Fruits and vegetables intake may be associated with a reduced odds of multiple sclerosis: a systematic review and dose–response meta-analysis of observational studies

ABSTRACT

Introduction

Multiple sclerosis (MS) is an immune-mediated condition of the central nervous system (CNS). Intake of fruits and vegetables high in vitamins, minerals, fiber, and active molecules contributes to the body’s overall health, immunity, and physiological function. This study sought to review the literature and investigate the relationship between fruits and vegetables consumption and MS odds.

Methods

In the current systematic review and meta-analysis, a systematic search of original databases from inception to 21 Dec 2022 was conducted based on the PRISMA 2020 statement. Human observational studies examining the association between fruits or vegetables consumption and MS prevalence were included if they reported and provided effect size with 95% confidence intervals (CIs).

Results

The systematic review and meta-analysis included eight studies. Random effect model showed the protective effect of fruits (I² = 81.0%, P for heterogeneity < 0.001; pooled OR = 0.52, 95%CI = 0.27, 0.97, P-value = 0.042) and vegetables consumption (I² = 73.5%, P for heterogeneity = 0.002; pooled OR = 0.61, 95%CI = 0.38, 1.00, P-value = 0.050) on MS odds. According to a linear dose–response meta-analysis of four case–control studies, an increase of 100 grams of fruits per day reduced the odds of MS by 9% (I² = 0.0%, P for heterogeneity = 0.77; pooled OR = 0.91, 95%CI = 0.83, 0.99, P-value = 0.021).

Conclusion

Consumption of fruits and vegetables may be associated with a potential protective effect against MS. However, further confirmation is required through prospective longitudinal studies and randomized clinical trials.

KEYWORDS:

• Multiple sclerosis
• odds
• meta-analysis
• fruits
• vegetables
• systematic review
• dose-response
• diet

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.

Notes on contributors

Danial Fotros

Danial Fotros is a master's student in clinical nutrition and has specialized in the field of research on the relationship between nutrition and neurological disorders such as migraine headaches and multiple sclerosis.

Morvarid Noormohammadi

Morvarid Noormohammadi is currently pursuing a PhD in Nutrition Sciences and as a PhD candidate, her research is centered on understanding how diet affects inflammatory conditions and immune responses, particularly in relation to migraines and multiple sclerosis.

Soodeh Razeghi Jahromi

Dr. Soodeh Razeghi Jahromi, Ph.D, an Associate Professor in Nutrition Sciences, specializes in exploring the connection between nutrition and neurological disorders such as migraines and multiple sclerosis.

Mohammadjavad Abdolkarimi

Mohammadjavad Abdolkarimi is currently pursuing his Master's degree in Clinical Nutrition and is working on his Master's thesis.