Abstract Chronic inflammatory bowel diseases (IBD), including Crohn’s disease and ulcerative colitis, are associated with oxidative stress that contributes to persistent intestinal inflammation. This study evaluated the effects of an IBD-specific diet after two months of intake on oxidative, antioxidant, and inflammatory biomarkers in patients with IBD. The results demonstrated a significant reduction in oxidative stress markers (malondialdehyde and hydroperoxides) and inflammatory parameters (C-reactive protein and fecal calprotectin), along with an increase in antioxidant enzyme activities (catalase and superoxide dismutase). These beneficial effects were consistent across different patient profiles. Overall, this dietary intervention appears to be a promising nutritional approach for reducing oxidative stress and inflammation in patients with IBD.

Keywords: IBD specific diet, Oxidative stress, Intestinal inflammation, Fecal calprotectin

Citation:  Zoubida, S-M., Sidi-Mohammed, Y., Khadidja, T., Youssouf, K., Djihane, B., Naoual, L.M., Nouha, B., and Khadidja, B. 2026. A nutritional approach to modulating inflammatory activity in patients with inflammatory bowel disease. Natural and Life Sciences Communications. 25(4): e2026079.

Graphical Abstract:

INTRODUCTION

Inflammatory bowel diseases (IBD), a chronic diseases that cause inflammation of the digestive tract, and includes Crohn’s disease (CD) and ulcerative colitis (UC), which results abdominal pain, diarrhea, fatigue, and prevalent nutritional deficiencies (Muzammil et al., 2023). Pharmacological therapies aim to reduce inflammatory activity and inducing remission, therapeutic benefits may decline with prolonged use, with efficacy frequently compromised by side effects and partial symptom relief. Consequently, improving long-term outcomes in IBD requires an integrated therapeutic strategy that extends beyond conventional medication (Erzin et al., 2008; Torres et al., 2015).

Dietary factors are now acknowledged as central modulators of disease activity and patient well being in IBD. At the molecular level, inflammatory bowel diseases are characterized by a complex interplay between oxidative stress, immune dysregulation, and intestinal barrier dysfunction. Excessive production of reactive oxygen species (ROS) leads to lipid peroxidation, protein oxidation, and DNA damage, thereby amplifying inflammatory signaling pathways. Concurrently, dysregulated immune responses result in increased production of pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β), which sustain chronic inflammation. Alterations in gut microbiota composition further exacerbate this process by disrupting intestinal homeostasis and promoting mucosal damage. Together, these mechanisms contribute to the persistence and progression of intestinal inflammation in IBD (Zuo and Ng, 2018).

Nutrition influence intestinal inflammation, gut microbiota composition, regulation of immune responses, mucosal integrity, oxidative stress, and nutrient bioavailability, all of which can affect both the clinical course and quality of life (Shimoyama et al., 2023; Manski et al., 2024; Dhaliwal et al., 2025). Dietary interventions have been explored not only for symptom management but also for induction and maintenance of remission, although consensus on specific nutritional recommendations remains an ongoing area of research (Nieva et al., 2024; Ananthakrishnan et al., 2025). Evidence supports that diets rich in fresh fruits and vegetables, fiber, monounsaturated fats, and lean proteins may be associated with improved gut microbial diversity and reduced systemic inflammation, whereas Western style diets high in refined carbohydrates, saturated fats and ultra processed foods are linked to heightened inflammatory risk and poorer outcomes (Ananthakrishnan et al., 2025).

