Association between multiple sclerosis and dietary patterns based on the traditional concept of food nature: a case-control study in Iran

A systematic review and meta-analysis of Dietary Inflammatory Index and the likelihood of multiple sclerosis/ demyelinating autoimmune disease

Diet and inflammation may contribute to the development of multiple sclerosis (MS). The aim of this systematic review and meta-analysis was to assess the association between proinflammatory diet, as estimated by the Dietary Inflammatory Index (DII®), and the likelihood of developing MS or other demyelinating autoimmune diseases. A systematic search was performed of search engines and databases (PubMed, ISI Web of Sciences, Scopus, and Embase) to identify relevant studies before 10th June 2023. The search identified 182 potential studies, from which 39 full-text articles were screened for relevance. Five articles with case-control design (n = 4,322, intervention group: 1714; control group: 2608) met the study inclusion criteria. The exposure variable was DII, with studies using two distinct models: quartile-based comparisons of DII and assessment of continuous DII. The meta-analysis of high versus low quartiles of DII with four effect sizes showed a significant association with MS/demyelinating autoimmune disease likelihood, with an odds ratio (OR) of 3.26 (95% confidence interval (CI) 1.16, 9.10). The meta-analysis of four studies with DII fit as a continuous variable showed a 31% increased likelihood of MS per unit increment; which was not statistically significant at the nominal alpha equals 0.05 (OR 1.31; 95% CI 0.95, 1.81). In conclusion, this systematic review and meta-analysis provides evidence of a positive association between higher DII scores with the likelihood of developing MS, highlighting that diet-induced inflammation could play a role in MS or other demyelinating autoimmune diseases risk.

The Role of Diet in Multiple Sclerosis Onset: A Prospective Study Using UK Biobank

Multiple sclerosis (MS) is a debilitating autoimmune condition primarily affecting young adults, and its rise is evident globally. Despite this, its precise etiology remains elusive. Both genetic and environmental factors contribute to MS susceptibility; however, the link between diet and MS lacks substantial evidence due to limited large-scale studies. We exploited the UK Biobank resources to explore the nexus between diet, lifestyle, and MS risk. The dietary and lifestyle habits of MS incident cases, derived from a general food frequency questionnaire (FFQ) completed by all participants at study enrollment, were compared to those of subjects who did not develop MS during the follow-up. Our findings suggest the protective role of moderate oily fish consumption and weekly alcohol intake. Furthermore, by analyzing food intake data obtained through 24 h recall, completed by a subset of participants, we found a protective, though non-significant, trend of an increased adherence to the Mediterranean diet (MD). These findings, derived from the analysis of the UK Biobank and representing an unprecedented approach for this inquiry, warrant further exploration and integration in future research.

Effects of Dietary Modification Based on Complementary and Alternative Iranian Medicine in Patients with Secondary-Progressive Multiple Sclerosis: A Randomized Controlled Clinical Trial

Objectives: To evaluate the efficacy of dietary modifications based on complementary and alternative Iranian medicine (CAIM) in patients with secondary-progressive multiple sclerosis (SPMS). Design: In this randomized controlled trial, 70 SPMS patients were randomized to receive either a moderate-nature diet based on Persian medicine (as intervention) or usual diet plus health-related diet recommendations (as control) for 2 months. Serum high-sensitivity C-reactive protein (hs-CRP), erythrocyte sedimentation rate (ESR), Expanded Disability Status Scale (EDSS), Modified Fatigue Impact Scale (MFIS), State-Trait Anxiety Inventory (STAI), Global Pain Scale (GPS), Gastrointestinal Symptom Rating Scale (GSRS), anthropometric measurements, and quality of life (QOL) were assessed at baseline and end of trial. Analysis of covariance was performed, and the results were adjusted for potential confounders using SPSS v.14. Results: All participants completed the study for 2 months. There were significant improvements across the mean changes of hs-CRP (-0.1 ± 0.2 mg/L for intervention vs. -0.01 ± 0.13 mg/L for control; padjusted = 0.012), MFIS (-11.0 ± 11.8 vs. -0.7 ± 9.9; padjusted <0.001), GSRS (-19.9 ± 16.3 to 1.2 ± 17.5; padjusted <0.001), GPS (padjusted = 0.032), and QOL (padjusted <0.05). No significant difference was observed across the ESR, EDSS, STAI, and anthropometric measurements. Conclusion: Dietary modifications based on CAIM may improve inflammation and clinical manifestations in SPMS patients. Nonetheless, further trials are required to confirm these findings. Clinical Trial Registration: IRCT20181113041641N2.

Longitudinal associations between quality of diet and disability over 7.5 years in an international sample of people with multiple sclerosis

BACKGROUND AND PURPOSE

Modifiable lifestyle factors, including diet, have been implicated in multiple sclerosis (MS) progression, but prospective evidence is limited. The aim of this study was to examine prospective relationships between quality of diet and subsequent disability over 7.5 years in an international cohort of people living with MS (pwMS).

METHODS

Data from 602 participants in the HOLISM (Health Outcomes and Lifestyle In a Sample of people with Multiple sclerosis) study were analysed. Quality of diet was assessed using the modified Diet Habits Questionnaire (DHQ). Disability was assessed using the Patient-determined MS Severity Score (P-MSSS). Characteristics of disability were assessed by log-binomial, log-multinomial and linear regression, adjusted for demographic and clinical covariates, as appropriate.

