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Abbasnezhad A, Samadi M, Mohammadi S, Darabi Z, Yarizadeh H, Fazeli Moghadam E. The Association between Adherence to the MIND Diet and Depression and Anxiety in Irritable Bowel Syndrome Patients. JNFS 2026; 11 (1) :26-35
URL: http://jnfs.ssu.ac.ir/article-1-1384-en.html
URL: http://jnfs.ssu.ac.ir/article-1-1384-en.html
Amir Abbasnezhad 
, Mehnoosh Samadi , Salman Mohammadi , Zahra Darabi , Habib Yarizadeh , Ezatollah Fazeli Moghadam *
, Mehnoosh Samadi , Salman Mohammadi , Zahra Darabi , Habib Yarizadeh , Ezatollah Fazeli Moghadam *
Nutritional Health Research Center, School of Health and Nutrition, Lorestan University of Medical Sciences, Khorramabad, Iran
Keywords: Irritable Bowel Syndrome, MIND diet, Anxiety, Depression, Cross-sectional, Psychological disorders.
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1 Urmia Milad International Hospital. Urmia, Iran; 2 Nutritional Sciences Department, School of Nutrition. Sciences and Food Technology, Kermanshah University of Medical Sciences, Kermanshah, Iran; 3 Nutritional Health Research Center, School of Health and Nutrition, Lorestan University of Medical Sciences, Khorramabad, Iran; 4 Social Determinants of Health Research Center, Saveh University of Medical Sciences, Saveh, Iran.
Introduction
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The Association between Adherence to the MIND Diet and Depression and Anxiety in Irritable Bowel Syndrome Patients
Amir Abbasnezhad; PhD1, Mehnoosh Samadi; PhD2, Salman Mohammadi; PhD3, Zahra Darabi; PhD3,
Habib Yarizadeh; PhD4, Ezatollah Fazeli Moghadam; PhD*3
Amir Abbasnezhad; PhD1, Mehnoosh Samadi; PhD2, Salman Mohammadi; PhD3, Zahra Darabi; PhD3,
Habib Yarizadeh; PhD4, Ezatollah Fazeli Moghadam; PhD*3
1 Urmia Milad International Hospital. Urmia, Iran; 2 Nutritional Sciences Department, School of Nutrition. Sciences and Food Technology, Kermanshah University of Medical Sciences, Kermanshah, Iran; 3 Nutritional Health Research Center, School of Health and Nutrition, Lorestan University of Medical Sciences, Khorramabad, Iran; 4 Social Determinants of Health Research Center, Saveh University of Medical Sciences, Saveh, Iran.
| ARTICLE INFO | ABSTRACT | |
| ORIGINAL ARTICLE | Background: Irritable Bowel Syndrome (IBS) is one of the most common functional gastrointestinal disorders. Accordingly, this study aims to investigate the association between adherence to the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet and the odds of anxiety and depression among patients with IBS. Methods: This multicenter cross-sectional study was conducted from 2021 to 2023 in three university-affiliated centers in Iran. A total of 262 IBS patients aged 18–60 (168 males, 94 females; mean age 29.72 ± 10.19 years) were recruited based on the Rome III criteria. Dietary intake was assessed using a validated 168-item food frequency questionnaire, and MIND diet scores were calculated. Anxiety was measured using the Hospital Anxiety and Depression Scale (HADS), and depression was assessed using the Patient Health Questionnaire-9 (PHQ-9). Logistic regression analyses were performed to estimate the odds ratios (ORs) for anxiety and depression across MIND diet score tertiles, adjusting for potential confounders. Results: Higher adherence to the MIND diet was significantly associated with lower odds of both anxiety (OR: 0.69, 95% CI: 0.53–0.89, P=0.005) and depression (OR: 0.73, 95% CI: 0.59–0.91, P=0.006) in IBS patients. Additionally, an inverse relationship was observed between MIND diet adherence and the severity of IBS symptoms (OR: 0.70, 95% CI: 0.52–0.94, P=0.02). Conclusion: Greater adherence to the MIND diet was associated with reduced odds of anxiety and depression, as well as lower severity of IBS symptoms. Further prospective and interventional studies are warranted to confirm these findings. | |
| Article history: Received: 4 Jul 2025 Revised: 23 Sep 2025 Accepted: 21 Oct 2025 |
||
| *Corresponding author: ztfazeli@yahoo.com Nutritional Health Research Center, School of Health and Nutrition, Lorestan University of Medical Sciences, Khorramabad, Iran. Postal code: 6819789741 Tel: +98 937 9464400 |
||
| Keywords: Irritable Bowel Syndrome; MIND diet; Anxiety; Depression; Cross-sectional; Psychological disorders. |
Introduction
Irritable Bowel Syndrome (IBS) is among the most prevalent functional bowel disorders; it is a type of functional gastrointestinal disorder (FGID) that involves persistent abdominal pain or discomfort along with changes in bowel habits (Shaikh et al., 2023). The meta-analysis results indicated that the global prevalence of IBS was 9.2% (Oka et al., 2020). In Iran, reported prevalence rates of IBS ranged from 1.1% to 25%, with a higher occurrence observed among women (Jahangiri et al., 2012).
IBS indeed has a significant impact on healthcare systems (Canavan et al., 2014). Research shows that patients with IBS often experience higher levels of depression and anxiety compared to those without IBS (Zamani et al., 2019). This psychological distress can exacerbate gastrointestinal symptoms, creating a challenging cycle for patients (Midenfjord et al., 2019). In humans, several types of brain networks have been identified. Alterations in neural networks related to IBS have provided plausible neurobiological substrates for various information-processing abnormalities observed in patients with IBS (Mayer et al., 2023). Results of a meta-analysis have shown that individuals with IBS experience anxiety compared to the general population (Lee et al., 2017).
Several factors contribute to the pathogenesis of IBS, including dysregulated brain-gut communication (brain-gut axis), alterations in the gut microbiome, previous infections, psychological stress, dietary influences, and both pre- and postnatal factors (Shaikh et al., 2023).
Diet can influence both irritable bowel syndrome symptoms and mental health disorders (Chen et al., 2024, Grajek et al., 2022). A 2024 study found that consuming a low- fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAP) diet combined with prebiotics reduced depression, anxiety, IBS, quality of life scale and the severity of symptoms in patients with IBS (Ustaoğlu et al., 2024). Previous studies have demonstrated that DASH and Mediterranean diets positively impact quality of life, as well as anxiety and depression (Shiraseb et al., 2023, Tan et al., 2024). The Mediterranean-DASH Intervention for Neurodegenerative Delay diet (MIND) diet, a combination of the Mediterranean and DASH diets, effectively bridges the gaps by integrating the strengths of both. It focuses on specific dietary components that enhance brain health while avoiding harmful food choices. The MIND diet includes ten components that promote brain health: green leafy vegetables, other vegetables, nuts, berries, beans, whole grains, fish, poultry, olive oil, and wine. It avoids five unhealthy components: red meats, butter and stick margarine, cheese, pastries and sweets, and fried or fast foods (Kheirouri and Alizadeh, 2022). Studies on the association between the MIND diet and mental disorders have yielded inconsistent results, with some finding an inverse relationship and others finding no significant association (Seifollahi et al., 2024, Torabynasab et al., 2023).
In this study, the authors aim to investigate the relationship between the Mind diet and depression, as well as anxiety in Iranian patients with IBS.