Despite the recognized importance of nutrition, many traditional approaches such as restrictive elimination diets or untargeted supplementation carry the risk of worsening nutritional imbalances and failing to meet individual metabolic and immune needs. (Reznikov and Suskind, 2023; Istratescu et al., 2024). Against this backdrop the development of an IBD-specific diet represents an innovative advancement in precision nutrition for the management of inflammatory bowel disease. Such dietary approaches are increasingly designed through close collaboration between nutritionists and gastroenterologists, with the aim of targeting key pathophysiological mechanisms of IBD, including chronic inflammation, oxidative stress, intestinal barrier dysfunction, and gut microbiota imbalance (Lewis and Abreu, 2017; Levine et al., 2020). Fruits and vegetables provide a rich source of polyphenols, vitamins, and dietary fibers that contribute to the reduction of oxidative stress and modulation of inflammatory pathways, while also supporting microbial diversity and short-chain fatty acid production in the gut (Zuo and Ng, 2018; Ananthakrishnan et al., 2025). The inclusion of seeds, which are rich in unsaturated fatty acids, fiber, and bioactive compounds, further enhances the anti-inflammatory potential of the formulation and may contribute to immune regulation and intestinal homeostasis (Calder, 2020). Clinical studies have demonstrated the beneficial effects of curcumin supplementation in both Crohn’s disease and ulcerative colitis, particularly as an adjunct to conventional therapy (Hanai et al., 2006; Coelho et al., 2020).

Probiotic-containing foods have been associated with improved intestinal inflammation control and symptom relief in IBD patients, particularly when included as part of a structured dietary intervention (Derwa et al., 2017; Sanders et al., 2019).

Importantly, the smoothie-based format ensures a palatable texture and improved digestibility, addressing common challenges faced by IBD patients such as reduced appetite, gastrointestinal discomfort, and intolerance to solid foods during active disease phases. Collectively, these characteristics support the rationale that an IBD-specific therapeutic smoothie can serve as a practical, patient-centered nutritional strategy that delivers multifaceted biological benefits while being tailored to the physiological and clinical needs of individuals with IBD.

MATERIALS AND METHODS

Patients, study period, and questionnaire development

This analytical longitudinal study involved a cohort of 30 patients (14 females and 16 males), aged 18 to 73 years, diagnosed with inflammatory bowel disease (IBD). The study assessed variables including age, sex, type of IBD, level of physical activity, psychological stress, dietary adherence, and weight loss, while all patients strictly adhered to their prescribed medication and dietary recommendations.

The sample size was determined based on the exploratory nature of the study and the feasibility of patient recruitment during the study period. Due to the innovative character of the nutritional intervention and the lack of prior data regarding the expected effect size and variability of the main outcome measures, a formal a priori power calculation was not feasible. Methodological guidelines indicate that pilot and exploratory longitudinal studies do not necessarily require formal sample size calculations when the primary aim is to generate preliminary data and estimate variability rather than to conduct hypothesis-confirmatory testing. In this context, a cohort of 30 patients was considered adequate to explore trends, assess feasibility and adherence, and perform within-subject comparisons over time, thereby increasing statistical efficiency despite the limited sample size (Lancaster et al., 2004; Leon et al., 2011; Whitehead et al., 2016).

A novel therapeutic smoothie, developed as a complementary nutritional intervention within the framework of a specific diet for inflammatory bowel diseases (IBD), was administered at a dose of 200 mL per day for two months. In parallel, patients were advised to follow a balanced diet rich in fruits and vegetables, with reduced intake of ultra-processed foods, sugar-sweetened beverages, and refined sugars, and a moderate caloric intake, in order to support gut health and mitigate treatment-related gastrointestinal side effects.

All participants completed a structured and detailed questionnaire. The first section collected sociodemographic information (age, sex, marital status), while the second section addressed clinical characteristics, including IBD type, current treatments, and dietary regimen.

The study was conducted in accordance with the principles of the Declaration of Helsinki and was approved by the Clinical Trial Ethics Committee of the University Hospital Center “Tedjini Damerdji”, Tlemcen, Algeria (Approval No. 171.FM.UABB.24). Written informed consent was obtained from all participants prior to inclusion in the study.

Inclusion criteria

Our cohort consists of patients with inflammatory bowel disease (IBD) who have been approved to take part in the study, are free of other inflammatory conditions, and do not have any food allergies or intolerances to IBD-specific diet components or prescription drugs.

Exclusion criteria

For this study, the exclusion criteria were as follows:

•      Other gastrointestinal diseases: Patients diagnosed with other gastrointestinal conditions such as irritable bowel syndrome (IBS), celiac disease, or acute intestinal infections.

