In 2017 several researchers published a review article in the journal, Alimentary Pharmacology and Therapeutics on breastfeeding and the risk of Crohn's disease and ulcerative colitis. They searched two online databases for all scientific studies conducted through November 2016 that described breastfeeding in infancy in patients with one of these illnesses. Then the authors conducted a meta-analysis of 35 of the best quality studies. These studies included a total of 7536 individuals with Crohns Disease and 7353 individuals with ulcerative colitis.
The study concluded that having been breastfed in infancy protects
against later development of both Crohn's disease and ulcerative
colitis. The results were true across all ethnic group, but protection was the greatest for the Asian community. Also, the results showed a dose-dependent relationship between breastfeeding and protection against the two diseases. A dose-dependent relationship means that breastfeeding longer instills greater protection than less months of breastfeeding. The strongest decrease in risk was seen when individuals were breastfed at least 12 months.
Abstract of the article