Materials and Methods
Study design and participant enrollment
This multicenter cross-sectional study was conducted from 2021 to 2023 at Lorestan University of Medical Sciences (Khorramabad), Urmia University of Medical Sciences and Kermanshah University of Medical Sciences. In this study, IBS patients aged 18 to 60 years old who were referred to the specialized clinics of the mentioned universities were selected from each center based on the Rome III diagnostic criteria with the approval of the gastroenterology subspecialist using the convenience sampling method. These criteria define IBS as recurrent abdominal pain or discomfort occurring at least three days per month during the past three months, accompanied by at least two of the following: (1) improvement of symptoms with defecation, (2) onset associated with a change in stool frequency, and (3) onset associated with a change in stool form. Individuals with underlying conditions such as diabetes, liver or kidney dysfunction, cardiovascular disease, cancer, coeliac disease, inflammatory bowel disease, or other digestive disorders, as well as those with a history of abdominal surgery, pregnancy, breastfeeding, special diets, smoking, or alcohol consumption, were excluded from the study.
Measurements
The dietary intake was assessed using the previously validated and reliable 168-item Food Frequency Questionnaire (FFQ) (Bawadi et al., 2021). In this questionnaire, there is a standard size for each food item, which is designed according to the Willette method.
First, during the face-to-face interview, the average size of each food item was explained, and then people were asked to report the frequency of consumption of each food item over the past year. Depending on the type of food consumed, the frequency of consumption per day, week or month, was asked. The amounts reported by the subjects for each food item were converted to grams per day using the home comparison guide book, and finally, the exact amounts of energy, micronutrients, and macronutrients consumed by each participant were calculated using the Nutritionist IV (N4) software.
MIND diet assessment: The assessment of dietary intake was conducted through face-to-face interviews using a validated 168-item semi-quantitative FFQ tailored for Iran. For this study, specific nutritional components from the FFQ, detailed in Table 1, were used to compute MIND diet scores. Out of the original 15 dietary components in the MIND diet, 10 were classified as beneficial to brain health-these include green leafy vegetables, other vegetables, nuts, berries, beans, whole grains, fish, poultry, olive oil, and wine—while 5 were deemed harmful: red meats, butter and stick margarine, cheese, pastries, and sweets, and fried/fast food. In this study, the authors utilized a modified MIND diet scoring system adjusted for Iranian dietary customs by excluding wine, consumption of which is not legally permitted. Scoring for the MIND diet was applied to the remaining 14 food groups. Participants were divided into tertile categories based on their intake levels. Participants in the lowest tertile of brain-healthy foods received a score of 0, those in the middle tertile received 0.5, and individuals in the highest tertile were given a score of 1. Conversely, the unhealthy food groups were evaluated in reverse. The total MIND diet score ranged from 0 to 14, summing the scores from all dietary components.
IBS indeed has a significant impact on healthcare systems (Canavan et al., 2014). Research shows that patients with IBS often experience higher levels of depression and anxiety compared to those without IBS (Zamani et al., 2019). This psychological distress can exacerbate gastrointestinal symptoms, creating a challenging cycle for patients (Midenfjord et al., 2019). In humans, several types of brain networks have been identified. Alterations in neural networks related to IBS have provided plausible neurobiological substrates for various information-processing abnormalities observed in patients with IBS (Mayer et al., 2023). Results of a meta-analysis have shown that individuals with IBS experience anxiety compared to the general population (Lee et al., 2017).
Several factors contribute to the pathogenesis of IBS, including dysregulated brain-gut communication (brain-gut axis), alterations in the gut microbiome, previous infections, psychological stress, dietary influences, and both pre- and postnatal factors (Shaikh et al., 2023).
Diet can influence both irritable bowel syndrome symptoms and mental health disorders (Chen et al., 2024, Grajek et al., 2022). A 2024 study found that consuming a low- fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAP) diet combined with prebiotics reduced depression, anxiety, IBS, quality of life scale and the severity of symptoms in patients with IBS (Ustaoğlu et al., 2024). Previous studies have demonstrated that DASH and Mediterranean diets positively impact quality of life, as well as anxiety and depression (Shiraseb et al., 2023, Tan et al., 2024). The Mediterranean-DASH Intervention for Neurodegenerative Delay diet (MIND) diet, a combination of the Mediterranean and DASH diets, effectively bridges the gaps by integrating the strengths of both. It focuses on specific dietary components that enhance brain health while avoiding harmful food choices. The MIND diet includes ten components that promote brain health: green leafy vegetables, other vegetables, nuts, berries, beans, whole grains, fish, poultry, olive oil, and wine. It avoids five unhealthy components: red meats, butter and stick margarine, cheese, pastries and sweets, and fried or fast foods (Kheirouri and Alizadeh, 2022). Studies on the association between the MIND diet and mental disorders have yielded inconsistent results, with some finding an inverse relationship and others finding no significant association (Seifollahi et al., 2024, Torabynasab et al., 2023).
In this study, the authors aim to investigate the relationship between the Mind diet and depression, as well as anxiety in Iranian patients with IBS.
Materials and Methods
Study design and participant enrollment
This multicenter cross-sectional study was conducted from 2021 to 2023 at Lorestan University of Medical Sciences (Khorramabad), Urmia University of Medical Sciences and Kermanshah University of Medical Sciences. In this study, IBS patients aged 18 to 60 years old who were referred to the specialized clinics of the mentioned universities were selected from each center based on the Rome III diagnostic criteria with the approval of the gastroenterology subspecialist using the convenience sampling method. These criteria define IBS as recurrent abdominal pain or discomfort occurring at least three days per month during the past three months, accompanied by at least two of the following: (1) improvement of symptoms with defecation, (2) onset associated with a change in stool frequency, and (3) onset associated with a change in stool form. Individuals with underlying conditions such as diabetes, liver or kidney dysfunction, cardiovascular disease, cancer, coeliac disease, inflammatory bowel disease, or other digestive disorders, as well as those with a history of abdominal surgery, pregnancy, breastfeeding, special diets, smoking, or alcohol consumption, were excluded from the study.
Measurements
The dietary intake was assessed using the previously validated and reliable 168-item Food Frequency Questionnaire (FFQ) (Bawadi et al., 2021). In this questionnaire, there is a standard size for each food item, which is designed according to the Willette method.
First, during the face-to-face interview, the average size of each food item was explained, and then people were asked to report the frequency of consumption of each food item over the past year. Depending on the type of food consumed, the frequency of consumption per day, week or month, was asked. The amounts reported by the subjects for each food item were converted to grams per day using the home comparison guide book, and finally, the exact amounts of energy, micronutrients, and macronutrients consumed by each participant were calculated using the Nutritionist IV (N4) software.