•      Severe chronic diseases: Presence of uncontrolled severe chronic illnesses such as diabetes, renal or hepatic failure, or serious cardiovascular diseases.

•      Food allergies or intolerances: Severe allergies or intolerances to any components of IBD-specific diet or the prescribed diet.

•      Refusal to participate: Patients who decline to participate in the study.

Nutritional composition

Nutritional analysis of the IBD-specific diet was performed using the CIQUAL (2017) food composition database, which was employed to estimate the macro- and micronutrient content of each ingredient based on standardized values per 100 g. This included energy, macronutrients (carbohydrates, proteins, fats), and key micronutrients such as vitamin C, beta-carotene, iron, and magnesium. These estimates confirmed the high nutritional density of the smoothie and its potential relevance for correcting common deficiencies in IBD patients.

Preparation method of the IBD-Specific diet (smoothie form)

The IBD-specific diet was prepared in the form of a smoothie using standardized household processing methods. 100 g of beetroot was boiled until tender, while 100 g of pumpkin was steamed to preserve its texture and nutrient content. Separately, 5 g of flaxseeds were mixed with plain fermented yogurt and allowed to hydrate for several minutes. A ripe banana was peeled and cut into small pieces. All prepared ingredients were then combined, and 5 g of turmeric powder along with three teaspoons of date extract were added. The mixture was blended until a homogeneous consistency was obtained and consumed immediately after preparation.

Final mixing

All ingredients (cooked beetroot, steamed pumpkin, flaxseeds in yogurt, turmeric, date extract, and banana) were added to a blender. The mixture was blended until a smooth and homogeneous texture was obtained. If necessary, approximately one and a half glasses of water were added to adjust the smoothie’s consistency.

Blood sampling and lysate preparation

Blood samples were collected in the morning from the antecubital vein, using heparinized tubes. The heparinized blood was then centrifuged at 2,200 × g for 10 minutes at room temperature to separate plasma. Plasma aliquots were stored at -80°C until analysis. The remaining pellet was washed with physiological saline, and erythrocytes were lysed by adding chilled distilled water. The lysate was subsequently centrifuged at 4,000 rpm for 10 minutes to remove cellular debris. The resulting lysate was collected and stored at -80°C until further analysis.

Determination of oxidant/antioxidant status parameters

Oxidative stress, characterized by a disruption in the equilibrium between endogenous antioxidant defence systems and reactive oxygen species (ROS) generation, represents a pivotal pathophysiological mechanism underlying numerous clinical conditions. To comprehensively assess the oxidant/antioxidant balance in blood specimens, multiple biochemical parameters were systematically evaluated.

Measurement of malondialdehyde (MDA) levels

Malondialdehyde (MDA) concentrations were quantified as a principal biomarker of lipid peroxidation and oxidative cellular damage (Zheng et al., 2024). In conjunction with MDA assessment, hydroperoxide levels were determined to provide complementary information regarding the oxidant status (Zheng et al., 2024). These parameters were measured utilizing specific analytical methods employing thiobarbituric acid and 2,4-dinitrophenyl hydrazine reactions, respectively (MAK085-1KT and MAK094-1KT, Sigma-Aldrich kit; St. Louis, MO, USA).

Measurement of catalase activity

Catalase enzymatic activity was assessed through spectrophotometric quantification of its capacity to decompose hydrogen peroxide, a deleterious ROS, into water and molecular oxygen (Baudin, 2020). The assay was performed by monitoring the rate of hydrogen peroxide (H₂O₂, 35 mM) degradation at 240 nm wavelength using a commercial catalase activity kit (CAT100-1KT, Sigma-Aldrich) (Hadwan, 2018).

Measurement of superoxide dismutase (SOD) activity

Superoxide dismutase (SOD) activity was determined following the established methodology described by Weydert and Cullen (2010), which measures the enzyme's capacity to neutralize superoxide radicals.

C- Measurement of C-reactive protein (CRP)

Serum C-reactive protein (CRP) concentrations were quantified using enzyme-linked immunosorbent assay (ELISA) methodology. Blood samples were collected from participants before initiating the intervention and following the two-month period of IBD-specific supplementation to evaluate changes in systemic inflammatory status.

