Dietary patterns and prevalence of irritable bowel syndrome in Iranian adults

Metabolic biomarkers in irritable bowel syndrome diagnosis

Irritable bowel syndrome (IBS) is a chronic gastrointestinal (GI) disorder characterized by altered bowel habits and abdominal discomfort during defecation. It significantly impacts life quality and work productivity for those affected. Global data suggests a slightly higher prevalence in females than in males. Today, unambiguous diagnosis of IBS remains challenging due to the absence of a specific biochemical, histopathological, or radiological test. Current diagnosis relies heavily on thorough symptom evaluation. Efforts by the Rome committees have established standardized diagnostic criteria (Rome I-IV), improving consistency and clinical applicability. Recent studies in this framework, seem to have successfully employed metabolomics techniques to identify distinct metabolite profiles in breath and stool samples of IBS patients, differentiating them from healthy controls and those with other functional GI disorders, such as inflammatory bowel disease (IBD). Building on this success, researchers are investigating the presence of similar metabolites in easily accessible biofluids such as urine, potentially offering a less invasive diagnostic approach. Accordingly, this review focuses on key metabolites specifically detected in IBS patients' biological specimens, with a focus on urinary metabolites, using various methods, particularly mass spectrometry (MS)-based techniques, including gas chromatography-MS (GC-MS), liquid chromatography-tandem MS (LC-MS/MS), and capillary electrophoresis-MS (CE-MS) metabolomics assays. These findings may make provision for a new set of non-invasive biomarkers for IBS diagnosis and management.

A systematic review and meta-analysis of diet and nutrient intake in adults with irritable bowel syndrome

BACKGROUND

Numerous individual and environmental factors including diet may play an important role in the pathophysiology of irritable bowel syndrome (IBS). It is unclear to what degree dietary intake is affected in individuals with IBS. We aimed to perform a systematic review and meta-analysis to summarize dietary intake of adults with IBS and to compare dietary intake between adults with IBS and non-IBS controls.

METHODS

Ovid MEDLINE, Embase, Cochrane, CINAHL, and Scopus were searched through February 2023 for clinical trials and observational studies measuring usual diet in adults with IBS. Pooled weighted averages were estimated for total energy, macronutrient, and micronutrient data. Mean differences (MD) in nutrient intake were estimated for adults with IBS versus non-IBS controls using a random effects model. Heterogeneity was assessed by the inconsistency index (I2).

KEY RESULTS

Sixty-three full-text articles were included in the review of which 29 studies included both IBS and control subjects. Nutrients not meeting the recommended intake level for any dietary reference values in the IBS population were fiber and vitamin D. Meta-regression by female proportion was positively correlated with total fat intake and negatively correlated with carbohydrate intake. Comparisons between participants with IBS and controls showed significantly lower fiber intake in participants with IBS with high heterogeneity (MD: -1.8; 95% CI: -3.0, -0.6; I2 = 85%).

CONCLUSIONS AND INFERENCES

This review suggests that fiber and vitamin D intake is suboptimal in IBS; however, overall dietary intake does not appear to be comprised. Causes and consequences of reduced fiber in IBS deserve further study. Results of this systematic review and meta-analysis suggest that fiber and vitamin D intake is suboptimal in IBS. However, overall intake of other macro- and micronutrients does not appear to be compromised. Causes and consequences of reduced fiber and Vitamin D intake in IBS deserve further study.

Dietary intake of phytochemicals in association with irritable bowel syndrome in adults

BACKGROUND & AIM

There is limited data regarding the association between phytochemical-rich diets and irritable bowel syndrome (IBS). The current study aimed to cross-sectionally evaluate the association of dietary phytochemical index (DPI) with the odds and severity of IBS.

METHODS

In this study, which included 3362 Iranian healthcare staffs, a dish-based semi-quantitative food frequency questionnaire (DS-FFQ) was utilized to collect dietary information. The DPI was defined as the daily percentage of calories consumed from phytochemical-rich foods. The IBS assessment was performed using a revised Iranian version of the Rome III questionnaire. We applied the restricted cubic spline (RCS) to detect the possible non-linear dependency of the relationship between DPI and the odds of IBS.

RESULTS

The mean age, Body Mass Index (BMI), and DPI scores of the participants were 36.29 ± 7.8 years, 24.90 ± 3.8 kg/m2, and 16.07 ± 9.01, respectively. After adjusting for possible confounders, no significant association was observed between DPI and odds of IBS in the whole study population or in gender- and BMI-stratified analyses. We found a significant inverse association between DPI and IBS severity in the study population (OR: 0.70; 95% CI: 0.51-0.98). Concerning gender, such an association was only found in women (OR: 0.65; 95% CI: 0.44-0.96). However, there was no significant relationship between DPI and IBS severity in BMI subgroups. In addition, we found no meaningful relationship between DPI and IBS subtypes. The RCS model showed that there is no non-linear relationship between DPI classification and IBS (non-linear test, χ2 = 1.14, Pnon-linearity = 0.513).

CONCLUSIONS

Higher phytochemical intake was associated with reduced IBS severity, particularly in women. Further prospective studies are required to confirm these findings.

The dietary patterns derived by reduced-rank regression in association with Framingham risk score and lower DASH score in Hoveyzeh cohort study