MIND diet assessment: The assessment of dietary intake was conducted through face-to-face interviews using a validated 168-item semi-quantitative FFQ tailored for Iran. For this study, specific nutritional components from the FFQ, detailed in Table 1, were used to compute MIND diet scores. Out of the original 15 dietary components in the MIND diet, 10 were classified as beneficial to brain health-these include green leafy vegetables, other vegetables, nuts, berries, beans, whole grains, fish, poultry, olive oil, and wine—while 5 were deemed harmful: red meats, butter and stick margarine, cheese, pastries, and sweets, and fried/fast food. In this study, the authors utilized a modified MIND diet scoring system adjusted for Iranian dietary customs by excluding wine, consumption of which is not legally permitted. Scoring for the MIND diet was applied to the remaining 14 food groups. Participants were divided into tertile categories based on their intake levels. Participants in the lowest tertile of brain-healthy foods received a score of 0, those in the middle tertile received 0.5, and individuals in the highest tertile were given a score of 1. Conversely, the unhealthy food groups were evaluated in reverse. The total MIND diet score ranged from 0 to 14, summing the scores from all dietary components.
| Table 1. Components of the MIND diet score. | ||
| Brain-Healthy foods score | ||
| 1 | Green leafy vegetables | Lettuce and greens |
| 2 | Other vegetables | Cucumber, tomatoes, tomato sauce, carrot, green beans, onion, potatoes, capsicum, peas, eggplant, cabbage, and mushrooms |
| 3 | Berries | Strawberries and berries |
| 4 | Nuts | Walnuts, pistachios, hazelnuts, almonds, peanuts, and seeds |
| 5 | Whole grains | Whole grains |
| 6 | Fish | Fish |
| 7 | Beans | Lentils, beans, chickpeas, mung beans, and cotyledons |
| 8 | Poultry | Chicken |
| 9 | Olive oil | Olive oil |
| Brain-unhealthy foods score | ||
| 10 | Butter and margarine | Butter, cream, and hydrogenated fats |
| 11 | Cheese | Cheese |
| 12 | Red meat and products | Red meat, hamburger, and sausages |
| 13 | Fast fried foods | French fries and pizza |
| 14 |
Pastries and sweets |
Confections, ice cream, biscuit, cake, chocolate, candy, gaz (an Iranian confectionery made of sugar, nuts, and tamarisk), and gooshfil (an Iranian confectionery made of white flour and sugar) |
Severity of IBS symptoms: The Extra-Intestinal Symptoms Severity Scale (EISSS) was used to assess the severity of extra-intestinal IBS symptoms. This instrument consists of 15 seven-item questions (from never to always) that assess non-intestinal symptoms associated with IBS, including vomiting and nausea, early satiety, headache, back pain, fatigue, excessive flatulence, heartburn, urgency to defecate, feeling of incomplete bowel movement, urgency to urinate, thigh pain, muscle or joint pain, and feeling full after eating. The alternatives of sometimes to always experiencing the feeling were considered as the presence of a sign (Gholamrezaei et al., 2011).
Severity of depression symptoms: The Patient Health Questionnaire (PHQ-9) was used to assess depression severity. This questionnaire consists of 9 items and ranges from 0 to 27 regarding the intensity of depression symptoms. A score of less than 5 indicates mental health and the absence of depression, while a score between 5 and 9 indicates mild depression. Scores between 10 and 14 or above 15 represent moderate to severe depressive states, respectively. Individuals with a depression score of 10 or higher were considered depressed patients (Kroenke et al., 2001).
Anxiety status: The Hospital Anxiety and Depression Scale (HADS) questionnaire was used to assess participants' anxiety status. This questionnaire consists of 14 self-reported questions, each scored on a 4-point Likert scale ranging from 0 to 3. A participant's total score would range from 0 to 21. Lower scores indicate less anxiety, and individuals with an anxiety score of 11 or higher were considered depressed (de Lemos Zingano et al., 2019).
Anthropometric measurements: Anthropometric measurements including height and weight were measured using stadiometer with an accuracy of 0.1 cm and a digital scale with an accuracy of 100 grams. The BMI was calculated by dividing the body weight (kg) by the height (m2) (Ramstrand et al., 2011).
Physical activity level: The physical activity of the participants was assessed using the International Physical Activity Questionnaire (IPAQ). This questionnaire collected information about physical activity during working hours, commuting, household chores, and free time during the past 7 days. Then, according to the standard instructions, the total metabolic equivalent score (MetS) was calculated and the participants were classified into groups of low (up to 600 met/min/week), moderate (600 to 3000 met/min/week), and high (at least 3000 met min/week) activity levels (Mohammadi et al., 2022).
Ethical considerations
Severity of depression symptoms: The Patient Health Questionnaire (PHQ-9) was used to assess depression severity. This questionnaire consists of 9 items and ranges from 0 to 27 regarding the intensity of depression symptoms. A score of less than 5 indicates mental health and the absence of depression, while a score between 5 and 9 indicates mild depression. Scores between 10 and 14 or above 15 represent moderate to severe depressive states, respectively. Individuals with a depression score of 10 or higher were considered depressed patients (Kroenke et al., 2001).
Anxiety status: The Hospital Anxiety and Depression Scale (HADS) questionnaire was used to assess participants' anxiety status. This questionnaire consists of 14 self-reported questions, each scored on a 4-point Likert scale ranging from 0 to 3. A participant's total score would range from 0 to 21. Lower scores indicate less anxiety, and individuals with an anxiety score of 11 or higher were considered depressed (de Lemos Zingano et al., 2019).
Anthropometric measurements: Anthropometric measurements including height and weight were measured using stadiometer with an accuracy of 0.1 cm and a digital scale with an accuracy of 100 grams. The BMI was calculated by dividing the body weight (kg) by the height (m2) (Ramstrand et al., 2011).
Physical activity level: The physical activity of the participants was assessed using the International Physical Activity Questionnaire (IPAQ). This questionnaire collected information about physical activity during working hours, commuting, household chores, and free time during the past 7 days. Then, according to the standard instructions, the total metabolic equivalent score (MetS) was calculated and the participants were classified into groups of low (up to 600 met/min/week), moderate (600 to 3000 met/min/week), and high (at least 3000 met min/week) activity levels (Mohammadi et al., 2022).
Ethical considerations
The ethical committee of Lorestan University of Medical Sciences approved the study (code number:IR.IUMS.REC.1399.308). The written informed consent was signed by all the participants before the beginning of the study. This study was performed in line with the ethical principles established by the World Medical Association in the Declaration of Helsinki.
Data analysis
The Kolmogorov–Smirnov test was used to assess the normality of the data distribution. One-way analysis of variance (ANOVA) was employed to analyze differences in continuous variables across different quantiles of the MIND diet. For qualitative variables, variations among MIND diet quantiles were examined using cross-tabulation. Logistic regression was performed to examine prevalence ratio of psychological disorders in IBS patients in a crude model and three justified models; they included the crude model which was justified for no variable, model-1 justified for age and gender, model-2 additionally justified for BMI and total energy intake, and model-3 which was additionally justified for educational status, and marital status. A significance level of 0.05 or lower was established for all tests. All statistical analyses were performed using IBM SPSS version 22.0 (SPSS, Chicago, IL, USA).
Results
Study population
A total of 262 IBS patients were involved in this study (168 males, 94 females), and the average age was 29.72±10.19 years. The mean body weight and BMI were 72.66±12.06 kg and 25.84±3.87 kg/m², respectively. The differences in age, BMI and body weight across the various MIND score quantiles are presented in Table 2.
Food intake
Table 3 illustrates the participants' food consumption across different quantiles of the MIND score. The results from the ANOVA test revealed significant differences in all food groups among these quantiles (P<0.01).
Qualitative characteristics
Table 4 shows how the participants' qualitative characteristics relate to the quantiles of the MIND diet score. A significant correlation was observed between the MIND diet score quantiles and factors such as sex, educational status, marital status, job status, smoking habits, depression status, anxiety status and severity of IBS symptoms (P<0.001).
MIND diet, depression and anxiety
According to the findings, there was a significant correlation between anxiety status and MIND score (Spearman correlation r: - 0.21, P=0.003). Prevalence ratio of anxiety and depression among IBS patients based on MIND score quintiles is presented in Table 5. As shown in this table, A significant negative relationship was observed between the MIND diet and the prevalence ratio of anxiety (95 % CI: 0.69, 0.53 to 0.89, P=0.005) and depression (95 % CI: 0.73, 0.59 to 0.91, P=0.006) in individuals with IBS after adjusting for confounding variables such as age, sex, BMI, total energy intake, educational status, and marital status.
