Journal of Gastroenterology & Hepatology Research Category: Medical Type: Review Article

Unravelling the Digestive Dilemma: Investigating Dietary Influence on Irritable Bowel Syndrome through Narrative Review

Shraddha Saroj1*, Kalpna Gupta2, Sumit Rungtav3, Narendra Kumar4 and Devanand Bharti5
1 Research Scholar (Senior Research Fellow), Food Science and Nutrition, Department of Home Science, Banaras Hindu University, Varanasi, India
2 Professor, Human Development, Department of Home Science, Banaras Hindu University, Varanasi, Uttar Pradesh, India
3 Associate Professor, Department of Gastroenterology (Head), King George Medical University, Lucknow, Uttar Pradesh, India
4 Associate Professor, Department of Trauma Surgery, King George Medical University, Lucknow, Uttar Pradesh, India
5 Senior Resident, Department of Ophthalmology, King George Medical University , Lucknow, Uttar Pradesh, India

*Corresponding Author(s):
Shraddha Saroj
Research Scholar (Senior Research Fellow), Food Science And Nutrition, Department Of Home Science, Banaras Hindu University, Varanasi, India
Tel:+91 9653058900,
Email:shradz26@bhu.ac.in

Received Date: Jun 09, 2025
Accepted Date: Jun 19, 2025
Published Date: Jun 26, 2025

Abstract

Background and Objective

Functional gastrointestinal disorders (FGIDs) are among the most common and chronically persistent disorders affecting the digestive system. IBS is an apt example of chronic FGID that is associated with abdominal pain and discomfort which may be present along with other gastrointestinal symptoms such as bloating, fullness, belching, constipation, diarrhoea etc. Although the etiology of IBS may not be understood clearly, it mainly depends on the pathophysiology of the host and its interaction with the environment. Among the environmental factors, the role of the diet must be studied exclusively as most of the IBS patients have reported that their symptoms become worse after the consumption of certain foods. Thus, there was need to carry out Narrative Review to study the role of food items, probiotics and fiber consumption and impact of available dietary guidelines on the health of IBS patients. 

Methods

A systematic literature search was conducted following PRISMA guidelines at three databases that is PubMed, Embase and Google Scholar. Articles that were published in past 10 years were included. Mainly observational studies, randomized controlled trials, systematic reviews and meta-analysis that were available in English language were included in this review. The automation tool was helpful in screening the articles. After reading the title and abstract, selected articles were further screened in detail to be included or excluded. 

Key content and Findings

The main goal of IBS treatment is to provide relief from symptoms rather than cure. The factors that exacerbate IBS symptoms need to be identified and conditions that are favourable to control these factors should be implemented. The diet may directly affect the gut microflora and therefore by modifying the dietary factors, improvement can be observed among IBS patients. Low FODMAP diet is highly recommended for IBS patients but in developing countries, these guidelines may not be economically feasible and may also cause nutritional deficiency in long run. Also, there is a huge difference in the diet followed in the Asian countries and the Western world, thereby responsible for the vast variation that can be seen in the prevalence rates, gender differences and manifestation of symptoms Hence, there is a need to formulate individualized diet for the patients based on their dietary history, socio-economic status, willingness to change, environmental factors, socio-cultural believes and associated psychological comorbidities. This can only be achieved by a team of well-trained dieticians working in collaboration with doctors, nurses and other health care professionals from clinical nutrition, gastroenterology, psychiatry and associated departments. 

Conclusions

The Narrative Review concludes that there is need to adopt individualized approach for treating IBS patients. Although the benefits of low FODMAP diet are known, universalization may not be the best approach. Proper hydration and regular sleep are beneficial for all the IBS patients around the world. A team of specialists from the department of gastroenterology and dietetics should take the initiative of formulating individualized diet which will decrease the number of patient’s visits thereby reducing the economic burden on the individual and health care system in long run.

Keywords

Diet; Fiber; Irritable Bowel Syndrome; Probiotics

Introduction/Background

Functional gastrointestinal disorders (FGIDs) are among the most common and chronically persistent disorders affecting the digestive system [1]. Functional constipation, dyspepsia and Irritable Bowel Syndrome (IBS) are the most reoccurring gastrointestinal disorders affecting the quality of life [1,2] IBS is an apt example of chronic FGID that is associated with abdominal pain and discomfort which may be present along with other gastrointestinal symptoms such as bloating, fullness, belching, constipation, diarrhoea etc. [3].The prevalence of IBS is 10-20% in developed countries [4] but the availability of data about developing countries is sparce. IBS patients are more likely to be on medical leave which affects their work productivity and also causes economic burden [5]. This affects their quality of life, along with degradation in family and social life [6]. Thus, IBS is a multisymptomatic condition that affects patients physically, mentally, socially and economically [7].

IBS is a disorder of gut-brain interaction in which psychological factors play a significant role [8]. 30% - 50% of FGID patients suffer from psychological comorbidities such as anxiety and depression [9]. A systematic review and meta-analysis have reported that patients suffering from IBS have significantly high levels of anxiety and depression than healthy controls [10] (Figure 1).

commonly reported clinical manifestationsFigure 1: Shows commonly reported clinical manifestations and psychiatric associations in irritable bowel syndrome patients.

Note: The fig. is drawn using Canva, the graphic design tool.

Diagnosis

IBS can be diagnosed by following the latest ROME IV criteria according to which: IBS is a functional bowel disorder with recurrent abdominal pain that is associated with defecation or a change in bowel habits. Disordered bowel habits are typically present (i.e., constipation, diarrhea or a mix of constipation and diarrhea), as are symptoms of abdominal bloating/distension. Symptom onset should occur at least 6 months prior to diagnosis and symptoms should be present during the last 3 months. Recurrent abdominal pain atleast 1 day/week in the last 3 months associated with two or more of the following: a) Related to defecation, b) Associated with a change in frequency of stool, c) Associated with a change in the form (appearance) of stool [11].