The relationship between dietary patterns (DPs) and cardiovascular disease (CVD) has been the subject of much research, but given the significance of this disease, studying the factors affecting it through different methodological considerations is of utmost importance. This study aimed to investigate the association between the four dietary patterns (DPs) derived from reduced-rank regression (RRR) and the risk of CVD predicted by the Framingham Risk Score (FRS) in the Arab residence of Khuzestan, Iran. Furthermore, the predefined Dietary Approaches to Stop Hypertension (DASH) would be used as a comparative model to assess the validity of the extracted DPs. In this cross-sectional study, 5799 individuals aged 35-70 without a CVD diagnosis were selected among the participants of the Hoveyzeh cohort study (HCS). The Risk of CVD was assessed using the FRS model. A semi-quantitative food frequency questionnaire evaluated dietary intake. Four DPs were derived using RRR with 28 food groups as predictors and total protein (g/d), fiber(g/d), fat(g/d), and magnesium intake (mg/d) as response variables. Multinomial and binary logistic regression were used to assess the relationship of DPs with intermediate (10-20%) and high (> 20%) levels of FRS and lower DASH scores (< 4.5), respectively. Four primary DPs were derived, which explained 89.10 of the total explained variance in participants' dietary intake. Multinomial regression was applied between FRS (10-20%) and (> 20%) across quartiles of four identified DPs. After adjustment for potential confounders, higher tendency to 1st and 2nd DPs in Model 1, OR = 4.67 (95% CI 3.65; 6.01), OR = 1.42 (95% CI 1.13; 1.79) were presented accordingly. The 1st DP, characterized by higher intake of refined grains and lower intake of vegetables oil, sugar, mayonnaise and artificial juices, the 2nd DP characterized by higher intake of hydrogenated fat and lower consumption of tomato sauce and soft drink was associated with greater odds of CVD with the intermediate level of FRS. However, higher adherence to the 3rd DP, characterized by higher intake of fruits, vegetables and legumes and lower intake of fish, egg, red meat, processed meat, mayonnaise, sugar and artificial juices, the 4th DP characterized by higher intake of coffee, nuts and lower intake of sugar, mayonnaise and artificial juices was associated with a lower risk of FRS. Moreover, lower DASH score considered in binary logistic regression across quartiles of four identified dietary patterns. 1st and 2nd DPs were directly related to lower DASH scores, while 3rd and 4th DPs had high comparability with the DASH diet and inversely contributed to the lower DASH score. Total DASH score was significantly correlated to four derived DPs. Our findings confirm the current knowledge regarding the beneficial effects of healthy plant-based DPs and the avoidance of high-fat and processed foods to prevent CVD.

Diet-microbiota interaction in irritable bowel syndrome: looking beyond the low-FODMAP approach

BACKGROUND

Diet is one of the main modulators of the gut microbiota, and dietary patterns are decisive for gut-microbiota-related diseases, including irritable bowel syndrome (IBS). The low-FODMAP diet (LFD) is commonly used to treat IBS, but its long-term effects on microbiota, symptoms and quality of life (QoL) are unclear. Alternative dietary strategies promoting beneficial gut microbiota, combined with reduced symptoms and improved QoL, are therefore of interest.

AIMS

To review current evidence on the diet-microbiota-interaction as a modulator of IBS pathophysiology, and dietary management of IBS, with particular emphasis on strategies targeting the gut microbiota, beyond the LFD.

METHODS

Literature was identified through PubMed-searches with relevant keywords.

RESULTS

Dietary patterns with a low intake of processed foods and a high intake of plants, such as the Mediterranean diet, promote gut microbiota associated with beneficial health outcomes. In contrast, Western diets with a high intake of ultra-processed foods promote a microbiota associated with disease, including IBS. Increasing evidence points towards dietary strategies consistent with the Mediterranean diet being equal to the LFD in alleviating IBS-symptoms and having a less negative impact on QoL. Timing of food intake is suggested as a gut microbiota modulator, but little is known about its effects on IBS.

CONCLUSIONS

Dietary recommendations in IBS should aim to target the gut microbiota by focusing on improved dietary quality, considering the impact on both IBS-symptoms and QoL. Increased intake of whole foods combined with a regular meal pattern and limitation of ultra-processed foods can be beneficial strategies beyond the LFD.

Significant Differences in Gut Microbiota Between Irritable Bowel Syndrome with Diarrhea and Healthy Controls in Southwest China

BACKGROUND

Irritable bowel syndrome (IBS) is a heterogeneous disease, which is closely related to environmental factors and gut microbiota.

OBJECTIVE

To study gut microbiota in IBS-D of Han nationality in Southwest China and explore its relationship with environmental factors.

METHODS

One hundred and twenty cases of IBS-D and 63 cases of HCs were recruited; baseline data such as age, height, and weight were collected. HAMA, HAMD, IBS-SSS, IBS-QOL, and laboratory tests were performed. Feces were collected for 16S rDNA sequencing. Then, the differences of gut microbiota were analyzed and looked for biomarkers of each. FAPROTAX was used to predict the functional differences of gut microbiota. Spearman analysis was conducted between the phylum level and environmental factor.

RESULTS

There were significant differences in daily life between IBS-D and HCs, especially in the spicy taste. The scores of HAMA and HAMD, urea, and transaminase in IBS-D were significantly higher than those of HCs. The richness of gut microbiota in IBS-D was significantly lower than that of HCs, as well as the beta diversity, but not diversity. The biomarkers of IBS-D were Prevotella, Clostridiales, and Roseburia, and the biomarkers of HCs were Veillonellaceae, Bacteroides coprocola, and Bifidobacteriales. The functions of gut microbiota in IBS-D were significantly different from HCs. Correlation analysis showed that multiple gut microbiota were closely related to HAMA, IBS-SSS, IBS-QOL, inflammatory indexes, and liver enzymes.

CONCLUSION

There are significant differences in richness of gut microbiota, flora structure, and flora function between IBS-D and HCs in Southwest China. These differences may be closely related to environmental factors such as eating habits, living habits, and mental and psychological factors.

CLINICAL TRIAL REGISTRATION

The trial was registered and approved in China Clinical Trial Registry (Registration No. ChiCTR2100045751).

Irritable bowel syndrome and its associated factors among Jordanian medical students: A cross-sectional study

Very scarce studies investigated the prevalence of irritable bowel syndrome (IBS) and its correlates in the Middle East, particularly in college students. We aimed to investigate the prevalence of IBS and its associated factors among Jordanian medical students. We conducted a cross-sectional study at 2 medical facilities in northern Jordan. We recruited 1135 medical students. Participants completed an anonymous questionnaire addressing sociodemographic, lifestyle, and clinical characteristics. An interview questionnaire was used to diagnose IBS according to the Rome III criteria. Comorbid anxiety and depression were diagnosed by using the Hospital Anxiety and Depression Scale. Of the 1135 completed questionnaires, 1094 (94%) had complete data. The prevalence of IBS in our sample was 30.9%. Binary logistic regression analysis of factors associated with IBS indicated having a family history of IBS as a strong predictor of the disease (odds ratio [OR]: 8.09; 95% confidence interval [CI]: 5.84-11.19). Students in the second and third years of their study had ORs of approximately 4 (95% CI: 2.20-6.54) and 3 (95% CI: 1.70-5.30) for suffering from IBS, respectively, compared with those in the first year (P = .001). Increased anxiety score (OR: 1.88; 95% CI: 1.30-2.71), poor sleep quality (OR: 1.76; 95% CI: 1.13-2.76), female sex (OR: 1.59; 95% CI: 1.14-2.20), and living in a school dormitory (OR: 1.35; 95% CI: 1.00-1.84) were significantly associated with IBS (P < .05). IBS is a highly prevalent disorder among Jordanian medical students, with several factors associated with its occurrence.