Measurement of fecal calprotectin levels

Fecal calprotectin serves as a highly specific non-invasive biomarker for detecting and monitoring intestinal mucosal inflammation, particularly in the context of inflammatory bowel diseases (IBD). Calprotectin concentrations in stool specimens were quantified employing the enzyme-linked immunosorbent assay (ELISA) technique, which represents the gold standard methodology for this parameter.

Both inflammatory biomarkers, C-reactive protein (CRP) and fecal calprotectin, were analysed at the laboratory facilities of EPH Maâlem Lahcen Ghazaouet under the direct supervision of Dr. Oudjdi, a gastroenterology specialist, and his qualified technical team.

 Statistical analysis

Data were processed using Minitab software to calculate means, standard deviations, and to visualize results through histograms. Analysis of variance (ANOVA) was employed to evaluate the effect of IBD-specific diet smoothie consumption on biomarkers (MDA, hydroperoxides, catalase, SOD, CRP, and fecal calprotectin), as well as to assess the influence of anthropometric factors, dietary variables, and the type of inflammatory bowel disease. Results are presented as means ± standard deviations, with a statistical significance threshold set at P < 0.05. Additional analyses were performed using GraphPad Prism version 8.

RESULTS

Changes in oxidative parameters

Plasma and erythrocyte malondialdehyde (MDA)

Prior to IBD-specific diet supplementation, plasma MDA concentrations demonstrated elevated baseline values (7,930 ± 2,917 μmol/L), indicative of substantial lipid peroxidation activity. Following a two-month intervention period, plasma MDA levels exhibited a statistically significant reduction to 2,890 ± 1,422 μmol/L (P = 0.0001) (Figure 1 a1).

Similarly, erythrocyte MDA concentrations showed a pronounced decrease from pre-intervention levels of 6,636.27 ± 765.23 μmol/L to post-intervention values of 3,143.93 ± 2,347.91 μmol/L (P = 0.0001), demonstrating a significant amelioration of intracellular oxidative stress burden (Figure 1 b1).

Figure 1. Plasma and erythrocyte malondialdehyde (MDA) levels in patients with inflammatory bowel disease (IBD) before and after two months of IBD BOOST smoothie consumption (n=30).

Plasma and erythrocyte hydroperoxides

Plasma hydroperoxide concentrations demonstrated a statistically significant decline following intervention, decreasing from baseline values of 942.9 ± 412.7 μmol/L to 392 ± 266.4 μmol/L (P = 0.0001) (Figure 2 a2).

Erythrocyte hydroperoxide levels exhibited a comparable pattern of reduction, with concentrations significantly decreasing from pre-intervention levels of 1,120 ± 743 μmol/L to post-intervention values of 491.3 ± 245.2 μmol/L (P = 0.0001) (Figure 2 b2).

Figure 2. Plasma and erythrocyte hydroperoxide levels in patients with inflammatory bowel disease (IBD) before and after two months of IBD BOOST smoothie consumption (n=30).

Changes in antioxidant enzyme activities

Plasma and erythrocyte catalase

Regarding antioxidant enzyme activities, the enhancement of plasma catalase represents a particularly significant finding.

Plasma catalase activity demonstrated a significant enhancement following supplementation, increasing from baseline levels of 0.0045 ± 0.0003 μmol/L to 0.0053 ± 0.0004 μmol/L (P = 0.0001) (Figure 3 a3).

Erythrocyte catalase activity showed a corresponding improvement, with levels rising from 0.0026 ± 0.0005 μmol/L to 0.0035 ± 0.0007 μmol/L (P = 0.0001) (Figure 3 b3).

Figure 3. Plasma and erythrocyte catalase activity in patients with inflammatory bowel disease (IBD) before and after two months of IBD BOOST smoothie consumption (n=30).

Plasma and erythrocyte superoxide dismutase (SOD)

Plasma SOD activity, which catalyzes the neutralization of superoxide radicals, exhibited a significant increase from pre-intervention levels of 0.2241 ± 0.0602 mM/min/mL to post-intervention values of 0.4502 ± 0.0881 mM/min/mL (P = 0.0001) (Figure 4 a4).