MIND diet and severity of IBS symptoms
The binary logistic regression model showed a significant inverse relationship between the MIND diet and the severity of IBS symptoms (OR 0.70, 95% CI 0.52 to 0.94, P=0.02) in the IBS group, even after controlling for confounding variables (age, gender, total energy intake, physical activity, educational status, and marital status). However, this association was not observed in the healthy group (Table 6).
Discussion
To the best of the authors’ knowledge, this is the first study to investigate the relationship between the MIND diet and depression and anxiety in individuals with irritable bowel syndrome. Results of this study showed that there was a negative relationship between the MIND diet and the prevalence ratio of depression and anxiety in people with IBS.
The well-documented co-occurrence of IBS with anxiety and depression is widely recognized. Both conditions share various biological and psychosocial mechanisms, many of which lead to a disrupted gut-brain axis (Staudacher et al., 2021). Meta-analyses have demonstrated that individuals with IBS exhibit higher levels of anxiety and depression compared to healthy controls (Zamani et al., 2019).
The Kolmogorov–Smirnov test was used to assess the normality of the data distribution. One-way analysis of variance (ANOVA) was employed to analyze differences in continuous variables across different quantiles of the MIND diet. For qualitative variables, variations among MIND diet quantiles were examined using cross-tabulation. Logistic regression was performed to examine prevalence ratio of psychological disorders in IBS patients in a crude model and three justified models; they included the crude model which was justified for no variable, model-1 justified for age and gender, model-2 additionally justified for BMI and total energy intake, and model-3 which was additionally justified for educational status, and marital status. A significance level of 0.05 or lower was established for all tests. All statistical analyses were performed using IBM SPSS version 22.0 (SPSS, Chicago, IL, USA).
Results
Study population
A total of 262 IBS patients were involved in this study (168 males, 94 females), and the average age was 29.72±10.19 years. The mean body weight and BMI were 72.66±12.06 kg and 25.84±3.87 kg/m², respectively. The differences in age, BMI and body weight across the various MIND score quantiles are presented in Table 2.
Food intake
Table 3 illustrates the participants' food consumption across different quantiles of the MIND score. The results from the ANOVA test revealed significant differences in all food groups among these quantiles (P<0.01).
Qualitative characteristics
Table 4 shows how the participants' qualitative characteristics relate to the quantiles of the MIND diet score. A significant correlation was observed between the MIND diet score quantiles and factors such as sex, educational status, marital status, job status, smoking habits, depression status, anxiety status and severity of IBS symptoms (P<0.001).
MIND diet, depression and anxiety
According to the findings, there was a significant correlation between anxiety status and MIND score (Spearman correlation r: - 0.21, P=0.003). Prevalence ratio of anxiety and depression among IBS patients based on MIND score quintiles is presented in Table 5. As shown in this table, A significant negative relationship was observed between the MIND diet and the prevalence ratio of anxiety (95 % CI: 0.69, 0.53 to 0.89, P=0.005) and depression (95 % CI: 0.73, 0.59 to 0.91, P=0.006) in individuals with IBS after adjusting for confounding variables such as age, sex, BMI, total energy intake, educational status, and marital status.
MIND diet and severity of IBS symptoms
The binary logistic regression model showed a significant inverse relationship between the MIND diet and the severity of IBS symptoms (OR 0.70, 95% CI 0.52 to 0.94, P=0.02) in the IBS group, even after controlling for confounding variables (age, gender, total energy intake, physical activity, educational status, and marital status). However, this association was not observed in the healthy group (Table 6).
Discussion
To the best of the authors’ knowledge, this is the first study to investigate the relationship between the MIND diet and depression and anxiety in individuals with irritable bowel syndrome. Results of this study showed that there was a negative relationship between the MIND diet and the prevalence ratio of depression and anxiety in people with IBS.
The well-documented co-occurrence of IBS with anxiety and depression is widely recognized. Both conditions share various biological and psychosocial mechanisms, many of which lead to a disrupted gut-brain axis (Staudacher et al., 2021). Meta-analyses have demonstrated that individuals with IBS exhibit higher levels of anxiety and depression compared to healthy controls (Zamani et al., 2019).
| Table 2. Number of participants across quantiles of MIND diet. | ||||||
| Variables | Q1 | Q2 | Q3 | Q4 | Q5 | P-valuea |
| Gender Male |
71 | 90 | 61 | 111 | 66 | <0.001 |
| Female | 78 | 78 | 50 | 61 | 100 | |
| Group Case |
79 | 65 | 57 | 71 | 43 | <0.001 |
| Control | 95 | 112 | 78 | 140 | 136 | |
| Smoking Smoker |
63 | 85 | 52 | 86 | 61 | <0.001 |
| Non-smoker | 104 | 61 | 69 | 87 | 109 | |
| Quit smoking | 1 | 16 | 3 | 13 | 9 | |
| Education Illiterate |
21 | 14 | 5 | 18 | 32 | <0.001 |
| Under high school diploma | 22 | 11 | 17 | 12 | 12 | |
| High school diploma | 37 | 33 | 26 | 35 | 33 | |
| Educated | 77 | 107 | 73 | 136 | 96 | |
| Job status Unemployed |
47 | 54 | 32 | 67 | 33 | <0.001 |
| Housekeeper | 53 | 59 | 62 | 89 | 90 | |
| Employee | 50 | 39 | 32 | 27 | 42 | |
| Retired | 0 | 0 | 0 | 1 | 0 | |
| Farmer | 7 | 10 | 0 | 7 | 0 | |
| Marital status Single |
85 | 87 | 54 | 111 | 122 | <0.001 |
| Married | 85 | 82 | 71 | 82 | 47 | |
| a: Obtained from Chi-square test | ||||||
| Table 3. Food groups across quantiles of MIND diet. | ||||||
| Food groups | Q1 | Q 2 | Q 3 | Q 4 | Q 5 | P-valuea |
| Green leafy vegetables | 42.33±20.69 |
28.16±19.15 |
22.26±13.35 |
18.51±14.04 |
10.18±8.78 |
<0.001 |
| Other vegetables | 341.13±199.84 | 263.77±201.39 | 197.01±142.22 | 165.59±106.55 | 108.88±108.34 | <0.001 |
| Berries | 6.83±0.49 | 4.83±0.36 | 1.09±0.09 | 1.24±0.09 | 0.79±0.05 | <0.001 |
| Nuts | 11.53±15.86 | 3.17±3.21 | 2.67±2.46 | 2.55±2.22 | 0.98±1.59 | <0.001 |
| Whole grains | 34.45±29.75 | 21.15±19.88 | 24.52±21.42 | 15.14±15.64 | 11.55±14.45 | <0.001 |
| Fish | 8.09±7.86 | 6.02±8.12 | 2.72±4.13 | 3.96±5.70 | 0.95±1.19 | <0.001 |
| Beans | 31.22±27.44 | 18.28±13.71 | 22.87±20.61 | 17.23±16.25 | 11.32±9.56 | <0.001 |
| Poultry | 52.43±54.26 | 38.92±27.67 | 26.15±18.46 | 28.80±25.17 | 17.95±20.51 | <0.001 |
| Olive oil | 0.22±1.02 | 0.08±0.47 | 0.06±0.31 | 0.04±0.23 | 0.00±0.03 | 0.002 |
| Butter and margarine | 18.93±33.52 | 5.70±8.19 | 4.61±7.53 | 1.70±2.79 | 0.71±1.44 | <0.001 |