Rome IV criteria have replaced the formerly used Rome III criteria, according to which the term ‘discomfort’ is replaced by ‘pain’. Also, the frequency of pain from 3 times in month (Rome III) have been specified to at least one day per week (Rome IV). The updated criteria has resulted in a decrease in the prevalence of IBS patients [12].

Classification

According to stool pattern, IBS is classified as: a) IBS with constipation (IBS-C):

IBS is further classified as 1) sporadic or non-specific and 2) post-infection. In the sporadic type, the IBS symptoms occur without any history of gastrointestinal infection whereas in post-infection cases, IBS may be observed in patients with a history of infection mainly affecting the digestive system. Post-infection IBS covers 6% to 17% of IBS patients [13]. IBS patients visit the physician more often than the patients of hypertension and diabetes mellitus. 12 to 14% of primary care visits and 28% of referral to the gastroenterology department are due to IBS [13].

Significance of the study

Although the etiology of IBS may not be understood clearly, it mainly depends on the pathophysiology of the host and its interaction with the environment. Among the environmental factors, the role of the diet must be studied exclusively as most of the IBS patients have reported that their symptoms become worse after the consumption of certain foods [14]. Food choices along with psychosocial factors play a significant role in symptom emanation and perpetuation [3,13,15].

The main aim of this Narrative Review is to understand the role of different food choices on the health of IBS patients around the world. Only the latest studies done in the past 10 years are included in this review so that they can be useful in providing the current developments in this field and also present prospects of research in the coming future.

Methodology

A systematic literature search was conducted following PRISMA guidelines at three databases that is PubMed, Embase and Google Scholar to acquire comprehensive and meaningful insights. The following keywords were used, “Diet” OR “Role of diet” AND “irritable bowel syndrome” OR “IBS” AND “fiber” AND “Probiotics” AND “functional gastrointestinal disorder” OR “FGID”. The publication date was customized to past ten years so that the latest developments in the field can be reviewed, then the articles were screened for their eligibility regarding titles and article type. If the title and abstract were not enough for making a decision then full articles were studied in detail to make a decision regarding its inclusion or exclusion.

The quality of papers that were included was checked thoroughly which involved the selection criteria of participants, diagnosis, study designs that were used, methodology followed and presentation of results. Since the preparation of this Narrative Review did not involve any human trial, ethical clearance was not taken. 

Inclusion and Exclusion Criteria 

The articles that were published in English language, were selected for the study. Studies which included IBS patients ≥18 years were included, any study about paediatric patients (below 18 years) was excluded. Studies in which diagnosis was done by Rome IV, III, II, I or Manning criteria were included. Randomized clinical trials, systematic reviews, observational study, case-control study and meta-analysis were included. Non-human trials were excluded from the study. Articles in any other language except English or other gastrointestinal disorder except IBS or organic diseases were excluded.

Data extraction 

The following data was extracted from each included study:

Author’s name, year in which the study was conducted, country/region, sample size, age of participants, study design, type of intervention provided and the main outcome of the study.

Results And Discussion

Role of diet:

Food is both the trigger as well as treatment for IBS. The dietary habits of people differ in different countries and even places within the countries. Diet is an important factor which can alter the gut microbiota [16,17,14]. In a survey consisting of 1,242 IBS patients, the majority of them had an opinion that modifying diet can improve the severity of symptoms in them [18]. Recent research by the division of gastroenterology in Boston, USA suggested that different subtypes of IBS differ in dietary habits and gut microbial composition and function, indicating potential research in the field of gut-microbiome interactions [19]. One common advice given to all the IBS patients around the world is to avoid certain foods that can worsen IBS symptoms. The IBS patients are advised to eat regular meals in a calm manner and chew it properly [16]. 

Low FODMAP diet

Recently many studies have indicated the benefits of low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) diet for IBS patients [3,16]. The short chain carbohydrates are not easily digested and absorbed by the IBS patients. They can cause osmotic flow towards large bowel. These partially digested carbohydrates are easily fermented by the intestinal microbes thus, producing symptoms such as bloating, distension, flatulence etc. To alleviate IBS symptoms low FODMAP diet is advised [20]. A study conducted on 20 IBS-D patients showed that using low FODMAP diet for 90 days was beneficial in reducing IBS symptoms as well as improved their anthropometric profile [17]. Several systematic reviews and meta-analysis have indicated that low FODMAP diet is beneficial in 50% of the IBS patients [6] leaving with a challenge to formulate diet for the remaining patients. 

A low FODMAP diet consists of food groups that includes fruits, vegetables, cereals, tubers, dairy products, legumes, sweeteners etc. In Asian countries including India and Korea, onions and garlic are consumed regularly which are high FODMAP foods. In western countries processed meat, dairy products and wheat products such as bread form a major part of their diet which are also high FODMAP foods [20]. The currently available low FODMAP diet is formulated based on studies vastly carried out in western countries. Still detailed data about the dietary practices followed in the developing world including Asian countries such as Korea and India with reference to IBS is sparse. Moreover, high FODMAP wheat products such as chapatti (staple food of North India), dalia, laddu, biscuits are consumed regularly by Indian population. Along with this there is an increase in the consumption of refined wheat flour products such as bread, noodles and other convenient foods by the Asian population including Korea and India. Thus the implementation of a low FODMAP diet come with its own challenges such as availability, vegetarianism, social acceptability, nutritional deficiency in long run and it might be not be an affordable option for chronic disease like IBS [6].    

Traditional diet

Both traditional as well as low FODMAP diet is benefial for IBS patients. However, low FODMAP diet has also shown significant improvement in gut microbiota [16]. Some common food items that were reported by IBS patients that may exacerbate their symptoms include coffee, alcohol, spicy and fatty foods but more research need to be done in order to find significant association. 