RESULTS

Higher baseline total DHQ scores (>80-89, >89%) were associated with lower risks of increased P-MSSS at 7.5 years (adjusted risk ratio [aRR] 0.46, 95% confidence interval [CI] 0.23, 0.91 and aRR 0.48, 95% CI 0.26, 0.89, respectively), and with less P-MSSS accrual (aβ = -0.38, 95% CI -0.78, 0.01 and aβ = -0.44, 95% CI -0.81, -0.06). Of the DHQ domains, fat subscore was most strongly associated with subsequent disability. Participants with reducing baseline-to-2.5- years total DHQ scores had greater risk of increased P-MSSS at 7.5 years (aRR 2.77, 95% CI 1.18, 6.53) and higher P-MSSS accrual (aβ = 0.30, 95% CI 0.01, 0.60). Participants reporting baseline meat and dairy consumption had greater risk of increased P-MSSS at 7.5 years (aRR 2.06, 95% CI 1.23, 3.45 and aRR 2.02, 95% CI 1.25, 3.25) and higher P-MSSS accrual (aβ = 0.28, 95% CI 0.02, 0.54 and aβ = 0.43, 95% CI 0.16, 0.69, respectively). However, reported meat consumption was confounded by quality of diet. Changes in meat or dairy consumption from baseline were inconsistently associated with subsequent disability.

CONCLUSIONS

We show for the first time robust long-term associations between quality of diet and subsequent disability progression in pwMS. Subject to replication, dietary modification may represent a point of intervention for reducing disability in pwMS.

Inverse association between Mediterranean diet and risk of multiple sclerosis

OBJECTIVE

There is some evidence implicating diet in the development of inflammatory diseases. We aimed to study the influence of dietary habits on the risk of developing multiple sclerosis (MS).

METHODS

We used a population-based case-control study recruiting incident cases of MS (1953 cases, 3557 controls). Subjects with different dietary habits 5 years prior to MS diagnosis were compared regarding MS risk by calculating odds ratios (OR) with 95% confidence intervals (CI) using logistic regression models. Adjustment was made for a large number of environmental and lifestyle habits, including ancestry, smoking, alcohol consumption, body mass index, physical activity, and sun exposure habits.

RESULTS

Mediterranean diet was associated with lower risk of developing MS (adjusted OR = 0.54, 95% CI: 0.34-0.86, p = 0.009), compared with Western-style diet. There was no significant association between vegetarian/vegan diet and MS risk (adjusted OR = 0.96, 95% CI: 0.75-1.24, p = 0.976), nor between diet with low glycemic index and MS risk (adjusted OR = 0.93, 95% CI: 0.60-1.42, p = 0.518).

CONCLUSIONS

Mediterranean diet may exert a protective influence regarding the risk of subsequently developing MS compared with Western-style diet.

Dietary patterns and the risk of Alzheimer's disease in an elderly Iranian population: a case-control study

BACKGROUND

An increasing number of studies in Western countries have shown that healthy eating patterns have a protective effect against cognitive decline and dementia, however, information about this relationship among non-western populations with different cultural environments is scarce. The present study investigated the association between dietary patterns (DPs) and cognitive function in the Iranian elderly.

METHODS

In this case-control study, the data of 290 elderly people in two groups of case and control (Mean age in case: 74.2 ± 8.6, in control: 67.3 ± 7.3 year) were analyzed. Two DPs of healthy and unhealthy were extracted from a 142-item dish-based food frequency questionnaire, and patterns driven by principal components analysis (PCA) of 25 food groups. Multivariate binary logistic regression calculated the odds ratio (OR) of cognitive impairment with adjustment for potential confounding factors.

RESULTS

A healthy DP, characterized by high consumption of fruits and vegetables, legumes, and nuts, was related to a decrease in the odds of Alzheimer's disease in Iranian elderly people. Also, moderate adherence to an unhealthy food pattern was associated with an increase in the probability of the disease; however, the association was not statistically significant.

CONCLUSION

In this elderly population, a healthy eating pattern was associated with reducing the risk of Alzheimer's disease. Further prospective studies are recommended.

Involvement of the Intestinal Microbiota in the Appearance of Multiple Sclerosis: Aloe vera and Citrus bergamia as Potential Candidates for Intestinal Health

Multiple sclerosis (MS) is a neurological and inflammatory autoimmune disease of the Central Nervous System in which selective activation of T and B lymphocytes prompts a reaction against myelin, inducing demyelination and axonal loss. Although MS is recognized to be an autoimmune pathology, the specific causes are many; thus, to date, it has been considered a disorder resulting from environmental factors in genetically susceptible individuals. Among the environmental factors hypothetically involved in MS, nutrition seems to be well related, although the role of nutritional factors is still unclear. The gut of mammals is home to a bacterial community of about 2000 species known as the “microbiota”, whose composition changes throughout the life of each individual. There are five bacterial phylas that make up the microbiota in healthy adults: Firmicutes (79.4%), Bacteroidetes (16.9%), Actinobacteria (2.5%), Proteobacteria (1%) and Verrucomicrobia (0.1%). The diversity and abundance of microbial populations justifies a condition known as eubiosis. On the contrary, the state of dysbiosis refers to altered diversity and abundance of the microbiota. Many studies carried out in the last few years have demonstrated that there is a relationship between the intestinal microflora and the progression of multiple sclerosis. This correlation was also demonstrated by the discovery that patients with MS, treated with specific prebiotics and probiotics, have greatly increased bacterial diversity in the intestinal microbiota, which might be otherwise reduced or absent. In particular, natural extracts of Aloe vera and bergamot fruits, rich in polyphenols and with a high percentage of polysaccharides (mostly found in indigestible and fermentable fibers), appear to be potential candidates to re-equilibrate the gut microbiota in MS patients. The present review article aims to assess the pathophysiological mechanisms that reveal the role of the microbiota in the development of MS. In addition, the potential for supplementing patients undergoing early stages of MS with Aloe vera as well as bergamot fibers, on top of conventional drug treatments, is discussed.