The relationship between meal regularity with Irritable Bowel Syndrome (IBS) in adults

BACKGROUND

The irregular meal pattern and meal-skipping might be related to irritable bowel syndrome (IBS), however, findings of previous investigations are contradictory. We aimed to examine the relation of meal regularity with IBS in Iranian adult population.

METHODS

Data on 4599 adults who worked in 50 different health centers were used in this cross-sectional study. Dietary habits were measured using a pretested questionnaire. IBS identification was performed through the use of a modified version of Rome III questionnaire.

RESULTS

IBS was prevalent among 18.6% of men and 24.1% of women. After adjustment for potential confounders, those with regular meal pattern, in comparison to those with irregular meals, had 40% lower odds for IBS (OR:0.60, 95%CI: 0.41-0.87). Individuals with regular meals had also 82 lower risk for IBS-Mixed, in comparison to those who had irregular meals (OR:0.18, 0.95%CI: 0.08-0.43). Stratified analysis by gender revealed that women with regular meals, compared with those who did not, had 44% lower risk for IBS (OR: 0.56, 0.95%CI: 0.34-0.91). Normal-weight individuals who had regular meal pattern, compared to those who did not, had 63% lower risks for IBS (OR:0.37, 95%CI: 0.22-0.64). Furthermore, subjects who had regular meal pattern had 53% lower risk for severe symptoms of IBS (OR:0.47, 95%CI: 0.30-0.71).

CONCLUSION

We found that participants with regular meal pattern had reduced odds of IBS, IBS-Mixed and the syndrome severity. Meal regularity was also linked to reduced IBS prevalence in women, and in normal-weight individuals. More prospective studies are needed to affirm these associations.

Dietary modulation of gut microbiota for the relief of irritable bowel syndrome

Irritable bowel syndrome (IBS) is a frequently diagnosed gastrointestinal (GI) disorder characterized by recurrent abdominal pain, bloating, and changes in the stool form or frequency without any structural changes and overt inflammation. It is not a life-threatening condition but causes a considerable level of discomfort and distress. Among the many pathophysiologic factors, such as altered GI motility, visceral hypersensitivity, and low-grade mucosal inflammation, as well as other immunologic, psychologic, and genetic factors, gut microbiota imbalance (dysbiosis), which is frequently found in IBS, has been highlighted as an etiology of IBS. Dysbiosis may affect gut mucosal homeostasis, immune function, metabolic regulation, and even visceral motor function. As diet is shown to play a fundamental role in the gut microbiota profile, this review discusses the influence of diet on IBS occurring through the modulation of gut microbiota. Based on previous studies, it appears that dietary modulation of the gut microbiota may be effective for the alleviation of IBS symptoms and, also an effective IBS management strategy based on the underlying mechanism; especially because, IBS currently has no specific treatment owing to its uncertain etiology.

A Comprehensive Review of Transaminitis and Irritable Bowel Syndrome

We observed in the literature that irritable bowel syndrome (IBS) may be linked to irregular parameters of the metabolic system (MS) and liver function. For that reason, we conducted this systematic review to comprehensively analyze the association of transaminitis (elevated alanine transaminase (ALT)) with IBS. This review was designed by following methods described in the Cochrane Handbook for Systematic Reviews of Interventions. Published peer-reviewed journal articles were included. Data were extracted based on study design, age, gender, author, date of publication or availability online, publication type, participants, gender (M/F), and types of IBS. Our electronic multiple databases yielded a total of 519 preliminary studies; we then removed duplicate studies and left with 326 studies. After reviewing the full text of these articles, a total of 83 studies were eliminated and lastly, three studies were selected for this systematic review for quantitative and qualitative analysis. All the enrolled subjects in included studies were diagnosed with IBS by the Rome II and III criteria and among these sub-jects, 50.4% had IBS-D, 13.8% had IBS-C, 30.3% had IBS-M, and 3.5% had IBS-U. The prevalence of elevated ALT with other liver enzymes (γ-GT levels and aspartate aminotransferase (AST)) in patients with irritable bowel syndrome whether their body mass index (BMI) was high or not (16.9% vs. 7.7%; p=0.015) and γ-GT (24.1% vs. 11.5%; p=0.037), Lee et al., 2016. The IBS-D subtype was seen more commonly in patients whose alcohol intake was significantly high however their study data showed no significant change in elevation of ALT. The upper limits normal values for serum liver enzymes were de-fined as 41 international per liter in males and 31 international units per liter in females for ALT. No significant relationships were observed between IBS status and elevated γ-GT (OR, 1.647; 95% CI, 0.784-3.461). The review study proposes a potential relation between elevated ALT levels, MS, and IBS, and this review might be the first review in IBS patients to observe the association of elevated ALT in the IBS population. Although further additional trials with a large sample size will be required to confirm these results. Furthermore, for assessing the efficacy of the manipulation of gut microbiota ran-domized controlled trials in a large population of IBS patients are needed to establish a causal-resultant relationship between IBS, MS, and liver damage.

The Association between Adherence to the MIND Diet and Irritable Bowel Syndrome

BACKGROUND AND AIMS

No earlier study examined the association between adherence to the MIND (Mediterranean-DASH Diet Intervention for Neurodegenerative Delay) diet and odds of irritable bowel syndrome (IBS). This study was conducted to examine the relationship between adherence to the MIND diet and odds of IBS among Iranian adults.

