According to a new French study in people with a family history of ankylosing spondylitis who carry the HLA-B27 gene, breastfeeding may provide a layer of protection against developing AS later in life. The protective agent seems to be the microbiota that is induced in the infant’s gastrointestinal tract by breastfeeding, which differs from microbiota induced by formula.
The researchers note that, “Microbiota acquisition begins at birth and continues throughout the first months of life. Microbes from the mother and the environment colonize the newborn’s skin and gastrointestinal tract. Maternal milk contains up to 109 microbes per liter, and is the first source of microbes to colonize the gastrointestinal tract.”
“The breastfeeding data in the new study is based on data collected from 119 families with ankylosing spondylitis. It includes 203 patients who were positive for HLA-B27 and a control group of 293 healthy siblings.”
Study Results: “Patients with AS had been breast fed less often than healthy controls. In families where children were breast fed, the patients with AS were less often breast fed than their healthy siblings (57% vs 72%), giving an OR for AS onset of 0.53 (95% CI (0.36 to 0.77), p value=0.0009). Breast feeding reduced familial prevalence of AS. The frequency of breast feeding was similar in the AS siblings and in the 280 unrelated controls. However, patients with AS were less often breast fed compared with the 280 unrelated controls (OR 0.6, 95% CI (0.42 to 0.89), p<0.01).”
The researchers concluded that “breastfeeding has the potential to provide a protective effect on the development of ankylosing spondylitis, but additional studies are needed to determine if this degree of protection can lead to an understanding of the mechanism of the observed protection.”
Further reading and sources used:
Spondylitis Association of America