Breastfeeding Reduces Risk of Respiratory Illness in Infants

Abstract

Breastfeeding has long been believed to protect against infection in infants, but protection against respiratory illnesses has not been consistently demonstrated in studies in developed countries. Between 1988 and 1992, the authors assessed the effect of breastfeeding on incidence and duration of respiratory illnesses during the first 6 months of life in a prospective study that actively tracked breastfeeding and respiratory illnesses. A cohort of 1,202 healthy infants, born in Albuquerque, New Mexico, between January 1, 1988 and June 30, 1990, from homes without smokers was enrolled. The daily occurrences of respiratory symptoms and breastfeeding status were reported by the mothers every 2 weeks. Illnesses were classified as lower respiratory illness (LRI) if wheezing or wet cough was reported; the remaining illnesses were classified as upper respiratory. The annualized incidence rates for LRI were 2.8, 2.6, and 2.1 during follow-up time with no, partial, or full breastfeeding, respectively, but the incidence rates for upper respiratory illness and lower respiratory illness combined were similar in the three categories. After adjustment for potential confounding factors, full breastfeeding was associated with a reduction in lower respiratory illness risk (odds ratio=0.81, 95% confidence interval 0.68-0.96). Median duration of all respiratory illnesses was 5 days for the fully breastfed infants during the first 6 months of life compared with a median of 6 days for not breastfed and partially breastfed infants. Multivariate analysis confirmed that breastfeeding significantly reduced the duration of respiratory illness. This pattern of reduced incidence of LRI and shorter duration of all respiratory illnesses suggests that breastfeeding reduces the severity of infant respiratory illnesses during the first 6 months of life.

Fatores associados à duração mediana do aleitamento materno em lactentes nascidos em município do estado de São Paulo

“…Nas últimas décadas, principalmente nos países em desenvolvimento, a valorização desta prática foi retomada propiciando a diminuição da desnutrição, dos processos alérgicos, da diarréia e da anemia [3][4][5][6] .…”

Prolonged and Exclusive Breastfeeding Reduces the Risk of Infectious Diseases in Infancy

“…[3][4][5][6][7][8] The risks of these infectious diseases are affected by several factors including birth weight, gestational age, socioeconomic status, ethnicity, number of siblings, day care attendance, and parental smoking. 3,5,6,[8][9][10][11][12][13][14][15][16][17][18][19][20] Breastfeeding has been suggested as a modifiable influencing factor. When given exclusively, breastfeeding reduces the risk of infectious diseases in infants in developing countries.…”

Changes in immunomodulatory constituents of human milk in response to active infection in the nursing infant

“…The immune system in human milk includes secretory immunoglobulin A (sIgA), immunoglobulin G, free fatty acids, monoglycerides, proteins such as lactoferrin, lactalbumin, glycans, nonabsorbed oligosaccharides, exosomes, immunomodulators such as cytokines, nucleic acids, antioxidants, and immune cells such as macrophages, neutrophils, and lymphocytes (1,4,5,(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17). All these immunologic milk constituents interact together and with the newborn's gut directly or indirectly (e.g., by changing the gut flora) to increase immunity against infection, and probably also contribute to the maturation and efficiency of the newborn immune system (5,6).Many studies in both industrialized and developing countries have shown that nursing infants are less vulnerable to infections during their first months of life, including gastroenteritis, respiratory infections, otitis media, urinary tract infections, and necrotizing enterocolitis in premature infants (3,(18)(19)(20)(21)(22)(23)(24)(25).The mechanisms involved in the immunity provided by human milk to the nursing infant are not fully understood. Until recently, it was believed that the changes in immunological constituents of breast milk were mostly related to the time that elapsed from delivery or, in some cases, were also related to the mother's nutritional state.…”

“…Many studies in both industrialized and developing countries have shown that nursing infants are less vulnerable to infections during their first months of life, including gastroenteritis, respiratory infections, otitis media, urinary tract infections, and necrotizing enterocolitis in premature infants (3,(18)(19)(20)(21)(22)(23)(24)(25).…”