Erythrocyte SOD activity demonstrated a similar pattern of enhancement, increasing from 0.1488 ± 0.0870 mM/min/mL to 0.2397 ± 0.0619 mM/min/mL (P = 0.002) (Figure 4 b4).

Figure 4. Plasma and erythrocyte superoxide dismutase (SOD) activity in patients with inflammatory bowel disease (IBD) before and after two months of IBD BOOST smoothie consumption (n=30).

Changes in inflammatory markers

C-reactive protein (CRP)

IBD-specific diet supplementation resulted in a statistically significant reduction in CRP concentrations, with levels decreasing from 39.02 ± 25.64 mg/L to 4.69 ± 2.85 mg/L (P = 0.0001) (Figure 5). This substantial reduction demonstrates marked attenuation of systemic inflammatory responses in the study population. These findings suggest that IBD-specific diet exerts broad anti-inflammatory effects in IBD patients, potentially through modulation of the systemic immune microenvironment.

Figure 5. C-reactive protein (CRP) levels in patients with inflammatory bowel disease (IBD) before and after two months of IBD-specific diet consumption (n=30).

Fecal calprotectin (FC)

Fecal calprotectin concentrations exhibited a significant decrease following intervention, with mean levels declining from 465.38 ± 264.87 μg/g to 91.32 ± 48.60 μg/g post-treatment (P = 0.0001) (Figure 6). This pronounced reduction indicates substantial amelioration of localized intestinal inflammation, supporting the hypothesis that IBD-specific diet facilitates restoration of mucosal integrity and attenuates leukocyte infiltration within the intestinal mucosa.

Figure 6. Fecal calprotectin levels in patients with inflammatory bowel disease (IBD) before and after two months of IBD-specific diet consumption (n=30).

Influence of anthropometric, dietary factors, and IBD type

No statistically significant differences were observed in mean CRP concentrations (Table 1) or fecal calprotectin levels (Table 2) when stratified by anthropometric variables, dietary factors, or IBD subtype. These findings suggest that IBD-specific diet demonstrates consistent therapeutic efficacy independent of these patient-specific characteristics, indicating a generalized anti-inflammatory effect across diverse patient populations.

Table 1: Effect of anthropometric parameters, dietary factors, and type of IBD on C-reactive protein (CRP).

Table 2. Effect of anthropometric parameters, dietary factors, and type of IBD on fecal calprotectin (FC).

DISCUSSION

Inflammatory bowel diseases (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), are characterized by persistent intestinal inflammation caused by an inappropriate immune response (Rahmouni et al., 2016). In this context, oxidative stress plays a central role in the pathophysiology of these diseases (Bali et al., 2025; Daoudi et al., 2026; Rahmoun et al., 2026), and nutritional interventions may provide complementary therapeutic approaches (Arnone et al., 2024). The aim of this study was to evaluate the effect of the IBD-specific diet smoothie on oxidative stress markers, antioxidant enzymes, and biomarkers of intestinal inflammation.

The observed significant reduction in plasma MDA levels indicates a substantial decrease in systemic oxidative stress. MDA, as a terminal biomarker of lipid peroxidation, is often elevated in inflammatory diseases (Cordiano et al., 2023). Similar findings were reported by Hong and Piao (2018) with quercetin aglycone supplementation. Concurrently, the decrease in erythrocyte MDA levels may be attributed to the combined antioxidant effects of IBD-specific diet ingredients, such as beetroot, which is rich in protective phenolic compounds (Singh et al., 2019). In addition to general phenolic compounds, beetroot contains specific bioactive pigments known as betalains, which exhibit potent anti-inflammatory and antioxidant properties. Betalains have been shown to inhibit key pro-inflammatory signaling pathways, including NF-κB activation, thereby reducing the expression of inflammatory mediators. Furthermore, these compounds contribute to the neutralization of reactive oxygen species, reinforcing cellular antioxidant defenses and protecting intestinal tissues from oxidative damage (Gengatharan et al., 2015), this dual reduction in both plasma and cellular compartments suggests a comprehensive anti-oxidative effect of the intervention.

