Association between breastfeeding and multiple sclerosis: A literature review

Early environmental exposures and lifestyle during childhood and adolescence have been proposed as possible risk factors for developing multiple sclerosis (MS). Additionally, some modifications in lifestyle, particularly in working mothers and some individuals, have been associated with a decrease in lactation and probably an increase in MS cases. The objective of this review was to perform a descriptive analysis of the possible relationship between breastfeeding and the development of MS. A literature search was conducted by the keywords breastfeeding, human milk, breast milk, mother milk, meta-analysis, risk factor, systematic review and multiple sclerosis on databases of Google scholar, PubMed, Research Gate, with a timeframe from 2021 to 2025 to identify research articles related to duration of breastfeeding and its possible association with MS. When global exclusive breastfeeding rates during the first six months of life, reported by the World Health Organization and the United Nations Children's Fund, were compared with worldwide MS prevalence, an ecological pattern emerges suggesting a possible inverse relationship between breastfeeding and MS risk, although this approach is prone to ecological fallacy and confusion. Most reports suggest that breastfeeding is inversely related to the occurrence of MS; this might reveal an association with MS risk. This possible influence of breastfeeding has been established after 4 months of breast milk feeding in early childhood and might indicate a high defense when lactation lasts from 6 to 12 months.