| Cheese | 25.44±29.88 | 19.90±21.63 | 13.37±17.14 | 9.67±11.13 | 5.00±7.73 | <0.001 |
| Red meat and products | 44.21±61.26 |
27.13±27.09 |
19.27±19.73 |
12.68±12.52 |
6.42±9.76 |
<0.001 |
| Fast fried foods | 23.50±15.99 | 19.02±13.16 | 14.83±13.68 | 9.64±9.57 | 6.54±9.02 | <0.001 |
| Pastries and sweets | 44.45±49.83 | 26.83±30.13 | 33.57±43.17 | 14.02±13.73 | 9.40±18.48 | <0.001 |
| a: Obtained from ANOVA test. | ||||||
| Table 4. Components of demographics and severity of irritable bowel syndrome symptoms across quantiles of MIND diet. | ||||||
| Variables | Q1 | Q 2 | Q 3 | Q 4 | Q 5 | P-valuea |
| Age (year) | 30.35±9.99 | 33.72±12.63 | 31.61±11.05 | 31.70±10.49 | 30.08±9.52 | 0.01 |
| Body weight (kg) | 73.88±12.57 | 73.50±11.78 | 72.47±11.72 | 74.27±12.81 | 72.05±12.15 | 0.37 |
| Boy mass index(kg/m2) | 26.25±3.47 | 25.25±3.90 | 25.56±4.37 | 25.61±4.14 | 26.00±3.70 | 0.13 |
| Severity of symptoms | 32.92±8.45 | 27.62±9.96 | 29.38±7.35 | 28.59±8.78 | 31.22±9.06 | <0.001 |
| a: Obtained from ANOVA test. | ||||||
| Table 5. Odds ratio (95 % CI) for risk of depression and anxiety based on MIND diet in individuals with IBS. | ||||||
| Variables | IBS | Healthy | ||||
| OR | CI | P-valuea | OR | CI | P-valuea | |
| Depression Crude |
0.74 |
0.60 to 0.91 |
0.005 |
0.99 |
0.85 to 1.16 |
0.98 |
| Model 1 | 0.75 | 0.60 to 0.92 | 0.008 | 0.97 | 0.83 to 0.14 | 0.77 |
| Model 2 | 0.72 | 0.58 to 0.90 | 0.004 | 0.98 | 0.83 to 1.15 | 0.83 |
| Model 3 | 0.73 | 0.59 to 0.91 | 0.006 | 0.95 | 0.80 to 1.12 | 0.55 |
| Anxiety | ||||||
| Crude | 0.64 | 0.51 to 0.82 | <0.001 | 0.91 | 0.78 to 0.106 | 0.26 |
| Model 1 | 0.63 | 0.50 to 0.81 | <0.001 | 0.91 | 0.78 to 0.106 | 0.23 |
| Model 2 | 0.65 | 0.51 to 0.83 | 0.001 | 0.92 | 0.79 to 1.07 | 0.32 |
| Model 3 | 0.69 | 0.53 to 0.89 | 0.005 | 0.92 | 0.79 to 1.08 | 0.35 |
| a: Obtained from binary logistic regression; IBS: Irritable bowel syndrome, OR: Odds ratio; CI: Confidence interval; Model 1: adjusted for age and sex; Model 2:BMI and total energy intake; Model 3: additionally adjusted for educational status, and marital status. | ||||||
| Table 6. Odds ratio (95 % CI) for risk of severity of symptoms based on MIND diet. | ||||||
| IBS | Healthy | |||||
| Depression | OR | CI | P-valuea | OR | CI | P-valuea |
| Crude | 0.76 | 0.58 to 0.99 | 0.04 | 0.97 | 0.83 to 1.13 | 0.70 |
| Model 1 | 0.80 | 0.61 to 0.1.05 | 0.11 | 0.39 | 0.79 to 1.09 | 0.93 |
| Model 2 | 0.68 | 0.50 to 0.92 | 0.01 | 0.94 | 0.80 to 1.11 | 0.48 |
| Model 3 | 0.07 | 0.52 to 0.94 | 0.02 | 0.97 | 0.82 to 1.15 | 0.80 |
| a: Obtained from binary logistic regression; IBS: Irritable bowel syndrome, OR: Odds ratio; CI: Confidence interval; Model 1: adjusted for age and sex; Model 2:BMI and total energy intake; Model 3: additionally adjusted for educational status, and marital status. | ||||||
The gut-brain axis involves two-way communication between the central and enteric nervous systems, connecting the brain's emotional and cognitive centers with intestinal functions (Carabotti et al., 2015, Stasi et al., 2012). The hypothalamic-pituitary-adrenal (HPA) axis is key in regulating behavioral, neuroendocrine, and autonomic stress responses. Under stress, the autonomic nervous system triggers the release of corticotrophin-releasing factor (CRF) through the HPA axis, potentially disrupting gastrointestinal function (Dinan et al., 2006). Stress can elevate systemic proinflammatory cytokines, which can activate the HPA axis at the pituitary and send signals to the central nervous system through the vagus nerve (Kennedy et al., 2012). This can affect the GI tract, possibly due to the activation of eosinophils and mast cells in the intestinal lining, as observed in patients with IBS and FD (Walker et al., 2014) .
Diet can significantly influence the HPA axis, which plays a crucial role in stress response and overall health (Staudacher et al., 2024). Some studies have demonstrated that antioxidants can influence the HPA axis (Ge et al., 2016, Prevatto et al., 2017). For example, the results of experimental study indicate that resveratrol produces anxiety-reducing and antidepressant-like effects in rats with subclinical hypothyroidism by decreasing the overactivity of the HPA axis and modulating both the HPT axis and the Wnt/β-catenin pathway (Ge et al., 2016).
The MIND diet, similar to its component diets, highlights the importance of eating plant-based foods such as leafy green vegetables, nuts, berries, fish, and olive oil. It restricts the consumption of foods high in saturated fat and sugar, including red or processed meats, butter, margarine, full-fat cheese, pastries, sweets, and fried foods. (Barnes et al., 2023) The MIND diet is rich in omega-3 fatty acids, antioxidants, and various other nutrients that support brain health and cognitive function (Kamrani et al., 2024). A cross-sectional study investigated the relationship between HPA axis activity and fatty acid metabolism in adults diagnosed with recurrent depressive disorder (Thesing et al., 2018). The association between HPA-axis activity and fatty acid metabolism in adults with recurrent depressive disorder was studied. It was found that adults with low levels of omega-3 fatty acids exhibited a dysregulated HPA axis, indicating that treatment with these fatty acids could enhance both physical and mental health (Thesing et al., 2018). Results of clinical trials have shown that a 12-week supplementation with omega-3 fatty acids in adolescents with depression reduced morning salivary cortisol levels. However, this reduction was not seen in patients with mixed anxiety and depressive disorder but was notably significant in those with depressive disorder (Oravcova et al., 2022). Results of cross sectional study demonstrated that individuals with IBS, a high n-6/n-3 PUFA ratio was linked to increased depressive symptoms (Sanders et al., 2022).
IBS patients often experienced anxiety, which was linked to the severity of their symptoms (Cho et al., 2011). The study results indicate that adhering to the MIND diet can reduce the prevalence ratio of anxiety in patients with IBS. The previous studies were inconsistent with the results of the current study. The findings of a cross-sectional study showed no significant association between adherence to the MIND diet and the odds of anxiety (Salari-Moghaddam et al., 2019). Another study also reported no significant association between the MIND diet score and anxiety (Ardekani et al., 2023). However, the results of one study contradicted previous findings, showing a negative association between adherence to the MIND diet and both the odds and severity of anxiety (Torabynasab et al., 2023). Changes in gut microbiota are another way the MIND diet affects brain health. Inflammatory conditions may arise from changes in the composition of gut microbiota caused by consuming pro-inflammatory foods such as fats, sweets, and processed carbohydrates, rather than fiber, vegetables, and whole grains (Torabynasab et al., 2023).