A recent systematic review and meta-analysis reported that coffee drinkers have a reduced likelihood of developing IBS as compared to the non-drinkers. Although they also pointed out that the included studies had major methodological issues and there is a need for more investigations to clearly understand the biological mechanism [21].  

Gluten free and lactose free diet

Coeliac disease and lactose intolerance are other common gastrointestinal disorders affecting the population around the globe. Each of these can be present simultaneously with IBS. Some studies have reported that gluten free diet and lactose free diet are beneficial to IBS patients however the evidence are conflicting. More research is required to obtain data regarding which part of wheat or milk may act as a trigger for IBS symptoms. 

Current Dietary guidelines

Dietary guidelines given by National Institute for Health and Care Excellence (NICE) and British Dietetic Association includes reduction in fats, caffeine, excessive fiber intake and avoidance of bloating or flatulence causing vegetables like onion, cabbage and beans and carbonated beverages. 

The modified NICE (mNICE) diet is another option for IBS patients in which they have to avoid excess alcohol and caffeine, eat small frequent meals and avoid large meals and also avoid specific food triggers which vary from patient to patient. In long term mNICE diet is easy to follow and it won’t cause any issue of malnutrition whereas low FODMAP diet is difficult to follow in long term, may cause deficiencies [22] and are also expensive for patients living in developing countries (Table 1).

Study

Region

Diagnosis

n

(Sample)

Study Design

Interventional

Groups

Duration

Result

[23]

Australia

Rome IV criteria

n=59

IBS patients

(18-65 years)

RCT

n=29, Mediterranean diet (MD) &

n=30, control

6 weeks

**IBS-SSS score was low in MD group as compared to control (p<0.001).

Reduction in IBS-SSS was correlated with ***MEDAS score (p<0.001).

[24]

Italy

Rome III-IV criteria

n=42

IBS-D patients

(Not mentioned)

Single blind, parallel group RCT

n=21, Low Fodmap Diet & n=21, Tritordium based diets

Jan/2018-Sept/2020, Intervention for 12 weeks

According to IBS-SSS the two diets equally improved the gastrointestinal symptoms and ****QoL.

[25]

Sweden

Rome IV criteria

n=103

IBS patients

(18-70 years)

Double blind, placebo controlled, 3-way crossover RCT

1 week intervention with FODMAP (50g/day), Gluten (17.3g/day) or placebo followed by 1 week washout period

Sept/2018-June/2019

FODMAP group indicated modest improvement in **IBS-SSS whereas placebo and gluten groups showed no difference.

[26]

Sweden

Rome-III

criteria

IBS patients

(18-65 years)

Novel approach:

4-day food diary intregrated into food tree and relation with gut microbiota

n=149,

IBS

n=52,

healthy controls

Not mentioned

Study showed that individuals with severe IBS symptoms had higher intake of poor-quality foods at main meals as compared to patients with mild IBS symptoms and controls.

[27]

China

Rome-III

criteria

n=108,

IBS-D patients

(31-57 years)

RCT

n=54,

Low FODMAP

n=54,

*TDA

Oct/2017-May/2018

Patients taking low FODMAP diet achieved earlier symptom improvement than TDA. Although both the diets reduced IBS-D symptoms.

[16]

Sweden

Rome III criteria

n = 67

IBS patients

(21-63 years)

RCT

n = 34,

traditional

diet

n = 33,

Low FODMAP

4 weeks

Low FODMAP diet was associated with reduced Bifidobacterium and Actinobacteria whereas traditional diet was not significantly associated with change in faecal bacterial profile

[28]

Germany

Rome III

criteria

n = 59

IBS patients

(18-75 years)

RCT

n = 30,

yoga

n = 29,

low FODMAP

12-24 weeks

Significant difference was not observed between the intervention groups with reference IBS-SSS score.

[29]

Netherlands

Rome III criteria

n=194, IBS patients

n=186, healthy controls

(18-75 years)

Case-Control study

-

May/2012–April/2015

Quality of diet in IBS patients was lower as compared to controls as they consumed high amounts of fats, sugars and processed meat with lower amounts of fiber.

[30]

London, U.K.

Rome-III

criteria

n = 104,

IBS-patients

(18-65 years)

RCT

 

n = 27, Sham diet + placebo

n = 26, sham diet + probiotic,

n = 24, low FODMAP + placebo

n = 27, low FODMAP + probiotic

4 weeks

Total mean IBS-Severity Scoring System score was significantly lower for patients on the low FODMAP diet as compared to sham diet (p = 0.001).

Table 1: Research showing role of diet in irritable bowel syndrome, chronologically arranged studies of past ten years.

TDA: Traditional dietary advice, IBS-SSS: IBS symptom severity score, MEDAS: Mediterranean Diet Adherence Screener, Quality of Life

Role of Fiber

There are mainly two kinds of fibers found in foods, water-soluble dietary fiber and water-insoluble dietary fiber [1]. These fibers play a very significant role in maintaining gut health. Both the fibers play different roles in the digestive system, the coarse or insoluble fiber such as bran improves gut motility by stimulating the secretion of mucous and water [1]. It also increases bulk or volume of food and keeps full for longer duration. On the other hand the soluble fibers have high water holding capacity as they form gels, thus keeping the stools moist and soft, which is essential for easy passage or excretion (eg: psyllium husk) [1]. Recent studies have indicated cautious use of fiber in IBS patients as they may exacerbate IBS symptoms [31].