METHODS

In this cross-sectional study, dietary intakes of 3,362 adults were examined using a validated Dish-Based 106-item Semi-Quantitative Food Frequency Questionnaire (DS-FFQ). The MIND diet score was constructed based on participants' dietary intakes obtained from DS-FFQ. IBS was evaluated using a modified Persian version of the Rome III questionnaire.

RESULTS

Overall, 22.2% of the study population were affected by IBS (n = 748). We observed no significant relationship between adherence to the MIND diet and odds of IBS in the whole population (OR: 0.97; 95% CI: 0.71-1.31). By gender and BMI status, no significant association between adherence to the MIND diet and odds of IBS was seen. Also, no significant association was found between adherence to the MIND diet and IBS subtypes.

CONCLUSION

No significant association was found between adherence to the MIND diet and odds of IBS. Further studies are needed to examine the association between dietary patterns and IBS.

The association between dietary patterns with severity of coronary artery stenosis, serum leptin-to-adiponectin ratio, and some related risk factors in patients with coronary artery disease

Background

This research aimed to investigate the association between dietary patterns with severity of coronary artery stenosis, serum leptin-to-adiponectin ratio, and some related risk factors in patients with coronary artery disease referred for coronary angiography.

Methods

This cross-sectional study was carried out on 191 men patients with known coronary disease aged 40-70 years whom were admitted to angiography ward of Ahvaz teaching hospital, Ahvaz, Iran. Dietary patterns were investigated using 161-item semi-quantitative food frequency questionnaire. Anthropometric indices; blood pressure; serum levels of adiponectin and leptin, blood levels of glucose, total cholesterol, HDL-C, LDL-C, and triglycerides were measured. Patients were categorized based on the severity of coronary artery disease [number of vessel involved-single (VD1), double (VD2), triple (VD3)].

Results

Three major dietary patterns were recognized using a factor analysis approach: western, healthy, and traditional patterns. Linear regression analysis demonstrated that there was a negative association between healthy dietary pattern with LDL-C, total cholesterol, and triglycerides. This dietary pattern was positively related to HDL-C. Both traditional and western dietary patterns were related to fasting blood glucose level and lipid profile. General obesity was positively associated with traditional and western dietary patterns. There was a positive relationship between central obesity with traditional and western dietary patterns, but a negative association was reported between the healthy dietary pattern and central obesity. Traditional and western dietary patterns demonstrated a significant positive relationship with serum leptin levels and ratio of L/A, and an inverse relationship with adiponectin. Healthy dietary pattern had a significant negative association with serum leptin levels and ratio of L/A. Healthy dietary pattern was negatively related to the severity of vessel stenosis. Patients in the third quartile of healthy dietary pattern were less likely to have vessel stenosis (OR = 43%, 95% CI: 0.07-0.87).

Conclusions

The findings show that adherence to a healthy dietary pattern was negatively associated with coronary artery stenosis and its related risk factors. However, adherence to western and traditional dietary patterns was positively related to coronary artery disease risk factors.

Differences in dietary habits of people with vs without irritable bowel syndrome and their association with symptom and psychological status: A pilot study

BACKGROUND

Previous studies have demonstrated that dietary factors are involved in irritable bowel syndrome (IBS), but the role of diet was evaluated mostly based on food frequency questionnaire. Whether food categories, quantity per time, and intake frequency are different between IBS patients and non-IBS individuals has not been clearly clarified.

AIM

To explore differences in dietary habits of people with vs without IBS and their correlation with symptom and psychological status.

METHODS

A total of 220 questionnaires were administered in a community population and the Rome IV criteria was applied to diagnose IBS. The dietary questionnaire used in this study was multidimensional from food categories, quantity per time, and intake frequency, in contrast to "yes or no" classification used in previous studies. Questionnaires including IBS symptom severity scale (IBS-SSS), IBS quality of life, visceral sensitivity index, hospital anxiety and depression score (HADS), and gastrointestinal symptom rating scale were used to assess the participants. Rank sum test was used to compare the quantity per time and intake frequency between IBS patients and non-IBS participants. The correlation between psychological factors and diet was evaluated by Spearman correlation analysis. Logistic regression analysis was used to assess the possible dietary risk factors for IBS.

RESULTS

In total, 203 valid questionnaires were collected (response rate 92.3%). Twenty-five participants met the Rome IV criteria for IBS, including 15 (60.0%) women and 10 (40.0%) men. Compared with the non-IBS group, the quantity per time and intake frequency of soybean and its products, spicy food, and dry-fried nuts were statistically significant in IBS participants (P < 0.05). They were positively associated with IBS-SSS and HADS anxiety and depression scores (P < 0.05). Besides, seafood, soft drinks, vegetables, and fruits differed only in quantity per time. The intake frequencies of egg, barbecue, and coarse grain were statistically significant in IBS patients (P < 0.05). We also found that the frequency of soybean and its products (≥ 7 times/week, odds ratio = 11.613, 95% confidence interval: 2.145-62.855, P = 0.004) was an independent risk factor for IBS.

CONCLUSION

Both quantity per time and intake frequency, especially soybean, differ between IBS patients and non-IBS participants. Dietary habits might play potential roles in the pathophysiology of IBS.

The relationship between dietary intakes and prevalence of irritable bowel syndrome in adolescent girls: A cross-sectional study

BACKGROUND

Irritable bowel syndrome (IBS) is the most prevalent functional gastrointestinal disorder (FGID) leading to substantial reduction in quality of life. This study was undertaken to assess the relationship between diet and prevalence of IBS in female adolescents.

METHODS

In this cross-sectional study, data were examined on 988 adolescent girls from different areas of Mashhad and Sabzevar cities, Iran. A 168-item validated and reliable food frequency questionnaire (FFQ) for dietary intake was used in all the study participants. A diagnosis of IBS was made using the Rome III criteria.

