 1 Pre 54 54.2 ± 10.2 1.43 0.216 NS Post 53.0 ± 9.6 1.35 T 2 Pre 54 55.1 ± 10.4 1.36 < 0.001 ** Post 38.8 ± 8.2 1.21 ALP T 1 Pre 54 109.3 ± 14.6 2.04 0.356 NS Post 108.1 ± 13.2 1.89 T 2 Pre 54 110.9 ± 15.2 2.06 0.059 * Post 98.4 ± 13.5 1.85 Open in a new tab NS = non-significant, ** =Highly Significant, * =Significant Discussion A gluten-free diet has been extensively studied and is now utilized by consumers more broadly rather than being a specialized treatment for just a few diseases [ 9 ]. In addition to patients with celiac disease, other conditions for which the gluten-free diet has been recognized as helpful include gluten ataxia, dermatitis herpetiformis, cognitive decline, irritable bowel syndrome, inflammatory bowel disease, non-celiac gluten sensitivity, and metabolic disorders [ 24 ]. The demographic and socioeconomic characteristics of the participants in the gluten-free diet group (T2) and the control diet group (T1) were generally similar in terms of gender composition, age, and marital status. The findings of present study are in line with randomized controlled intervention studies, where demographic features are made equivalent to minimize confounding. The same demographic features are reported in other diet intervention trials, where age and sex distribution must be controlled because of their proven impact on metabolic response and diet adherence [ 25 , 26 ]. Significant differences in education, employment, and gluten-free diet awareness reflect a gap that affects health literacy, nutritional knowledge, and access to specialty foods, as supported by previous study [ 27 ]. Improved awareness and socioeconomic status in Group T 2 probably enabled improved diet compliance and may be one of the reasons for the larger metabolic changes seen. The socioeconomic status has also been found in earlier studies to contribute to food quality and health status. Higher education levels were associated with better dietary behaviors and better metabolic control in individuals on special diets [ 26 ], it was also found that working boosts dietary adherence through the creation of economic security and regular schedules [ 28 ]. In spite of these variations, it is noteworthy that the socioeconomic benefit in Group T 2 may lead to some confounding when attributing the metabolic benefit solely to the gluten-free diet. It is recommended that future research control for socioeconomic factors or use stratified analyses to isolate the effects of diet. Both diet intervention led to a significant decrease in BMI; nonetheless, the GFD group (T 2 ) achieved a much greater reduction compared with the control diet group. This is in agreement with previous study [ 14 ], which found that waist circumference and BMI significantly decreased in metabolic syndrome subjects after 8 weeks. This BMI decrease could be multifactorial in mechanism. Gluten has been suggested to induce systemic inflammation and change gut permeability, potentially leading to obesity and metabolic disturbance [ 8 ]. With the removal of gluten, inflammation might reduce, and nutrient absorption might increase, leading to weight loss. By contrast, it was demonstrated in other RCT relatively smaller weight changes in non-celiac subjects, suggesting that response might be variable and subject to adherence and baseline metabolic status [ 26 ]. The marked decrease in both diastolic and systolic blood pressure in the GFD group is remarkable. The findings are consistent with existing literature [ 29 ], who reported enhanced vascular endothelial function and lower hypertension risk in patients who followed a gluten-free diet. The reduction in blood pressure could be attributed to lowered systemic inflammation and oxidative stress, which are well-established causative factors in hypertension [ 30 ]. Additionally, enhanced lipid metabolism in the GFD group would have been a factor in improved vascular health. Compared with the traditional diet group, it had smaller but significant decreases, supporting the fact that food quality is essential for blood pressure control. According to the findings observed, the gluten-free diet (GFD) showed a significant effect on fasting blood glucose levels. In the control group receiving the traditional diet (T 1 ), which indicates little metabolic effect from the dietary intervention. Conversely, GFD group participants (T 2 ) improved glycemic control. These findings corroborate the current literature indicating the therapeutic potential of gluten-free diets in enhancing glucose metabolism, especially among subjects with metabolic syndrome or insulin resistance [ 14 ]. In a clinical trial conducted, it was found that a 12-week gluten-free dietary intervention significantly improved glycemic markers, including fasting glucose and HbA1c levels, in overweight adults with impaired glucose tolerance [ 14 ]. Similarly, another study reported that a gluten-free diet could reduce systemic inflammation and improve insulin sensitivity, which may contribute to better glycemic control [ 24 ]. The absence of substantial reduction in fasting glucose and HOMA-IR in the control diet group is in comparison with the GFD group. Reduction in insulin resistance can be mediated by changes in gut microbiota composition and lower intestinal permeability, factors involved in metabolic syndrome pathogenesis [ 