In a randomized controlled trial (RCT) consisting of 3 groups of IBS patients, in which the first group was given soluble fiber (ispaghula, psyllium), the second group was given bran and the third group was given placebo (rice flour) [32]. The result indicated that there was no significant difference between bran and placebo control group, but soluble fiber significantly reduced the abdominal pain and distension in IBS patients [32]. Low fiber diet may increase the number of IBS-C patients [33]. A systematic review and meta-analysis consisting of 14 RCT’s involving 906 patients reported the significant benefits of soluble fiber whereas no useful or harmful effect of bran was indicated [31].   

In a crossover RCT, IBS – C patients in one group were given inulin, choline and silymarin (Stoptoxin) along with diet for 28 days and the other group was only advised diet. There was significant decrease (p=0.004) in abdominal pain as well as abdominal bloating (p=0.04) when IBS-C patients were advised diet with Stoptoxin. Thus, these studies have concluded that fiber supplementation may be effective in improving global IBS symptoms [34]. Another research published in 2023, studied the effect of guar gum (a low viscosity soluble fiber) on IBS patients. They reported that IBS patients with normal baseline microbiota showed positive response to guar gum and those with low microbiota diversity did not show significant improvement, concluding that baseline microbiota play a significant role in influencing the response towards fiber intervention [35]. 

Dietary fiber guidelines

The recommended dietary allowance (RDA) of fiber for Indians is 40g/2000 kcal consumed. It is considered as a safe limit [36]. NICE (National Institute for Care and Excellence) recommends fiber modification i.e., not a mere increase or decrease in the amount of fiber rather adding variety of fiber as IBS patients may be intolerant to certain specific fibers such as wheat bran. The adequate intake (AI) of fiber recommended by Australian dietary guidelines suggests 30g of fiber for adult males and 25g for adult females whereas to reduce chronic gastrointestinal diseases the suggested dietary target (SDT) is 38g/day for adult males and 28g/day for adult females [37].  The modified NICE guidelines also recommend the use of psyllium husk as a source of fiber for IBS patients along with proper hydration [22] (Table 2). 

Study

Region

Diagnosis

n (Sample)

Study Design

Interventional

Groups

Duration

Result

[35]

Australia

Rome IV Criteria

n=40

IBS Patients (18-80 years)

Prospective Study

n=14, normal gut microbiota diversity & n=26, low gut microbiota diversity were given *PHGG (10g/day) in 300ml of water

Intervention: 1-30 &

31-90 days

Follow up:

91-120 days

The IBS patients with nomal gut microbiota showed positive response to *PHGG intervention and also reported decreased **IBS-SSS score whereas IBS patients with low gut microbiota diversity did not show significant reduction compared to baseline.

[38]

Romania

Rome IV Criteria

n = 51

IBS – C

Patients

(22-77 years)

Crossover

RCT

 

n = 24, diet

n = 23, diet + Stoptoxin (inulin, choline and silymarin)

n = 4, lost patients

4-8 weeks

Abdominal pain severity and abdominal bloating improved significantly in diet + Stoptoxin group.

[39]

 

London

Rome III criteria

n = 40

IBS-C

Patients

(18-70 years)

Pilot RCT

n = 14,

2 tablespoons of linseed

n = 13,

ground linseed

n = 13, control (no linseed)

4 weeks

No significant changes in stool frequency in any group

[32]

Netherlands

Rome II criteria

n = 275

IBS patients

(18-65 years)

RCT

 

n = 85 psyllium,

n = 97 bran,

n = 10 placebo

3 months

Psyllium group shows significant improvement in IBS patients

[40]

England

Rome criteria

(Not specified)

n = 28

IBS-C

Patients

(18-70 years)

RCT

n = 14

coarse wheat bran,

n = 14

low fiber placebo

8-12 weeks

Interventional group was interviewed and reported improvement

Table 2: Research showing role of fiber in irritable bowel syndrome, chronologically arranged studies of past ten years.

PHGG: Partially hydrolyzed guar gum (low viscosity soluble fiber),

IBS-SSS: IBS symptom severity score 

Role of Probiotics

The term “Probiotics” was first coined by WHO/FAO, they are live organisms which when consumed in adequate amounts are beneficial to the health of people [41]. In case of IBS patients when probiotics are given in proper amount and composition then they may be beneficial in producing the desired effects [22]. In order to obtain the benefits, the probiotics should be able to survive the effect of acid in stomach and bile and pancreatic juice in the small intestine [41].  Many studies have indicated that the microbiota of IBS patients is affected by several factors resulting in symptoms such a bloating, belching, flatulence and distention. Many IBS patients show a decrease in Lactobacillus and Bifidobacterium sp. which are usually important component of probiotics [4]. In a study, mucosal analysis demonstrated lower biodiversity of luminal microbiota in 16 IBS-D patients in comparison to 12 healthy controls [42].  Studies have indicated that in IBS patients, the diversity of intestinal microbiota is reduced as compared to healthy individuals [14,43]. Therefore, probiotics are given with an aim to manipulate the intestinal microbiota thereby improving IBS symptoms.

Several systematic reviews and meta-analysis have encouraged the use of probiotics for improvement of IBS symptoms as compared to placebo, however the limitations of the methodology followed to proceed towards such conclusions cannot be ignored [43]. 4th Triennial Yale/Harvard Workshop recommended the use of Bifidobacterium infantis, Bifidobacterium animalis and Lactobacillus plantarum 299V for IBS patients [44]. 

In a recent RCT, the IBS-C and IBS-D patients were supplemented with probiotic for 8 weeks and wash out period of 2 weeks which was compared with placebo given to 17 IBS patients from both groups. There was no significant effect of administering probiotic on the symptoms of IBS patients which was estimated by Francis Severity Score (FSS: validated questionnaire for IBS patients). Also, the gastrointestinal microbiota which was analysed by qPCR did not manifest any significant changes, as the number of target microbes may be below the detection limit [43]. 