RESULTS

Dietary macronutrients, energy, and selected micronutrients of IBS patients were similar to healthy subjects. Comparing the intake of caffeine between groups with and without IBS showed a higher level of consumption in the individuals with IBS (p-value = 0.02; p trend = 0.03). There was a significant positive association between caffeine intake and risk of IBS (odds ratio [OR] = 1.88, after adjustment for potential confounding variables). Although there was no significant difference in intakes of total dietary fiber (p-value = 0.23) and insoluble dietary fiber (p-value = 0.09) between IBS-positive and IBS-negative subjects, their soluble dietary fiber intake was significantly different (p-value = 0.02, a significant negative association was seen between soluble dietary fiber intake and IBS prevalence, after adjustment for potential confounding variables [p trend = 0.02; OR = 0.59]).

CONCLUSIONS

The higher intake of caffeine was positively associated with IBS prevalence. Additionally, a negative association was seen between soluble dietary fiber intake and the chance of having IBS.

Adherence to Dietary Approaches to Stop Hypertension Eating Plan and Prevalence of Irritable Bowel Syndrome in Adults

Background/Aims

Despite huge evidence on the link between adherence to dietary approaches to stop hypertension (DASH) eating pattern and several metabolic abnormalities, the association of this diet with irritable bowel syndrome (IBS) has not been investigated so far. We aim to examine the association between adherence to the DASH diet and prevalence of IBS symptoms and subtypes in adults.

Methods

This cross-sectional study was done among 3362 adult people in Isfahan, Iran. Usual dietary intakes were assessed using a validated 106-item dish-based semi-quantitative food frequency questionnaire. To investigate participants’ adherence to DASH-style diet, we created DASH score based on 8 main foods and nutrients emphasized or minimized in the DASH diet. Participants were classified into 3 categories according to their DASH-style diet scores. A validated modified Persian version of the Rome III questionnaire was applied for assessment of IBS.

Results

Totally, 22.2% of study participants were affected by IBS. After adjustment for potential confounding factors, we found that participants in the highest tertile of DASH score had lower odds of IBS (OR, 0.65; 95% CI, 0.50-0.83) compared with those in the lowest tertile. The same findings were also reached for IBS with constipation (OR for the highest vs the lowest tertile of DASH-style diet = 0.56; 95% CI, 0.38-0.85). No significant association was seen between adherence to DASH-style diet and IBS with diarrhea (OR, 1.31; 95% CI, 0.83-2.06).

Conclusions

We found a significant inverse association between adherence to DASH dietary pattern and odds of IBS and IBS with constipation. Further prospective studies are required to confirm these findings.

Development, validation and utilisation of dish-based dietary assessment tools: a scoping review

Objective:

To summarise the existing evidence of development, validation and current status of utilisation of dish-based dietary assessment tools.

Design:

Scoping review.

Setting:

Systematic search using PubMed and Web of Science.

Results:

We identified twelve tools from seventy-four eligible publications. They were developed for Koreans (n 4), Bangladeshis (n 2), Iranians (n 1), Indians/Malays/Chinese (n 1), Japanese (n 3) and Chinese Americans (n 1). Most tools (10/12) were composed of a dish-based FFQ. Although the development process of a dish list varied among the tools, six studies classified mixed dishes based on the similarity of their characteristics such as food ingredients and cooking methods. Tools were validated against self-reported dietary information (n 9) and concentration biomarkers (n 1). In the eight studies assessing the differences between the tool and a reference, the mean (or median) intake of energy significantly differed in five studies, and 26–83 % of nutrients significantly differed in eight studies. Correlation coefficients for energy ranged from 0·15 to 0·87 across the thirteen studies, and the median correlation coefficients for nutrients ranged from 0·12 to 0·77. Dish-based dietary assessment tools were used in fifty-nine studies mainly to assess diet–disease relationships in target populations.

Conclusions:

Dish-based dietary assessment tools have exclusively been developed and used for Asian-origin populations. Further validation studies, particularly biomarker-based studies, are needed to assess the applicability of tools.

Healthy lifestyle score and irritable bowel syndrome: A cross-sectional study in adults

BACKGROUND

Lifestyle modifications play an important role in the management of irritable bowel syndrome (IBS), but there is limited information on any associations of combined lifestyle-related factors with IBS in Middle Eastern populations. We, therefore, assessed the associations of a "lifestyle score," in analogy to lifestyle scores applied in studies of other disorders, with IBS in adults.

METHODS

In a cross-sectional study on 3363 Iranian adults, a healthy lifestyle score (HLS) was constructed using information about dietary habits, dietary intake, physical activity, smoking status, and psychological distress, which was collected using validated questionnaires. A modified version of the Rome III questionnaire (in Persian) was used to diagnose IBS and its subtypes.

KEY RESULTS

Individuals with the highest HLS had a 65% lower odds of having IBS compared with those in the lowest category (OR: 0.35; 95% CI: 0.26-0.48). Participants with healthy dietary habits, including regular meal pattern, slow/moderate eating rate, moderate intra-meal fluid consumption, moderate/long meal-to-sleep interval, and low/moderate consumption of fatty foods, had significantly lower odds of having IBS compared with those with unhealthy dietary habits (OR: 0.81; 95% CI: 0.69-0.96). Moreover, individuals with lower levels of psychological distress, compared with those with higher levels of distress, had significantly lower odds of IBS (OR: 0.49; 95% CI: 0.40-0.60).

CONCLUSIONS AND INFERENCES

Our data suggest that having an overall "healthy lifestyle" is related to substantially reduced odds of IBS, suggesting that adhering to a healthy lifestyle pattern, including dietary habits, diet quality, physical activity, smoking, and psychological distress, can be considered as a key management strategy for IBS.

Adherence to the pro-inflammatory diet in relation to prevalence of irritable bowel syndrome

Objective

There is no prior study that examined the association between nutrient-based dietary inflammatory index (DII) and odds of Irritable Bowel Syndrome (IBS). We examined the association between DII score and odds of IBS and its severity among Iranian adults.

Methods

In this cross-sectional study, dietary intakes of 3363 Iranian adults were examined using a validated Dish-based 106-item Semi-quantitative Food Frequency Questionnaire (DS-FFQ). DII was calculated based on dietary intakes derived from DS-FFQ. IBS was assessed using a modified Persian version of Rome III questionnaire.