The significant decline in plasma hydroperoxide concentrations further supports these findings, as these compounds are early products of lipid peroxidation and are generally unstable (Bonnefont-Rousselot, 2020). Their decrease reflects attenuation of oxidative stress induced by inflammation. Similarly, the reduction in erythrocyte hydroperoxide levels indicates improved intracellular redox status following product consumption, demonstrating that the beneficial effects extend beyond the systemic circulation to the cellular level (Lobo et al., 2010).

The high dietary fiber content of beetroot and pumpkin may play a crucial role in modulating gut microbiota composition. Fermentation of dietary fibers by intestinal bacteria leads to the production of short-chain fatty acids (SCFAs), such as butyrate, which exert anti-inflammatory effects, enhance intestinal barrier integrity, and regulate immune responses. This mechanism may partly explain the observed reduction in fecal calprotectin levels (Makki et al., 2018).

The observed increase suggests stimulation of endogenous antioxidant defenses by the bioactive compounds in IBD-specific diet, notably curcumin (Gorabi et al., 2021). The parallel increase in erythrocyte catalase activity supports the hypothesis of a systemic effect of the smoothie on intracellular antioxidant enzymes, indicating that the intervention successfully enhances the body's intrinsic protective mechanisms.

The significant enhancement in plasma SOD activity represents another crucial aspect of the antioxidant response. This improvement suggests enhanced management of reactive oxygen species (ROS), potentially limiting tissue damage (Bowler and Crapo, 2002).

This result aligns with findings by Singh et al. (2019), who demonstrated the effect of polyphenols such as EGCG (Epigallocatechin-3-gallate) on SOD upregulation. The corresponding increase in erythrocyte SOD activity confirms the stimulatory effect of IBD-specific diet on intracellular antioxidant defences, reinforcing the comprehensive nature of the intervention's protective effects.

The dramatic reduction in CRP levels provides compelling evidence of the anti-inflammatory potential of IBD-specific diet. CRP is an acute-phase protein synthesized by the liver in response to inflammation, driven by pro-inflammatory cytokines such as IL-6, IL-1β, and TNF-α, with serum CRP levels rising rapidly during systemic inflammation. In IBD patients, CRP serves as an indirect marker of inflammatory activity, particularly in Crohn's disease (Marlow et al., 2013). However, it is important to acknowledge that CRP is not a disease-specific marker for IBD, as patients may present with normal CRP despite active disease, particularly in ulcerative colitis. Nevertheless, it remains a valuable indicator for monitoring overall inflammatory evolution (Savarino et al., 2022).

The substantial decrease in fecal calprotectin levels provides even more specific evidence of the intervention's anti-inflammatory effects at the intestinal level. Fecal calprotectin is a neutrophil-derived protein excreted in stool in response to intestinal inflammation and is currently considered a preferred biomarker in IBD due to its specificity for mucosal inflammation (Boschetti, 2021). Calprotectin demonstrates superior reliability compared to CRP for detecting active intestinal inflammation, even in the absence of clinical symptoms or when CRP levels remain normal. This characteristic makes it particularly useful for both evaluating therapeutic response and predicting disease relapses (Kapel et al., 2023)., in addition to these mechanisms, micronutrient composition may also contribute to the observed anti-inflammatory effects. Vitamin C reduces oxidative stress by scavenging free radicals and regenerating other antioxidants. Additionally, emerging evidence suggests that vitamin C deficiency is associated with increased inflammatory activity in IBD patients, and its adequate intake may help reduce biomarkers such as calprotectin. (Gordon et al., 2022).

The marked reduction observed in this study therefore suggests that IBD-specific diet effectively targets the underlying intestinal inflammatory processes characteristic of IBD.