11 ]. Inconsistent effects of GFD on glucose metabolism in non-celiac groups have, however, been reported by other studies [ 26 ], necessitating further research to determine the subgroups most likely to benefit. The lipid parameter improvement in the GFD group, reductions in total cholesterol, LDL, and triglycerides, with enhanced HDL, testifies to the cardioprotective function of gluten restriction [ 31 ]. The decreases in LDL and triglycerides may have been due to decreased systemic inflammation and better hepatic lipid metabolism [ 2 ]. However, the control diet group had a less rise in LDL and no significant alterations in other lipid markers, indicating a less desirable lipid profile trend. HDL rise in the GFD group is especially noteworthy considering HDL’s role in reverse cholesterol transport and athero-protection [ 32 ]. These findings suggest the potential of GFD in altering lipid metabolism with gluten-related disorders. The current study assessed the impact of a gluten-free diet on liver function tests AST, ALT, and ALP among obese diabetic patients, in contrast to patients sustained on a standard diet. Our results indicated that whereas the standard diet group (T 1 ) had no significant alterations in liver enzyme levels, the gluten-free diet group (T 2 ) had marked decreases in AST and ALT levels, with a marginal reduction in ALP. The decrease in AST and ALT levels in the gluten-free group is consistent with the postulate that gluten food might be a causative agent for hepatic stress or low-grade inflammation in patients. Elevated liver enzymes, particularly transaminases, are ubiquitous in metabolic disorders and non-alcoholic fatty liver disease (NAFLD), both of which very often go together with obesity and type 2 diabetes. The enhancement of liver function indicators after a gluten-free diet could indicate that gluten withdrawal reduces hepatic inflammation or enhances liver fat metabolism [ 33 ]. The result of present study is accord with previous researches which demonstrated that patients with non-celiac gluten sensitivity and metabolic syndrome had improved liver enzyme values upon employing a gluten-free diet, which may be attributed to decreased intestinal permeability and systemic inflammation [ 34 , 35 ]. However, it was also noted that no significant hepatic effect of a gluten-free diet, in a randomized trial [ 36 ], among diabetic patients with no documented gluten sensitivity, emphasizing the importance of personalized dietary prescriptions. Conclusion This study shows that a gluten-free diet significantly enhances metabolic, cardiovascular, and hepatic health indicators in obese patients with type 2 diabetes compared to a normal diet. Volunteers following a gluten-free diet had greater declines in BMI, blood pressure, fasting glucose, and lipid levels, as well as improved insulin sensitivity and liver enzyme profiles. These data suggest that the imposition of a gluten-free dietary regimen could be a valuable and non-pharmacologic approach to the treatment of obesity-associated complications and general metabolic health in diabetic subjects. Recommendation This research discovered that a gluten-free diet produced significant improvements in major health indicators among obese subjects with type 2 diabetes compared to a standard diet. Subjects on the gluten-free diet had increased decreases in BMI, blood pressure, fasting glucose, lipid concentration, liver enzymes, and insulin resistance. Although waist circumference alterations were small, overall metabolic well-being improved significantly. The research advises incorporating gluten-free diets into diabetes care. Additional long-term research will be necessary to support these effects and examine underlying mechanisms. Limitations The limitations are a brief intervention duration, self-assessment of diet adherence, and limited generalizability, supporting the need for more extensive and longer-term future studies. Acknowledgements The Authors acknowledge the University of Lahore. Authors' contributions Faiza Naeem and Sana Noreen: conceptualization, formal analysis, supervision, validation, reviewing, and editing; Hazeefa Sultan: formal analysis, software, validation, writing original draft; Patrick Maduabuchi Aja: conceptualization, software, formal analysis. Funding No Funding. Data availability No datasets were generated or analysed during the current study. Declarations Ethical approval and consent to participate The study was approved by the Institute Research Ethics Board (IREB), University of Lahore, Lahore, Pakistan (UOL/IREB/25/09/0008). All procedures performed in studies involving human participants were conducted in accordance with the ethical standards of the institutional research committee and in compliance with the 1964 Declaration of Helsinki and its subsequent amendments. This trial is also registered at ClinicalTrials.gov ( NCT07127055 ) as of August 8, 2025 http://clinicaltrials.gov/study/NCT07127055 . Consent for publication This manuscript does not contain any person’s data (such as names, images, or other identifying information). Therefore, consent for publication is not applicable. Competing interests The authors declare no competing interests. Footnotes Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. 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