Results

After adjustment for potential confounders, we found that participants in the highest quintile of DII score had greater chance for IBS compared with those in the lowest quintile (OR: 1.36; 95% CI: 1.03–1.80). By gender, we found a significant association between DII score and IBS among women (OR: 1.41; 95% CI: 1.00–2.00). By BMI status, overweight or obese (BMI ≥ 25 kg/m²) individuals in top quintile of DII score had greater odds for IBS than those in the bottom quintile (OR: 1.64; 95% CI: 1.07–2.53). No significant association was observed between a pro-inflammatory diet and severity of IBS symptoms.

Conclusions

Consumption of a pro-inflammatory diet was associated with increased odds of IBS, in particular among women and those with BMI ≥ 25 kg/m².

A Dietary Intervention with Reduction of Starch and Sucrose Leads to Reduced Gastrointestinal and Extra-Intestinal Symptoms in IBS Patients

Patients with irritable bowel syndrome (IBS) exhibit low-grade inflammation and increased gut permeability. Dietary sugar has been shown to contribute to low-grade inflammation and increased gut permeability, and to correlate with gastrointestinal (GI) symptoms. The aim of the present study was to examine the effect of a starch- and sucrose-reduced diet (SSRD) on gastrointestinal (GI) and extra-intestinal symptoms in IBS. One hundred and five IBS patients (82 women, 46.06 ± 13.11 years), with irritable bowel syndrome-symptom severity scale (IBS-SSS) > 175, were randomized to SSRD for 4 weeks or continued ordinary eating habits. The visual analog scale for irritable bowel syndrome (VAS-IBS), IBS-SSS, and 4-day food diaries were collected at baseline and after 2 and 4 weeks. After the intervention, one-third of the patients did not fulfill the criteria for IBS/functional gastrointestinal disorder. Half of the participants changed from moderate/severe disease to no/mild disease according to IBS-SSS. Comparisons between the groups showed decreased weight and sweet cravings, and parallel decreases in total IBS-SSS and extra-intestinal IBS-SSS scores, in the intervention group compared to controls (p < 0.001 for all). When calculating separate extra-intestinal symptoms, belching (p = 0.001), muscle/joint pain (p = 0.029), urinary urgency (p = 0.017), and tiredness (p = 0.011) were decreased after introduction of SSRD compared to controls. In conclusion, SSRD improves both GI and extra-intestinal symptoms in IBS.

Irregular Dietary Habits with a High Intake of Cereals and Sweets Are Associated with More Severe Gastrointestinal Symptoms in IBS Patients

Dietary advice constitutes one of the first choices of treatment for irritable bowel syndrome (IBS). We have recognized an increased prevalence of sucrase-isomaltase (SI) gene variants in IBS patients, possibly rendering starch- and sucrose-intolerance. The aims were to examine participants' dietary habits at baseline, to correlate habits with gastrointestinal (GI) symptoms and blood levels of minerals and vitamins, and to examine the effect of a starch- and sucrose-reduced diet (SSRD) on GI symptoms. In the study 105 IBS patients (82 women, 46.06 ± 13.11 years), irritable bowel syndrome-symptom severity scale (IBS-SSS)>175, were randomized to SSRD for 2 weeks or continued ordinary eating habits. Blood samples, visual analog scale for irritable bowel syndrome (VAS-IBS), IBS-SSS, and 4-day food diaries were collected at baseline and after 2 weeks. Patients with irregular dietary habits exhibited higher IBS-SSS than patients with regular habits (p = 0.029). Women already on a diet had lower ferritin levels than others (p = 0.029). The intervention led to 66.3% of patients being responders, with differences in the change of IBS-SSS (p < 0.001), abdominal pain (p = 0.001), diarrhea (p = 0.002), bloating and flatulence (p = 0.005), psychological well-being (p = 0.048), and intestinal symptoms' influence on daily life (p < 0.001), compared to controls. Decreased intake of cereals and sweets/soft drinks correlated with decreased scores.

Comparison of the metabolomic profiles of irritable bowel syndrome patients with ulcerative colitis patients and healthy controls: new insights into pathophysiology and potential biomarkers

BACKGROUND

Evaluation of the metabolomic profile of patients with irritable bowel syndrome offers an opportunity to identify novel pathophysiological targets and biomarkers that could discriminate this disorder from related conditions.

AIM

To identify potential urinary biomarkers that discriminate irritable bowel syndrome patients from ulcerative colitis patients in remission and healthy controls and to explore the pathophysiology of irritable bowel syndrome using a metabolomic approach.

METHODS

Urine samples were collected from 39 irritable bowel syndrome patients, 53 ulcerative colitis patients in clinical remission and 21 healthy controls. Urinary metabolites were identified and quantified using direct infusion/liquid chromatography tandem mass spectrometry and gas-chromatography mass spectrometry.

RESULTS

Patients with irritable bowel syndrome had a unique urinary metabolome that could separate them from ulcerative colitis patients with an area under the curve = 0.99 (95% confidence interval 0.95-1.00). The most important metabolites for this separation were a group of amino acids and organic acids. In addition, subjects with irritable bowel syndrome could be discriminated from healthy controls using their metabolic fingerprints. Irritable bowel syndrome patients had lower urinary Phosphatidyl choline acyl-alkyl C38:6, dopamine and p-hydroxybenzoic acid than healthy controls. Levels of some urinary metabolites including histamine correlated significantly with irritable bowel syndrome symptom severity scores.

CONCLUSIONS

Irritable bowel syndrome patients have a unique urinary metabolomic profile compared to ulcerative colitis patients in clinical remission or healthy subjects. These data suggest that metabolomic profiling may provide important insights into pathophysiology and testable biomarkers to discriminate irritable bowel syndrome from other disorders that can mimic this condition and can be used to assess its severity and identify potential novel pathophysiological pathways.

The Relationship between Dietary Patterns with Blood Pressure in Iranian Army Staffs

Background:

Hypertension is one of the most common noncommunicable diseases in the world. One of the most effective factors on blood pressure (BP) is nutrition. The aim of this study was to examine the relationship between dietary patterns and BP among military staffs.

