Is the "breast is best" mantra an oversimplification?
Recommendations about breastfeeding—absent critical analysis and removed from context—may overvalue its benefit. Here's a look at the evidence.
PRACTICE RECOMMENDATIONS
› Encourage breastfeeding for its potential to reduce the risk of acute otitis media, upper- and lower-respiratory infections, gastrointestinal infection, and dental malocclusion. A
› Promote breastfeeding for its potential to make a small difference in intelligence quotient and the incidence of overweight and obesity—but not for any other significant impact on long-term health. B
› Consider the needs and preferences of the individual when advocating breastfeeding so as to avoid potentially engendering maternal feelings of guilt and inadequacy. C
Strength of recommendation (SOR)
A Good-quality patient-oriented evidence
B Inconsistent or limited-quality patient-oriented evidence
C Consensus, usual practice, opinion, disease-oriented evidence, case series
From The Journal of Family Practice | 2018;67(6):E1-E9.
Infectious disease
Acute otitis media. Exclusive breastfeeding for 6 months is associated with a 43% reduction in the risk of acute otitis media (AOM) by 2 years of age (odds ratio [OR]=0.57; 95% confidence interval [CI], 0.44-0.75). Beyond 2 years of age, or when comparing “ever” and “never” breastfeeding, the effect disappears. All studies in this meta-analysis had serious limitations.18
Nearly half of children will have at least one case of AOM by one year of age; 80%, by 2 years.19,20 Since the introduction of the heptavalent pneumococcal conjugate vaccine, the rate of AOM at 2 years has fallen by as much as 20%.21 Assuming an incidence of 60% to 80% of AOM by 2 years, only 2 or 3 infants need to be exclusively breastfed for 6 months to prevent a single case of AOM.18 Prevention of AOM through breastfeeding may be related to head position during feeding, antibacterial effects of breast milk, protective oral microbiome in the breastfed infant pharynx, and/or prevention of primary viral upper respiratory infection (URI), which nearly always precedes AOM.18,19
Upper and lower respiratory tract infections. Infants who are exclusively breastfed for 4 months and partially breastfed after 4 months have a lower risk of URI (OR=0.65; 95% CI, 0.51-0.83) and of lower respiratory tract infection (LRTI; OR=0.50; 95% CI, 0.32-0.72).22
The effect is stronger for URI among infants exclusively breastfed for at least 6 months (OR=0.37; 95% CI, 0.18-0.74), but is no longer significant by that time for LRTI (OR=0.33; 95% CI, 0.08-1.40). Importantly, AOM was included in the URI group, and, as previously discussed, AOM has independently been shown to have an inverse relationship with breastfeeding duration.
At 7 to 12 months of age, no association was seen between breastfeeding and the incidence of URI. Curiously, an association with LRTI was again detected for infants breastfed exclusively for 4 months and partially thereafter, but was not detected with exclusive breastfeeding for at least 6 months (OR=0.46; 95% CI, 0.31-0.69). In this study, in the first 6 months of life, 40% of infants had a URI and 8% had an LRTI. The findings in this cohort suggest an NNT of 6 or 7 for prevention of URI and an NNT of 25 for prevention of LRTI in the first 6 months of life.22
Continue to: Children younger than 2 years are...