A recent systematic review and meta-analysis published in Aug, 2023 indicated that there was moderate certainty of benefit from Escherichia strains, low certainty of benefit from Lactobacillus strains and Lactobacillus plantarum 299V and very low certainty of benefit from Bacillus strains for global symptoms [45]. For abdominal pain, there was low certainty of benefit from Saccharomyces cerevisiae I-3856 and Bifidobacterium strains and very low certainty of benefit from combination probiotics, Lactobacillus, Saccharomyces and Bacillus strains [45] (Table 3). 

Study

Region

Diagnosis

n

(Sample)

Study Design

Interventional

Groups

Duration

Result

[43]

Cape Town,

South Africa

Screeningby gastro-enterologist

(Criteria not specified)

n = 52 where

n = 24, IBS-C and

n = 28,

IBS-D

(24-75 years)

RCT

n = 19, IBS-D and n = 16, IBS-C received Probiotic (Lactobacillus plantarum 299V)

n = 17, Placebo

12 weeks

Lactobacillus profile was significantly different in IBS-C and IBS-D at run-in phase (2 weeks). After probiotic supplementation (8 weeks) and washout period (2 weeks), no statistically significant difference was reported.

[30]

London, U.K.

Rome-III

criteria

n = 104,

IBS-patients

(18-65 years)

Randomized placebo-controlled study

n = 27, Sham diet + placebo

n = 26, sham diet + probiotic,

n = 24, low FODMAP + placebo

n = 27, low FODMAP + probiotic

4 weeks

Abundance of Bifidobacterium sp. was more in faecal samples of patients taking probiotic as compared to those taking placebo (p = 0.019).

[46]

Italy

Rome-III

criteria

n=157,

IBS-C patients

(18-65 years)

Randomized double blind placebo-controlled study

n=50, *F_1

n=50, **F_2

n=50, placebo

 7 discontinued interventions

90 days

Multispecies probiotic supplements are beneficial in IBS-C patients.

Table 3: Research studying the effect of probiotic in irritable bowel syndrome patients, chronologically arranged studies of past ten years.

F_1: 5 × 109 CFU L. acidophilus (30 mg as lyophilized), 5 × 109 CFU L. reuteri (30 mg as lyophilized), 330 mg inulin, 5 mg silica, and 5 mg talc.

F_2: 5 × 109 CFU L. plantarum (12 mg as lyophilized), 5 × 109 CFU L. rhamnosus (20 mg as lyophilized), 5 × 109 CFU B. animalis subsp. lactis (60 mg as lyophilized), 298 mg inulin, 5 mg silica, and 5 mg talc 

Role of physical activity 

In a randomized clinical trial, comparing yoga and low FODMAP diet indicated no statistically significant difference between the interventional groups. However, both the interventions showed statistically significant benefits (p<0.001) in IBS patients when measured after 12 and 24 weeks respectively [28]. Thus, moderate physical activity and proper hydration is also essential part of IBS treatment [22]. In another prospective study conducted on 19,885 IBS patients reported that both light and vigorous activity can mitigate the risk of IBS [47]. Another study reported that running particularly of moderate intensity may be beneficial for improving the symptoms such as bloating, flatulence and constipation in IBS patient [48]. Cochrane database of systematic reviews also reported that physical activity may improve IBS symptoms but there is little to no improvement on the quality of life and abdominal pain [49]. 

Role of sleep 

The pineal gland secretes melatonin in response to darkness which is responsible for maintaining the 24-hour rhythm of human body. It affects the sleep-wake cycle, body temperature, melanin secretion, metabolism and even the defence mechanism. In females it also maintains the menstrual cycle. On an average 7 hours or more of sleep is recommended for adults between 18-60 years of age to maintain optimum health [50]. Numerous studies have reported the effect of sleep in IBS patients, usually the IBS symptoms exacerbate after a night of poor sleeping pattern [51]. 

In a double-blind placebo controlled RCT, the effect of melatonin on IBS patients with and without sleeping disorder was studied. It was concluded that there was significant improvement in IBS score and gastrointestinal symptoms in both the groups [52]. A prospective analysis conducted for 8.45 years by Peking University, Bejing reported 19,885 IBS patients from a sample size of 345,348 participants. They concluded that unhealthy sleeping behaviour was positively associated with worsening IBS symptoms [47].

New approach for population of Asia and other developing countries 

The main goal of IBS treatment is to provide relief from symptoms rather than cure. The factors that exacerbate IBS symptoms need to be identified and conditions that are favourable to control these factors should be implemented [20]. The diet may directly affect the gut microflora and therefore by modifying the dietary factors, improvement can be observed among IBS patients. Low FODMAP diet is highly recommended for IBS patients but in developing countries, these guidelines may not be economically feasible and may also cause nutritional deficiency in long run. Also, there is a huge difference in the diet followed in the Asian countries and the Western world, thereby responsible for the vast variation that can be seen in the prevalence rates, gender differences and manifestation of symptoms [13]. Another important challenge in developing countries with major population having lower socio-economic status may be lack of awareness about IBS and hesitation to visit the health care provider for symptoms which they consider “minor” [53]. Moreover there is need to further improve the diagnostic criteria of IBS in order to make accurate diagnosis and provide benefit to patients who may improve with an approach of extended treatment [11]. 

A current prospective observational study (Sample Size: 204 IBS patients and 400 healthy subjects) conducted in India reported that food intolerance among the individuals vary widely [54]. Hence, there is a need to formulate individualized diet for the patients based on their dietary history, socio-economic status, willingness to change, environmental factors, socio-cultural believes and associated psychological comorbidities. This can only be achieved by a team of well-trained dieticians working in collaboration with doctors, nurses and other health care professionals from clinical nutrition, gastroenterology, psychiatry and associated departments.