To the best of the researchers' knowledge, this study is the first to examine the relationship between the MIND diet score and mental health in individuals with IBS. Additionally, dietary intake was evaluated using a validated FFQ, and potential confounders were accounted for using appropriate statistical methods. This study had some limitations. The cross-sectional design made it difficult to establish a causal link between the MIND diet and mental health. Additionally, the FFQ's reliance on participants' memory may have introduced measurement errors. Furthermore, wine was not included in the scoring process due to insufficient information in the FFQs.
Conclusion
This study showed that following the MIND diet can lower prevalence ratio of anxiety and depression in IBS patients. This diet is rich in components that promote brain health, including green leafy vegetables, other vegetables, nuts, berries, beans, whole grains, fish, poultry, olive oil, and wine. Further clinical trials are required to validate these findings.
Acknowledgments
The authors would like to thank the participants and co-researchers for their cooperation.
Authors' contributions
Abbasnezhad A designed the study; Fazeli Moghadam E, Abbasnezhad A and Samadi M conducted the study; Mohammadi M, Darabi Z, Fazeli Moghadam E, and Yarizadeh H wrote the manuscript and were involved in the analysis; Fazeli Moghadam E supervised the study. The final version of the manuscript was approved by all the authors.
Confilict of interests
The authors declared no competing interests.
Funding
Lorestan University of Medical Sciences supported this study.
References
Ardekani AM, et al. 2023. Evaluating the association between the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet, mental health, and cardio-metabolic risk factors among individuals with obesity. BMC endocrine disorders. 23 (1): 29.
Barnes LL, et al. 2023. Trial of the MIND diet for prevention of cognitive decline in older persons. New England Journal of Medicine. 389 (7): 602-611.
Bawadi H, et al. 2021. Validity and reproducibility of a food frequency questionnaire to assess macro and micro-nutrient intake among a convenience cohort of healthy adult Qataris. Nutrients. 13 (6): 2002.
Canavan C, West J & Card T 2014. The epidemiology of irritable bowel syndrome. Clinical epidemiology. 6: 71-80.
Carabotti M, Scirocco A, Maselli MA & Severi C 2015. The gut-brain axis: interactions between enteric microbiota, central and enteric nervous systems. Annals of gastroenterology: quarterly publication of the Hellenic Society of Gastroenterology. 28 (2): 203.
Chen EY, et al. 2024. The association between a Mediterranean diet and symptoms of irritable bowel syndrome. Clinical gastroenterology and hepatology. 22 (1): 164-172. e166.
Cho HS, et al. 2011. Anxiety, depression and quality of life in patients with irritable bowel syndrome. Gut and liver. 5 (1): 29.
de Lemos Zingano B, et al. 2019. Hospital Anxiety and Depression Scale-Anxiety subscale (HADS-A) and The State-Trait Anxiety Inventory (STAI) accuracy for anxiety disorders detection in drug-resistant mesial temporal lobe epilepsy patients. Journal of affective disorders. 246: 452-457.
Dinan TG, et al. 2006. Hypothalamic-pituitary-gut axis dysregulation in irritable bowel syndrome: plasma cytokines as a potential biomarker? Gastroenterology. 130 (2): 304-311.
Ge J-F, Xu Y-Y, Qin G, Cheng J-Q & Chen F-H 2016. Resveratrol ameliorates the anxiety-and depression-like behavior of subclinical hypothyroidism rat: possible involvement of the HPT axis, HPA axis, and Wnt/β-catenin pathway. Frontiers in endocrinology. 7: 44.
Gholamrezaei A, et al. 2011. Extra-intestinal Symptoms and their Relationship to Psychological Symptoms in Patients withIrritable Bowel Syndrome. Govaresh. 15 (2): 88-94.
Grajek M, et al. 2022. Nutrition and mental health: A review of current knowledge about the impact of diet on mental health. Frontiers in nutrition. 9: 943998.
Jahangiri P, et al. 2012. Irritable bowel syndrome in Iran: SEPAHAN systematic review No. 1. International journal of preventive medicine. 3 (Suppl1): S1.
Kamrani F, Kachouei AA, Sobhani SR & Khosravi M 2024. Nourishing the mind: how the EAT-Lancet reference diet (ELD) and MIND diet impact stress, anxiety, and depression. BMC psychiatry. 24 (1): 1-11.
Kennedy PJ, et al. 2012. Gut memories: towards a cognitive neurobiology of irritable bowel syndrome. Neuroscience & biobehavioral reviews. 36 (1): 310-340.
Kheirouri S & Alizadeh M 2022. MIND diet and cognitive performance in older adults: a systematic review. Critical reviews in food science and nutrition. 62 (29): 8059-8077.
Kroenke K, Spitzer RL & Williams JB 2001. The PHQ‐9: validity of a brief depression severity measure. Journal of general internal medicine. 16 (9): 606-613.
Lee C, et al. 2017. The increased level of depression and anxiety in irritable bowel syndrome patients compared with healthy controls: systematic review and meta-analysis. Journal of neurogastroenterology and motility. 23 (3): 349.
Mayer EA, Ryu HJ & Bhatt RR 2023. The neurobiology of irritable bowel syndrome. Molecular psychiatry. 28 (4): 1451-1465.
Midenfjord I, Polster A, Sjövall H, Törnblom H & Simrén M 2019. Anxiety and depression in irritable bowel syndrome: Exploring the interaction with other symptoms and pathophysiology using multivariate analyses. Neurogastroenterology & Motility. 31 (8): e13619.
Mohammadi S, et al. 2022. Evaluating the effects of dark chocolate formulated with micro‐encapsulated fermented garlic extract on cardio‐metabolic indices in hypertensive patients: A crossover, triple‐blind placebo‐controlled randomized clinical trial. Phytotherapy research. 36 (4): 1785-1796.
Oka P, et al. 2020. Global prevalence of irritable bowel syndrome according to Rome III or IV criteria: a systematic review and meta-analysis. lancet gastroenterology & hepatology. 5 (10): 908-917.
Oravcova H, et al. 2022. Stress hormones cortisol and aldosterone, and selected markers of oxidative stress in response to long-term supplementation with omega-3 fatty acids in adolescent children with depression. Antioxidants. 11 (8): 1546.
Prevatto JP, et al. 2017. Antioxidant treatment induces hyperactivation of the HPA axis by upregulating ACTH receptor in the adrenal and downregulating glucocorticoid receptors in the pituitary. Oxidative medicine and cellular longevity. 2017 (1): 4156361.
Ramstrand N, Ramstrand S, Brolund P, Norell K & Bergström P 2011. Relative effects of posture and activity on human height estimation from surveillance footage. Forensic science international. 212 (1-3): 27-31.
Salari-Moghaddam A, et al. 2019. Adherence to the MIND diet and prevalence of psychological disorders in adults. Journal of affective disorders. 256: 96-102.
Sanders AE, et al. 2022. Ratio of omega-6/omega-3 polyunsaturated fatty acids associated with somatic and depressive symptoms in people with painful temporomandibular disorder and irritable bowel syndrome. Journal of pain. 23 (10): 1737-1748.
Seifollahi A, et al. 2024. Associations between adherence to the MIND diet and prevalence of psychological disorders, and sleep disorders severity among obese and overweight women: a cross-sectional study. Nutrition and health. 30 (3): 513-519.