Materials and Methods:

The study was carried out among 405 military staffs between 22 and 51 years old. Demographic, anthropometric information, and BP of participants were evaluated by standard methods. The dietary intakes were collected using a food frequency questionnaire (FFQ). Dietary patterns were identified using a posteriori method, factor analysis, and based on the FFQ. To check the relationship between BP and dietary patterns, we used multivariate linear regression in different models, relationship were adjusted for Age, sex, marital, smoking, income, body mass index, waist-to-hip ratio, family history of hypertension, energy intake, and physical activity level.

Results:

Two dominant dietary patterns were identified in the participants: Healthy and western pattern. The association of dietary patterns with systolic BP (SBP) and diastolic BP (DBP) was exhibited in different models. There was no relationship between SBP and DBP with healthy pattern (P = 0.269 and P = 0.638, respectively) and western pattern (P = 0.648 and P = 0.315, respectively) after adjustments.

Conclusion:

Our findings indicated that dietary patterns did not have any significant relationship with SBP and DBP after adjustment for confounders in the healthy military. To identify the dietary patterns associated with BP in healthy military, more strong design studies and more participants should be conducted in the future.

Association Between Ultra-Processed Food Consumption and Functional Gastrointestinal Disorders: Results From the French NutriNet-Santé Cohort

OBJECTIVES

Ultra-processed foods (UPF) consumption has increased over the last decades and is raising concerns about potential adverse health effects. Our objective was to assess the association between UPF consumption and four functional gastrointestinal disorders (FGIDs): irritable bowel syndrome (IBS), functional constipation (FC), functional diarrhea (FDh), and functional dyspepsia (FDy), in a large sample of French adults.

METHODS

We analyzed dietary data of 33,343 participants from the web-based NutriNet-Santé cohort, who completed at least three 24 h food records, prior to a Rome III self-administered questionnaire. Proportion (in weight) of UPF in the diet (UPFp) was computed for each subject. The association between UPFp quartiles and FGIDs was estimated by multivariable logistic regression.

RESULTS

Participants included in the analysis were mainly women (76.4%), and the mean age was 50.4 (SD = 14.0) years. UPF accounted for 16.0% of food consumed in weight, corresponding to 33.0% of total energy intake. UPF consumption was associated with younger age, living alone, lower incomes, higher BMI, and lower physical activity level (all p < 0.0001). A total of 3516 participants reported IBS (10.5%), 1785 FC (5.4%), 1303 FDy (3.9%), and 396 FDh (1.1%). After adjusting for confounding factors, an increase in UPFp was associated with a higher risk of IBS (_aOR _{Q4 vs. Q1} [95% CI]: 1.25 [1.12-1.39], p-trend < 0.0001).

CONCLUSIONS

This study suggests an association between UPF and IBS. Further longitudinal studies are needed to confirm those results and understand the relative impact of the nutritional composition and specific characteristics of UPF in this relationship.

A Western dietary pattern is associated with elevated level of high sensitive C-reactive protein among adolescent girls

BACKGROUND

Serum high sensitive C-reactive protein (hs-CRP), is an indicator of low-grade inflammation, and is associated with several non-communicable diseases. The effects of diet on inflammation have not been extensively investigated, particularly among adolescents. We aimed to examine the association between major dietary patterns and elevated serum level of hs-CRP among Iranian adolescent girls.

MATERIALS AND METHODS

In this cross-sectional study, a total of 670 adolescent girls were recruited from several schools in different areas of Mashhad and Sabzevar cities, Iran. The dietary intakes of study participants were collected using a 147-item food frequency questionnaire. To identify major dietary patterns based on the 40 food groups, we used principal component analysis. Serum concentration of hs-CRP was measured using commercial kits and the BT-3000 auto-analyser. To investigate the association between dietary patterns and elevated serum level of hs-CRP, we used logistic regression analysis.

RESULTS

Three specific dietary patterns were identified: (i) healthy, (ii) traditional and (iii) western dietary patterns. A significant association was found between more adherence to Western dietary pattern and elevated serum level of hs-CRP (OR: 1.58; 95% CI: 1.02-2.42, P-trend = .03); these association remained significant after adjustment for potential confounders. However, there was no significant relationship between healthy and traditional dietary patterns and elevated serum level of hs-CRP.

CONCLUSION

Our results indicate that there is a significant positive association between more adherence to Western dietary pattern and higher serum levels of hs-CRP among Iranian adolescent girls. Further studies, particularly longitudinal intervention studies may be required to clarify these relationships.

Dietary behaviors in relation to prevalence of irritable bowel syndrome in adolescent girls

BACKGROUNDS AND AIMS

There is limited evidence regarding the relationship between dietary behaviors and irritable bowel syndrome (IBS). This study aimed to explore the association between diet-related practices and prevalence of IBS.

METHODS

The study was conducted among 988 adolescent girls living in Iran. Dietary behaviors were pre-defined and assessed in nine domains using a pre-tested questionnaire. To investigate the association between diet-related practices and the presence of IBS, this study used logistic regression analysis in crude and adjusted models.

RESULTS

The prevalence of IBS was 16.9% in this population. Compared with individuals who did not consume fluid with their meal, those who always consumed fluid with meals had a greater chance of IBS (odds ratio [OR]: 2.91; P: 0.01). This study found a direct relationship between a greater intake of spicy food and IBS prevalence (OR: 5.28; P: 0.02). The individuals who ate fried foods every day also had a greater risk of IBS compared with those who did not consume fried foods (OR: 1.65; P: 0.01). The subjects who had lost ≥ 5 teeth had 2.23 times greater odds for IBS than the individual who had lost ≤ 1 tooth (OR: 2.23; P: 0.01) was a significant inverse relationship between the chewing sufficiency and the risk of IBS (OR: 4.04; P: 0.02). These associations remained significant after controlling for potential confounder.

CONCLUSIONS

Intra-meal fluid intake, chewing insufficiency, higher tooth loss, and the consumption of spicy and fried food were associated with increased risk of IBS. Prospective studies are needed to confirm these findings.

Food Patterns and Framingham Risk Score in Iranian Adults: Tehran Lipid and Glucose Study: 2005-2011

BACKGROUND

Healthy dietary habits can prevent cardiovascular diseases (CVD). The aim of this study was to investigate the association between dietary patterns and predicted risk of CVD development using Framingham Risk Score (FRS) in Iranian population over 6 years of follow-up.