Latest recommendations for managing IBS

  • Stay hydrated: Proper hydration is beneficial for regular bowel movements. Atleast 2 liters or more amount of water intake must be maintained by IBS patients. It may be beneficial for IBS-C patients for easy defaecation. It also helps in keeping the IBS-D patients hydrated as they may lose excess water due to excessive evacuation frequency. Severity of IBS, climatic conditions and occupation are some of the factors which influence thirst. 

Although drinking water is the best option but body can be kept hydrated in many ways, some of which are:  drinking lime water solution with little amount of salt, consumption of vegetable soup, drinking coconut water etc.

  • Maintain a regular sleep-wake routine and sleep atleast for an average of 7 hours at night as it boosts both the physical and mental health of an individual.
  • Regular moderate physical activity such as walking or yoga may be beneficial.
  • The food should be chewed properly and must be eaten in a calm manner.
  • Small frequent meals are better tolerated than large meals.
  • Addition of soluble fibers slowly in the diet is recommended to provide relief in IBS patients. These can be on the form of psyllium, citrus fruits like lemon, tangerine or orange, oats etc.
  • Combination of naturally available probiotics and prebiotics may be beneficial in long run for IBS-D patients. For example, intake of banana with butter milk (a fermented drink). Banana will provide energy and electrolytes to IBS-D patients which they have lost due to frequent evacuation. Banana also acts as a prebiotic (food for gut microbes) along with butter milk, which is a milk product made by fermentation having slightly acidic nature and can be digested easily. It promotes the growth of healthy microbes thus improving the overall gut health.

Limitations of the study

This systematic review focuses on three major points of interest i.e, effect of consuming fiber, probiotic and role of diet in irritable bowel syndrome rather than all the outcomes of different studies. Here, the included studies were mainly assessed for their effect on gastrointestinal tract whereas other significant treatments such as psychotherapy, use of medications, cognitive behavioural therapy (CBT) etc. were not analysed. Moreover, this Narrative Review was limited to adult patients and does not include results related to animal trials or studies carried out on children.

Future recommendations

As different countries have different dietary pattern so the dietary guidelines for the IBS patients should be formulated according to the environment, food habits and the resources that are readily available in that region. There must be separate guidelines for western and Asian countries as their dietary habits are completely different according to the environmental factors and cultural differences. There is need to carry out multicentric RCT’s and meta-analysis for in-depth understanding of the role of diet on symptoms and gut microflora of IBS patients.

Also, the wide variety of differences in the diet consumed by population in different geographical regions are affected by the economic differences, climatic conditions, food insecurity issues etc. These points should be kept in mind while formulating dietary guidelines. Thus, a greater number of prospective observational study should be done. which will give a clear picture about dietary pattern which can further be used to carry out studies regarding the impact of consuming various food items and response of IBS patients.

Conclusion

The Narrative Review concludes that there is need to adopt individualized approach for managing food intolerances and IBS symptoms. Although the benefits of low FODMAP diet are known, universalization may not be the best approach. Considering the wide variety of differences in food intolerance among the IBS patients there is a need to carry out more studies. The study emphasis more specific patient-centred approach rather than following generalized dietary guidelines such as low FODMAP diet. Moreover, the effect of diet, probiotics and fiber on the microbiota of IBS patients require research with better experimental designs and results as some of the results are contradictory. 

Proper hydration and regular sleep are beneficial for all the IBS patients around the world. A team of specialists from the department of gastroenterology and dietetics should take the initiative of formulating individualized diet which will decrease the number of patient’s visits thereby reducing the economic burden on the individual and health care system in long run.

Acknowledgements

The authors thank the department of gastroenterology for constant support and cooperation during the research. The authors also thank Dr. Amar Deep Sir, Dept. of Gastroenterology for his valuable suggestions and guidance.

Funding

UGC (University Grants Commission)