Shaikh SD, Sun N, Canakis A, Park WY & Weber HC 2023. Irritable bowel syndrome and the gut microbiome: a comprehensive review. Journal of clinical medicine. 12 (7): 2558.
Shiraseb F, et al. 2023. The association of dietary approaches to stop hypertension (DASH) and Mediterranean diet with mental health, sleep quality and chronotype in women with overweight and obesity: a cross-sectional study. Eating and weight disorders-studies on Anorexia, Bulimia and Obesity. 28 (1): 57.
Stasi C, Rosselli M, Bellini M, Laffi G & Milani S 2012. Altered neuro-endocrine–immune pathways in the irritable bowel syndrome: the top-down and the bottom-up model. Journal of gastroenterology. 47: 1177-1185.
Staudacher HM, Mikocka-Walus A & Ford AC 2021. Common mental disorders in irritable bowel syndrome: pathophysiology, management, and considerations for future randomised controlled trials. Lancet gastroenterology & hepatology. 6 (5): 401-410.
Staudacher HM, et al. 2024. Diet interventions for depression: Review and recommendations for practice. Australian & New Zealand Journal of Psychiatry. 59 (2): 115-127.
Tan J, Wang C & Tomiyama AJ 2024. Dietary Approaches to Stop Hypertension (DASH) diet and mental well-being: a systematic review. Nutrition reviews. 82 (1): 60-75.
Thesing CS, Bot M, Milaneschi Y, Giltay EJ & Penninx BW 2018. Omega-3 polyunsaturated fatty acid levels and dysregulations in biological stress systems. Psychoneuroendocrinology. 97: 206-215.
Torabynasab K, et al. 2023. Adherence to the MIND diet is inversely associated with odds and severity of anxiety disorders: a case–control study. BMC psychiatry. 23 (1): 330.
Ustaoğlu T, Tek NA & Yıldırım AE 2024. Evaluation of the effects of the FODMAP diet and probiotics on irritable bowel syndrome (IBS) symptoms, quality of life and depression in women with IBS. Journal of human nutrition and dietetics. 37 (1): 5-17.
Walker MM, et al. 2014. Duodenal eosinophilia and early satiety in functional dyspepsia: confirmation of a positive association in an A ustralian cohort. Journal of gastroenterology and hepatology. 29 (3): 474-479.
Zamani M, Alizadeh‐Tabari S & Zamani V 2019. Systematic review with meta‐analysis:
the prevalence of anxiety and depression in patients with irritable bowel syndrome. Alimentary pharmacology & therapeutics. 50 (2): 132-143.
Diet can significantly influence the HPA axis, which plays a crucial role in stress response and overall health (Staudacher et al., 2024). Some studies have demonstrated that antioxidants can influence the HPA axis (Ge et al., 2016, Prevatto et al., 2017). For example, the results of experimental study indicate that resveratrol produces anxiety-reducing and antidepressant-like effects in rats with subclinical hypothyroidism by decreasing the overactivity of the HPA axis and modulating both the HPT axis and the Wnt/β-catenin pathway (Ge et al., 2016).
The MIND diet, similar to its component diets, highlights the importance of eating plant-based foods such as leafy green vegetables, nuts, berries, fish, and olive oil. It restricts the consumption of foods high in saturated fat and sugar, including red or processed meats, butter, margarine, full-fat cheese, pastries, sweets, and fried foods. (Barnes et al., 2023) The MIND diet is rich in omega-3 fatty acids, antioxidants, and various other nutrients that support brain health and cognitive function (Kamrani et al., 2024). A cross-sectional study investigated the relationship between HPA axis activity and fatty acid metabolism in adults diagnosed with recurrent depressive disorder (Thesing et al., 2018). The association between HPA-axis activity and fatty acid metabolism in adults with recurrent depressive disorder was studied. It was found that adults with low levels of omega-3 fatty acids exhibited a dysregulated HPA axis, indicating that treatment with these fatty acids could enhance both physical and mental health (Thesing et al., 2018). Results of clinical trials have shown that a 12-week supplementation with omega-3 fatty acids in adolescents with depression reduced morning salivary cortisol levels. However, this reduction was not seen in patients with mixed anxiety and depressive disorder but was notably significant in those with depressive disorder (Oravcova et al., 2022). Results of cross sectional study demonstrated that individuals with IBS, a high n-6/n-3 PUFA ratio was linked to increased depressive symptoms (Sanders et al., 2022).
IBS patients often experienced anxiety, which was linked to the severity of their symptoms (Cho et al., 2011). The study results indicate that adhering to the MIND diet can reduce the prevalence ratio of anxiety in patients with IBS. The previous studies were inconsistent with the results of the current study. The findings of a cross-sectional study showed no significant association between adherence to the MIND diet and the odds of anxiety (Salari-Moghaddam et al., 2019). Another study also reported no significant association between the MIND diet score and anxiety (Ardekani et al., 2023). However, the results of one study contradicted previous findings, showing a negative association between adherence to the MIND diet and both the odds and severity of anxiety (Torabynasab et al., 2023). Changes in gut microbiota are another way the MIND diet affects brain health. Inflammatory conditions may arise from changes in the composition of gut microbiota caused by consuming pro-inflammatory foods such as fats, sweets, and processed carbohydrates, rather than fiber, vegetables, and whole grains (Torabynasab et al., 2023).
To the best of the researchers' knowledge, this study is the first to examine the relationship between the MIND diet score and mental health in individuals with IBS. Additionally, dietary intake was evaluated using a validated FFQ, and potential confounders were accounted for using appropriate statistical methods. This study had some limitations. The cross-sectional design made it difficult to establish a causal link between the MIND diet and mental health. Additionally, the FFQ's reliance on participants' memory may have introduced measurement errors. Furthermore, wine was not included in the scoring process due to insufficient information in the FFQs.
Conclusion
This study showed that following the MIND diet can lower prevalence ratio of anxiety and depression in IBS patients. This diet is rich in components that promote brain health, including green leafy vegetables, other vegetables, nuts, berries, beans, whole grains, fish, poultry, olive oil, and wine. Further clinical trials are required to validate these findings.
Acknowledgments
The authors would like to thank the participants and co-researchers for their cooperation.
Authors' contributions
Abbasnezhad A designed the study; Fazeli Moghadam E, Abbasnezhad A and Samadi M conducted the study; Mohammadi M, Darabi Z, Fazeli Moghadam E, and Yarizadeh H wrote the manuscript and were involved in the analysis; Fazeli Moghadam E supervised the study. The final version of the manuscript was approved by all the authors.
Confilict of interests
The authors declared no competing interests.
Funding
Lorestan University of Medical Sciences supported this study.
References
Ardekani AM, et al. 2023. Evaluating the association between the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet, mental health, and cardio-metabolic risk factors among individuals with obesity. BMC endocrine disorders. 23 (1): 29.
Barnes LL, et al. 2023. Trial of the MIND diet for prevention of cognitive decline in older persons. New England Journal of Medicine. 389 (7): 602-611.
Bawadi H, et al. 2021. Validity and reproducibility of a food frequency questionnaire to assess macro and micro-nutrient intake among a convenience cohort of healthy adult Qataris. Nutrients. 13 (6): 2002.
Canavan C, West J & Card T 2014. The epidemiology of irritable bowel syndrome. Clinical epidemiology. 6: 71-80.
Carabotti M, Scirocco A, Maselli MA & Severi C 2015. The gut-brain axis: interactions between enteric microbiota, central and enteric nervous systems. Annals of gastroenterology: quarterly publication of the Hellenic Society of Gastroenterology. 28 (2): 203.