METHODS

In this prospective study, 2333 individuals aged 30-74 years with a 10-year predicted risk <10% and without a CVD diagnosis at baseline were recruited from participants in the third survey of Tehran Lipid and Glucose Study. Usual dietary intake was assessed using a validated semiquantitative food frequency questionnaire. Dietary patterns were identified using factor analysis. The risk of developing CVD was evaluated using FRS questionnaire. The association between dietary patterns and risk of development of CVD was evaluated using binary logistic regression models.

RESULTS

Three major dietary patterns were identified, which explained 32% of total variance in dietary intake of participants. The healthy dietary pattern was characterized by high intake of fruits, fruit juices, vegetables, liquid oils, and nuts and lower intake of refined grains. The western dietary pattern was characterized by high intake of fast foods, soft drinks, sweets and sugars, and red meat, organ meat, and egg. The traditional dietary pattern was characterized by high intake of legumes and vegetables and low intake of high-fat dairy products. After adjustment for all confounding factors, participants in the highest tertile of the healthy dietary pattern had a lower risk of CVD development (odds ratio [OR]: 0.67; 95% CI: 0.51-0.87, P-trend: 0.003).

CONCLUSION

Our findings in a large cohort of Iranian population confirm the current recommendation regarding consuming healthy dietary pattern for primary prevention of CVDs.

Western Dietary Pattern Is Associated with Irritable Bowel Syndrome in the French NutriNet Cohort

Background: Diet appears to play a key role in the pathogenesis of the irritable bowel syndrome (IBS). Some dietary patterns (DP) could increase the risk of triggering or worsening IBS symptoms. This cross-sectional study aimed to assess the association between a posteriori derived DP and IBS in a large French population, the web-based NutriNet-Santé cohort. Methods: Study population included participants of the NutriNet-Santé study who completed a questionnaire based on Rome III criteria assessing IBS. A principal component analysis (PCA) was performed to identify major DPs based on 29 food groups' consumption. Associations between DP quintiles and IBS were investigated with multivariable logistic regressions. Results: 44,350 participants were included, with 2423 (5.5%) presenting IBS. Three major DP were extracted using PCA, "healthy," "western," and "traditional." After adjustments on confounders, the "western" DP was positively associated with IBS (OR _{Q5 vs. Q1} = 1.38, 95% CI 1.19-1.61, p trend < 0.0001) and the "traditional" DP was positively associated with IBS in women (OR _{Q5 vs. Q1} = 1.29 95% CI 1.08-1.54, p trend = 0.001). Conclusions: In this study, a "western" DP-highly correlated with the consumption of fatty and sugary products and snacks-was associated with a moderate increased risk of IBS.

Smoking in Irritable Bowel Syndrome: A Systematic Review

OBJECTIVE

The aim of this review was to examine (1) the prevalence of smoking in subjects with irritable bowel syndrome (IBS), (2) whether smoking prevalence significantly differs between subjects with and without IBS, and (3) whether smoking significantly predicts the presence or the development of IBS.

METHODS

Articles were retrieved by systematically searching the Scopus, Web of Science, and PubMed electronic databases from inception to July 2016, using the keywords "smoking" and "tobacco" combined with "irritable bowel syndrome." Reference lists of included articles were also searched. Articles were included if they (1) reported data on smoking prevalence in subjects with IBS and/or on the association (assessed by means of multivariate analyses) between smoking and IBS, (2) identified IBS according to Manning criteria or Rome I-III criteria, (3) were English-language articles, and (4) involved only adult subjects.

RESULTS

The electronic searches yielded a total of 1,637 records, and 42 articles met inclusion criteria. Another 13 articles were retrieved through manual search, leading to a total of 55 included articles. Smoking prevalence in subjects with IBS was assessed by 48 articles and ranged from 0% in university students to 47.1% in patients with microscopic colitis. Thirty-three articles compared smoking prevalence between subjects with and without IBS. In 25 articles no significant difference was found. In seven articles smoking was significantly more frequent in subjects with IBS compared to those without IBS, while one study found a significantly higher smoking prevalence in controls. Eighteen multivariate analyses assessing the association between smoking and IBS were presented in 16 articles. Only one study employed a prospective design. In 11 analyses, smoking was not significantly associated with IBS after adjusting for covariates. In seven studies smoking independently predicted the presence of IBS.

CONCLUSIONS

According to the selected articles, a significant association between smoking and IBS cannot be confirmed. However, different shortcomings may hinder generalizability and comparability of many studies. A dimensional assessment of smoking, a prospective design, the differentiation between IBS subgroups, and the recruitment of patients in clinical settings, especially in primary care, are necessary to clarify the role of smoking in IBS.

Irritable bowel syndrome is concentrated in people with higher educations in Iran: an inequality analysis

OBJECTIVES

Like any other health-related disorder, irritable bowel syndrome (IBS) has a differential distribution with respect to socioeconomic factors. This study aimed to estimate and decompose educational inequalities in the prevalence of IBS.

METHODS

Sampling was performed using a multi-stage random cluster sampling approach. The data of 1,850 residents of Kish Island aged 15 years or older were included, and the determinants of IBS were identified using a generalized estimating equation regression model. The concentration index of educational inequality in cases of IBS was estimated and decomposed as the specific inequality index.

RESULTS

The prevalence of IBS in this study was 21.57% (95% confidence interval [CI], 19.69 to 23.44%). The concentration index of IBS was 0.20 (95% CI, 0.14 to 0.26). A multivariable regression model revealed that age, sex, level of education, marital status, anxiety, and poor general health were significant determinants of IBS. In the decomposition analysis, level of education (89.91%), age (−11.99%), and marital status (9.11%) were the three main contributors to IBS inequality. Anxiety and poor general health were the next two contributors to IBS inequality, and were responsible for more than 12% of the total observed inequality.

CONCLUSIONS

The main contributors of IBS inequality were education level, age, and marital status. Given the high percentage of anxious individuals among highly educated, young, single, and divorced people, we can conclude that all contributors to IBS inequality may be partially influenced by psychological factors. Therefore, programs that promote the development of mental health to alleviate the abovementioned inequality in this population are highly warranted.