Conflict of Interest

None

Reference

  1. Okawa Y, Fukudo S, Sanada H (2019) Specific foods can reduce symptoms of irritable bowel syndrome and functional constipation: A review. Biopsychosoc Med.13:1–6.
  2. Hanel V, Schalla MA, Stengel A (2021) Irritable bowel syndrome and functional dyspepsia in patients with eating disorders - a systematic review. Eur Eat Disord Rev. 29: 692–719.
  3. Mahan LK, Raymond JL (2017) Krause’s Food & The Nutrition Care Process.
  4. Whelan K (2011) Probiotics and prebiotics in the management of irritable bowel syndrome: A review of recent clinical trials and systematic reviews. Curr Opin Clin Nutr Metab Care. 14: 581–7.
  5. Tack J, Stanghellini V, Mearin F, Yiannakou Y, Layer P, et al. (2019) Economic burden of moderate to severe irritable bowel syndrome with constipation in six European countries. BMC Gastroenterol. 19: 69.
  6. Ghoshal UC, Mustafa U, Mukhopadhyay SK (2024) FODMAP meal challenge test: a novel investigation to predict response to low-FODMAP diet in non-constipating irritable bowel syndrome. J Gastroenterol Hepatol. 39: 297-304.
  7. Agarwal N, Spiegel BMR (2011) The Effect of Irritable Bowel Syndrome on Health-Related Quality of Life and Health Care Expenditures. Gastroenterol Clin North Am. 40: 11–9.
  8. Vork L, Keszthelyi D, Van Kuijk SMJ, Quetglas EG, Törnblom H, et al. (2020) Patient-specific stress-abdominal pain interaction in irritable bowel syndrome: An exploratory experience sampling method study. Clin Transl Gastroenterol. 11: 1–8.
  9. Simon MH, Heenan PE, Frampton C, Bayer S, Keenan JI, et al. (2022) Economic living standard and abdominal pain mediate the association between functional gastrointestinal disorders and depression or anxiety. Neurogastroenterol Motil. 35: 1–9.
  10. Fond G, Loundou A, Hamdani N, Boukouaci W, Dargel A, et al. (2014) Anxiety and depression comorbidities in irritable bowel syndrome (IBS): a systematic review and meta-analysis. Eur Arch Psychiatry Clin Neurosci. 264: 651–60.
  11. Hellström PM, Benno P (2019) The Rome IV: Irritable bowel syndrome - A functional disorder. Best Pract Res Clin Gastroenterol. 40–41.
  12. Singh R, Salem A, Nanavati J, Mullin GE (2018) The Role of Diet in the Treatment of Irritable Bowel Syndrome: A Systematic Review. Gastroenterol Clin North Am. 47: 107–37.
  13. 13. El-Salhy M, Patcharatrakul T, Gonlachanvit S (2021) The role of diet in the pathophysiology and management of irritable bowel syndrome. Indian J Gastroenterol. 40: 111–9.
  14. Rajilic-Stojanovic M, Jonkers DM, Salonen A, Hanevik K, Raes J, et al. (2015) Intestinal microbiota and diet in IBS: causes, consequences, or epiphenomena? Am J Gastroenterol. 110: 278–87.
  15. Ghoshal UC, Singh R (2017) Frequency and risk factors of functional gastro-intestinal disorders in a rural Indian population. J Gastroenterol Hepatol. 32: 378–87.
  16. Bennet SMP, Böhn L, Störsrud S, Liljebo T, Collin L, et al. (2018) Multivariate modelling of faecal bacterial profiles of patients with IBS predicts responsiveness to a diet low in FODMAPs. Gut. 67: 872–81.
  17. Orlando A, Tutino V, Notarnicola M, Riezzo G, Linsalata M, et al. (2020) Improved symptom profiles and minimal inflammation in IBS-d patients undergoing a long-term low-fodmap diet: A lipidomic perspective. Nutrients. 12: 1–16.
  18. Reding KW, Cain KC, Jarrett ME, Eugenio MD, Heitkemper MM (2013) Relationship between patterns of alcohol consumption and gastrointestinal symptoms among patients with irritable bowel syndrome. Am J Gastroenterol. 108: 270–6.
  19. Wang Y, Ma W, Mehta R, Nguyen LH, Song M, et al. (2023) Diet and gut microbial associations in irritable bowel syndrome according to disease subtype. Gut Microbes. 15:1–13.
  20. Na W, Sohn C (2023) Food contributing to fermentable monosaccharide, and polyols intake in Korean adults. Nutr Res Pract. 17: 1201–10.
  21. Lee JY, Yau CY, Loh CYL, Lim WS, Teoh SE, et al. (2023) Examining the Association between Coffee Intake and the Risk of Developing Irritable Bowel Syndrome: A Systematic Review and Meta-Analysis. Nutrients. 15: 4745.
  22. Galica AN, Galica R, Dumitrascu DL (2022) Diet, fibers, and probiotics for irritable bowel syndrome. J Med Life. 15: 174–9.
  23. Staudacher HM, Mahoney S, Canale K, Opie RS, Loughman A, et al. (2023) Clinical trial: A Mediterranean diet is feasible and improves gastrointestinal and psychological symptoms in irritable bowel syndrome. Aliment Pharmacol Ther. 1–12.
  24. Russo F, Riezzo G, Orlando A, Linsalata M, D’attoma B, et al. (2022) A Comparison of the Low-FODMAPs Diet and a Tritordeum-Based Diet on the Gastrointestinal Symptom Profile of Patients Suffering from Irritable Bowel Syndrome-Diarrhea Variant (IBS-D): A Randomized Controlled Trial. Nutrients. 14: 1544.
  25. Nordin E, Brunius C, Landberg R, Hellström PM (2022) Fermentable oligo-, di-, monosaccharides, and polyols (FODMAPs), but not gluten, elicit modest symptoms of irritable bowel syndrome: a double-blind, placebo-controlled, randomized three-way crossover trial. Am J Clin Nutr. 115: 344–52.
  26. Tap J, Störsrud S, Le Nevé B, Cotillard A, Pons N, et al. (2021) Diet and gut microbiome interactions of relevance for symptoms in irritable bowel syndrome. Microbiome. 9: 1–13.
  27. Zhang Y, Feng L, Wang X, Fox M, Luo L, et al. (2021) Low fermentable oligosaccharides, disaccharides, monosaccharides, and polyols diet compared with traditional dietary advice for diarrhea-predominant irritable bowel syndrome: A parallel-group, randomized controlled trial with analysis of clinical and micr. Am J Clin Nutr. 113:1531–45.
  28. Schumann D, Langhorst J, Dobos G, Cramer H (2018) Randomised clinical trial: yoga vs a low-FODMAP diet in patients with irritable bowel syndrome. Aliment Pharmacol Ther. 47: 203–11.