An important finding of this study is the absence of significant differences in treatment response based on anthropometric variables, dietary factors, or IBD subtype. This observation suggests that IBD-specific demonstrates consistent therapeutic efficacy across diverse patient populations, indicating a robust and generalizable anti-inflammatory effect. The lack of variation in CRP and fecal calprotectin responses according to these patient characteristics implies that the intervention's beneficial effects are not dependent on individual patient profiles or disease phenotypes. This finding is particularly relevant for clinical application, as it suggests that IBD-specific diet may be equally effective regardless of patient age, sex, physical activity levels, dietary adherence, weight loss status, or whether patients have Crohn's disease or ulcerative colitis. Such consistency in therapeutic response across different patient subgroups supports the potential for broad clinical implementation without the need for extensive patient stratification or personalized dosing protocols.

The consistency of these improvements across multiple biomarkers, encompassing both oxidative stress parameters and inflammatory indicators, combined with the uniform response across different patient characteristics, suggests that IBD-specific diet exerts multifaceted therapeutic effects through fundamental biological pathways. The intervention appears to simultaneously enhance antioxidant defences while reducing both systemic and local inflammatory responses, potentially addressing multiple pathophysiological mechanisms underlying IBD progression in a manner that transcends individual patient variability.

CONCLUSION

This study highlights the critical role of oxidative stress in the pathophysiology of inflammatory bowel diseases (IBD), such as Crohn's disease and ulcerative colitis, and demonstrates that enhancing antioxidant defences represents a promising therapeutic strategy. The objective was to provide a specific dietary intervention, developed in collaboration with nutrition experts and gastroenterologists, rich in essential nutrients that are often deficient in these patients, with anti-inflammatory properties and easy digestibility.

After two months of IBD-specific diet consumption, patients exhibited significant reductions in oxidative stress markers, plasma and erythrocyte malondialdehyde (MDA) and hydroperoxides, alongside increases in antioxidant enzyme levels, notably superoxide dismutase (SOD) and catalase in both plasma and erythrocytes. Additionally, inflammatory markers showed remarkable improvements, with C-reactive protein (CRP) levels decreasing dramatically and fecal calprotectin concentrations declining substantially, indicating significant reduction in both systemic and intestinal inflammation. These findings demonstrate that the antioxidant-rich composition of IBD-specific diet contributed to improved antioxidant defences and anti-inflammatory effects, representing an effective therapeutic approach for IBD.

Importantly, these beneficial effects were consistent across different patient characteristics, including age, sex, IBD type, and lifestyle factors, suggesting broad clinical applicability. This project offers an affordable and beneficial nutritional solution in the form of a smoothie designed to alleviate inflammatory symptoms while supplying essential nutrients. Although non-pharmacological, this smoothie could complement medical treatments, enhance patients' quality of life, and help restore nutritional balance.

ACKNOWLEDGEMENTS

The authors would like to sincerely thank the volunteer patients with inflammatory bowel disease for their valuable participation in this study. They also thank the medical and paramedical staff of the hospitals of Nedroma and Ghazaouet, as well as the University Hospital Center of Tlemcen, for their cooperation and support during the conduct of this work.

AUTHOR CONTRIBUTIONS

Soulem-Mami Zoubida: Conceptualization (Lead), Data Curation (Lead), Software (Lead), Validation (Lead), Writing – Original Draft (Lead); Yazit Sidi-Mohammed: Formal Analysis (Equal), Validation (Equal), Visualization (Equal), Writing – Review & Editing (Equal); Taleb Khadidja: Data Curation (Equal), Formal Analysis (Equal), Software (Equal), Supervision (Equal), Validation (Equal), Visualization (Equal), Writing – Review & Editing (Equal); Kachekouche Youssouf: Data Curation (Equal), Formal Analysis (Equal), Validation (Equal); Bali Djihane: Data Curation (Equal); Formal Analysis (Equal); Validation (Equal); Writing – Review & Editing (Supporting); Oudjdi Nawel: Investigation (Lead), Visualization (Equal), Supervision (Lead), Validation (Equal); Benghalem Nouha: Investigation (Equal), Supervision (Equal), Validation (sopporting), Visualization (Equal); Bouchentouf Khadidja: Data Curation (supporting), Formal Analysis (Equal), Validation (Equal), Writing – Review & Editing (Supporting).

CONFLICT OF INTEREST

The authors declare that they have no conflicts of interest.

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