Chen EY, et al. 2024. The association between a Mediterranean diet and symptoms of irritable bowel syndrome. Clinical gastroenterology and hepatology. 22 (1): 164-172. e166.
Cho HS, et al. 2011. Anxiety, depression and quality of life in patients with irritable bowel syndrome. Gut and liver. 5 (1): 29.
de Lemos Zingano B, et al. 2019. Hospital Anxiety and Depression Scale-Anxiety subscale (HADS-A) and The State-Trait Anxiety Inventory (STAI) accuracy for anxiety disorders detection in drug-resistant mesial temporal lobe epilepsy patients. Journal of affective disorders. 246: 452-457.
Dinan TG, et al. 2006. Hypothalamic-pituitary-gut axis dysregulation in irritable bowel syndrome: plasma cytokines as a potential biomarker? Gastroenterology. 130 (2): 304-311.
Ge J-F, Xu Y-Y, Qin G, Cheng J-Q & Chen F-H 2016. Resveratrol ameliorates the anxiety-and depression-like behavior of subclinical hypothyroidism rat: possible involvement of the HPT axis, HPA axis, and Wnt/β-catenin pathway. Frontiers in endocrinology. 7: 44.
Gholamrezaei A, et al. 2011. Extra-intestinal Symptoms and their Relationship to Psychological Symptoms in Patients withIrritable Bowel Syndrome. Govaresh. 15 (2): 88-94.
Grajek M, et al. 2022. Nutrition and mental health: A review of current knowledge about the impact of diet on mental health. Frontiers in nutrition. 9: 943998.
Jahangiri P, et al. 2012. Irritable bowel syndrome in Iran: SEPAHAN systematic review No. 1. International journal of preventive medicine. 3 (Suppl1): S1.
Kamrani F, Kachouei AA, Sobhani SR & Khosravi M 2024. Nourishing the mind: how the EAT-Lancet reference diet (ELD) and MIND diet impact stress, anxiety, and depression. BMC psychiatry. 24 (1): 1-11.
Kennedy PJ, et al. 2012. Gut memories: towards a cognitive neurobiology of irritable bowel syndrome. Neuroscience & biobehavioral reviews. 36 (1): 310-340.
Kheirouri S & Alizadeh M 2022. MIND diet and cognitive performance in older adults: a systematic review. Critical reviews in food science and nutrition. 62 (29): 8059-8077.
Kroenke K, Spitzer RL & Williams JB 2001. The PHQ‐9: validity of a brief depression severity measure. Journal of general internal medicine. 16 (9): 606-613.
Lee C, et al. 2017. The increased level of depression and anxiety in irritable bowel syndrome patients compared with healthy controls: systematic review and meta-analysis. Journal of neurogastroenterology and motility. 23 (3): 349.
Mayer EA, Ryu HJ & Bhatt RR 2023. The neurobiology of irritable bowel syndrome. Molecular psychiatry. 28 (4): 1451-1465.
Midenfjord I, Polster A, Sjövall H, Törnblom H & Simrén M 2019. Anxiety and depression in irritable bowel syndrome: Exploring the interaction with other symptoms and pathophysiology using multivariate analyses. Neurogastroenterology & Motility. 31 (8): e13619.
Mohammadi S, et al. 2022. Evaluating the effects of dark chocolate formulated with micro‐encapsulated fermented garlic extract on cardio‐metabolic indices in hypertensive patients: A crossover, triple‐blind placebo‐controlled randomized clinical trial. Phytotherapy research. 36 (4): 1785-1796.
Oka P, et al. 2020. Global prevalence of irritable bowel syndrome according to Rome III or IV criteria: a systematic review and meta-analysis. lancet gastroenterology & hepatology. 5 (10): 908-917.
Oravcova H, et al. 2022. Stress hormones cortisol and aldosterone, and selected markers of oxidative stress in response to long-term supplementation with omega-3 fatty acids in adolescent children with depression. Antioxidants. 11 (8): 1546.
Prevatto JP, et al. 2017. Antioxidant treatment induces hyperactivation of the HPA axis by upregulating ACTH receptor in the adrenal and downregulating glucocorticoid receptors in the pituitary. Oxidative medicine and cellular longevity. 2017 (1): 4156361.
Ramstrand N, Ramstrand S, Brolund P, Norell K & Bergström P 2011. Relative effects of posture and activity on human height estimation from surveillance footage. Forensic science international. 212 (1-3): 27-31.
Salari-Moghaddam A, et al. 2019. Adherence to the MIND diet and prevalence of psychological disorders in adults. Journal of affective disorders. 256: 96-102.
Sanders AE, et al. 2022. Ratio of omega-6/omega-3 polyunsaturated fatty acids associated with somatic and depressive symptoms in people with painful temporomandibular disorder and irritable bowel syndrome. Journal of pain. 23 (10): 1737-1748.
Seifollahi A, et al. 2024. Associations between adherence to the MIND diet and prevalence of psychological disorders, and sleep disorders severity among obese and overweight women: a cross-sectional study. Nutrition and health. 30 (3): 513-519.
Shaikh SD, Sun N, Canakis A, Park WY & Weber HC 2023. Irritable bowel syndrome and the gut microbiome: a comprehensive review. Journal of clinical medicine. 12 (7): 2558.
Shiraseb F, et al. 2023. The association of dietary approaches to stop hypertension (DASH) and Mediterranean diet with mental health, sleep quality and chronotype in women with overweight and obesity: a cross-sectional study. Eating and weight disorders-studies on Anorexia, Bulimia and Obesity. 28 (1): 57.
Stasi C, Rosselli M, Bellini M, Laffi G & Milani S 2012. Altered neuro-endocrine–immune pathways in the irritable bowel syndrome: the top-down and the bottom-up model. Journal of gastroenterology. 47: 1177-1185.
Staudacher HM, Mikocka-Walus A & Ford AC 2021. Common mental disorders in irritable bowel syndrome: pathophysiology, management, and considerations for future randomised controlled trials. Lancet gastroenterology & hepatology. 6 (5): 401-410.
Staudacher HM, et al. 2024. Diet interventions for depression: Review and recommendations for practice. Australian & New Zealand Journal of Psychiatry. 59 (2): 115-127.
Tan J, Wang C & Tomiyama AJ 2024. Dietary Approaches to Stop Hypertension (DASH) diet and mental well-being: a systematic review. Nutrition reviews. 82 (1): 60-75.
Thesing CS, Bot M, Milaneschi Y, Giltay EJ & Penninx BW 2018. Omega-3 polyunsaturated fatty acid levels and dysregulations in biological stress systems. Psychoneuroendocrinology. 97: 206-215.
Torabynasab K, et al. 2023. Adherence to the MIND diet is inversely associated with odds and severity of anxiety disorders: a case–control study. BMC psychiatry. 23 (1): 330.
Ustaoğlu T, Tek NA & Yıldırım AE 2024. Evaluation of the effects of the FODMAP diet and probiotics on irritable bowel syndrome (IBS) symptoms, quality of life and depression in women with IBS. Journal of human nutrition and dietetics. 37 (1): 5-17.
Walker MM, et al. 2014. Duodenal eosinophilia and early satiety in functional dyspepsia: confirmation of a positive association in an A ustralian cohort. Journal of gastroenterology and hepatology. 29 (3): 474-479.
Zamani M, Alizadeh‐Tabari S & Zamani V 2019. Systematic review with meta‐analysis:
the prevalence of anxiety and depression in patients with irritable bowel syndrome. Alimentary pharmacology & therapeutics. 50 (2): 132-143.
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