  29. Tigchelaar EF, Mujagic Z, Zhernakova A, Hesselink MAM, Meijboom S, et al. (2017) Habitual diet and diet quality in Irritable Bowel Syndrome: A case-control study. Neurogastroenterol Motil. 29.
  30. Staudacher HM, Lomer MCE, Farquharson FM, Louis P, Fava F, et al. (2017) A Diet Low in FODMAPs Reduces Symptoms in Patients With Irritable Bowel Syndrome and A Probiotic Restores Bifidobacterium Species: A Randomized Controlled Trial. Gastroenterology. 153: 936–47.
  31. Moayyedi P, Quigley EMM, Lacy BE, Lembo AJ, Saito YA, et al. (2014) The effect of fiber supplementation on irritable bowel syndrome: a systematic review and meta-analysis. Am J Gastroenterol. 109: 1367–74.
  32. Bijkerk CJ, De Wit NJ, Muris JWM, Whorwell PJ, Knottnerus JA, et.al. (2009) Soluble or insoluble fibre in irritable bowel syndrome in primary care? Randomised placebo controlled trial. BMJ. 339: 613–5.
  33. Zhu JZ, Yan TL, Yu CH, Wan XY, Wang YM, et al. (2014) Is national socioeconomic status related to prevalence of irritable bowel syndrome? J Gastroenterol Hepatol. 29: 1595–602.
  34. Fukudo S, Okumura T, Inamori M, Okuyama Y, Kanazawa M, et al. (2021) Evidence-based clinical practice guidelines for irritable bowel syndrome 2020. J Gastroenterol. 56: 193–217.
  35. Zhou J, Ho V (2023) Role of Baseline Gut Microbiota on Response to Fiber Intervention in Individuals with Irritable Bowel Syndrome. Nutrients. 15: 4786.
  36. ICMR-NIN (2020) Recommended Dietary Allowances & Estimated Average Requirements for Indians - 2020.
  37. Yan R, Andrew L, Marlow E, Kunaratnam K, Devine A, et al. (2021) Dietary Fibre Intervention for Gut Microbiota, Sleep, and Mental Health in Adults with Irritable Bowel Syndrome: A Scoping Review. Nutrients. 13: 1–19.
  38. Barboi O-BOB, Chirila I, Ciortescu I, Anton C, Drug V-LVL (2022) Inulin, Choline and Silymarin in the Treatment of Irritable Bowel Syndrome with Constipation—Randomized Case-Control Study. J Clin Med. 11: 2248.
  39. Cockerell KM, Watkins ASM, Reeves LB, Goddard L, Lomer MCE (2012) Effects of linseeds on the symptoms of irritable bowel syndrome: A pilot randomised controlled trial. J Hum Nutr Diet. 25: 435–43.
  40. Rees G, Davies J, Thompson R, Parker M, Liepins P (2005) Randomised-controlled trial of a fibre supplement on the symptoms of irritable bowel syndrome. J R Soc Promot Health. 125: 30–4.
  41. Distrutti E, Monaldi L, Ricci P, Fiorucci S (2016) Gut microbiota role in irritable bowel syndrome: New therapeutic strategies. World J Gastroenterol. 22: 2219–41.
  42. Carroll IM, Ringel-Kulka T, Keku TO, Chang YH, Packey CD, et al. (2011) Molecular analysis of the luminal- and mucosal-associated intestinal microbiota in diarrhea-predominant irritable bowel syndrome. Am J Physiol - Gastrointest Liver Physiol. 301: 799–807.
  43. Stevenson C, Blaauw R, Fredericks E, Visser J, Roux S (2021) Probiotic effect and dietary correlations on faecal microbiota profiles in irritable bowel syndrome Probiotic effect and dietary correlations on faecal microbiota pro fi les in irritable bowel syndrome. South African J Clin Nutr. 34: 84–9.
  44. Floch MH, Walker WA, Sanders ME, Nieuwdorp M, Kim AS, et al. (2015) Recommendations for Probiotic Use—2015 Update. J Clin Gastroenterol. 49: 69–73.
  45. Goodoory VC, Khasawneh M, Black CJ, Quigley EMM, Moayyedi P, et al. (2023) Efficacy of Probiotics in Irritable Bowel Syndrome: Systematic Review and Meta-analysis. Gastroenterology. 165: 1206–18.
  46. Mezzasalma V, Manfrini E, Ferri E, Sandionigi A, La Ferla B, et al. (2016) A Randomized, Double-Blind, Placebo-Controlled Trial: The Efficacy of Multispecies Probiotic Supplementation in Alleviating Symptoms of Irritable Bowel Syndrome Associated with Constipation. Biomed Res Int.
  47. Gao X, Tian S, Huang N, Sun G, Huang T (2023) Associations of daily sedentary behavior, physical activity, and sleep with irritable bowel syndrome: A prospective analysis of 362,193 participants. J Sport Heal Sci.1–9.
  48. Baart AM, Mensink M, Witteman BJM (2023) The impact of running on gastrointestinal symptoms in patients with irritable bowel syndrome. Neurogastroenterol Motil. 1–11.
  49. Nunan D, Cai T, Gardener AD, Ordóñez-Mena JM, Roberts NW, et al. (2022) Physical activity for treatment of irritable bowel syndrome. Cochrane Database Syst Rev. 6: 11497.
  50. Watson NF, Badr MS, Belenky G, Bliwise DL, Buxton OM, et al. (2015) Recommended amount of sleep for a healthy adult: A joint consensus statement of the American Academy of Sleep Medicine and Sleep Research Society. Sleep. 38: 843–4.
  51. Orr WC, Fass R, Sundaram SS, Scheimann AO (2020) The effect of sleep on gastrointestinal functioning in common digestive diseases. Lancet Gastroenterol Hepatol. 5: 616–24.
  52. Faghih Dinevari M, Jafarzadeh F, Jabbaripour Sarmadian A, Abbasian S, Nikniaz Z, et al. (2023) The effect of melatonin on irritable bowel syndrome patients with and without sleep disorders: a randomized double-blinded placebo-controlled trial study. BMC Gastroenterol. 23: 1–11.
  53. Mahmood K, Riaz R, Salman Ul Haq M, Hamid K, Jawed H (2020) Association of cigarette smoking with irritable bowel syndrome: A cross-sectional study. Med J Islam Repub Iran.34:1–7.
  54. Abraham P, Dhoble P, Desai D, Joshi A, Gupta T (2023) Self-reported food intolerances in an Indian population: Need for individualization rather than a universal low-FODMAP diet. JGH Open. 7:772–6.

Citation: Saroj S, Gupta K, Rungta S, Kumar N, Bharti D, (2025) Unravelling the Digestive Dilemma: Investigating Dietary Influence on Irritable Bowel Syndrome through Narrative Review. HSOA J Gastroenterol Hepatology Res 9: 055

Copyright: © 2025  Shraddha Saroj, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


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