As early as 1921, a report concerning the potential adverse effects of bottle-feeding infants appeared in a medical journal. At that time, medical professionals received significantly more education concerning artificial feeding in comparison with breastfeeding.1
Currently, the American Academy of Pediatrics recommends breastfeeding as the optimal source of nutrition through the first year of life: “We recommend exclusively breastfeeding for about the first six months of a baby’s life, and then gradually adding solid foods while continuing breastfeeding until at least the baby’s first birthday.”2
“Breast is Best” Health Benefits of Breastfeeding for Babies
- Bonding with mother
Skin-to-skin contact is important and breastfeeding helps provide an opportunity for bonding.
- Brain support
A study reported in the European Journal of Nutrition found better cognitive performance and gross motor skills among infants that were bottle-fed breast milk in comparison with those who were bottle-fed formula. Among infants who received only breast milk, those who were fed directly at the breast had better scores on some memory tasks compared to infants who were fed partially or completely by bottle.3
- Improved response to pain
A study that involved 100 one-day-old infants who were vaccinated for hepatitis B resulted in shorter crying duration during and after the injection among those who were breastfed compared to those who received powdered formula. The authors noted that human milk contains endorphins that are natural pain relievers.4
- Lower risk of obesity
Breast milk provides bioactive factors that may support a decreased risk of childhood obesity.5 In one study that collected anthropometric data from 203 infants during the first year of their lives, 4% of breastfed infants were overweight at 12 months of age compared with 7.6% of those who received both breast milk and formula.6
- Improved microbiome composition
Components of breast milk affect microbial colonization of an infant’s mucosa, which influences immune system development.7 Compared with the gut microbiota composition of breastfed infants, the gut microbiota composition of formula-fed infants has been found to more closely resemble the microbiota composition of adults who consume a Western diet.8
- Immune system support
Breast milk “provides protection during the newborn’s adaption to the extrauterine environment and reduces the morbidity and mortality caused by both infectious and noninfectious diseases,” note the authors of a Nestle Nutrition Institute Workshop series published in 2020. “Its components act directly against infectious agents, but they also accelerate the newborn’s immune system development, increasing its capacity for defense and reducing the risk of allergy and other immune-related diseases. Cytokines show the most refined immunomodulatory effects, but oligosaccharides, hormones and other components affect the newborn’s immunity as well.”7
Breastfed infants had a lower incidence of diarrheal illness and middle ear infections during the first year of life and shorter duration of middle ear infections during the second year of life compared with formula-fed infants in one study.9 Diabetes incidence was found to be lower later in life in an at-risk population group who were breastfed during their first two months of life.10
When Breastfeeding Alone is Not Enough
- Inadequate supply
Some women do not produce a healthy supply of milk. It then becomes necessary to supplement breast milk with donated breast milk or formula to provide the infant with enough nourishment. Breast milk has many components, including casein and whey protein, fatty acids and vitamins and minerals that infant formula manufacturers attempt to duplicate.11
- Insufficient amount of vitamin D
The nutrients that breastmilk is deficient in are vitamin K, iron and vitamin D.12 Infants who are deficient in vitamin D run the risk of poor bone mineralization and rickets. Women who breastfeed may need to supplement with at least 2000 international units (IU) vitamin D per day for their milk to provide an infant with enough of the vitamin to result in adequate levels.
Related Article: Prenatal Supplement for Mom: Before, During and After Pregnancy
According to the Institute of Medicine, people are at risk of vitamin D deficiency at a serum vitamin D level of less than 12 ng/mL and of inadequacy at 12-20 ng/mL.13 Babies who are exclusively breastfed by vitamin D-supplemented mothers may sometimes still fail to attain optimal levels. Writing in the journal Pediatrics, Carol L. Wagner, MD, Frank R. Greer, MD and the Section on Breastfeeding and Committee on Nutrition of the American Academy of Pediatrics recommends that “at this time it is prudent to recommend that all breastfed infants be given supplemental vitamin D3.”14
“A supplement of 400 IU/day of vitamin D should begin within the first few days of life and continue throughout childhood,” they continue. “Any breastfeeding infant, regardless of whether he or she is being supplemented with formula, should be supplemented with 400 IU of vitamin D, because it is unlikely that a breastfed infant would consume one liter of formula per day, the amount that would supply 400 IU of vitamin D.”
“Infants who are exclusively breastfed but who do not receive supplemental vitamin D or adequate sunlight exposure are at increased risk of developing vitamin D deficiency and/or rickets,” noted the author of a commentary in the Indian Journal of Medical Research. “The only practical option available is to seriously consider a routine vitamin D supplementation program starting from neonatal period extending right through the childhood into adolescence. In a recently published study, oral vitamin D3 supplementation as an oil emulsion has been shown to be associated with significant and sustained increases in 25(OH)D from baseline in fully breastfeeding infants through seven months.”15
In a study involving 2,244 infants, median time to first respiratory tract infection was longer than six months for those supplemented from birth with 400 to 600 IU vitamin D, in contrast with unsupplemented infants who experienced their first respiratory tract infection an average of 60 days after birth.16 Children who received vitamin D supplements five to seven days per week had a 54% lower risk of respiratory tract infection, an 83% lower risk of lower respiratory tract infection and an 82% lower risk of hospitalization related to respiratory tract infection in comparison with infants who did not receive the vitamin.
- Deficient vitamin K levels
An infant’s need for vitamin K, which is present only in low levels in breast milk, has led to the routine administration of injectable vitamin K to all newborns to prevent the risk of severe bleeding, which is 81 times more likely among those who do not receive vitamin K and can happen as long as six months after birth. Bleeding can occur anywhere, including in the brain, and is associated with mortality among 20% of all infants in whom it occurs.17
- Insufficient iron
Breast milk contains only a small amount of iron. Because most infants are born with iron already stored in their bodies, it is usually not necessary for those who are exclusively breastfed to begin receiving iron supplements until they are four months old. The recommended dose of supplemental iron for an infant is 1 milligram iron per kilogram (2.2 pounds) of the child’s body weight.18
A study that compared breast to bottle-fed babies found an absence of storage iron among 27.8% of those who were breastfed in contrast with none who received formula. Anemia incidence was four times higher in the breast-fed group compared to the formula group.19
The Bottom Line
Is breast best? The answer, in most cases, is a resounding yes, as long as infants receive key nutrients that are important for those of any age. The use of nutritional supplements (with a pediatrician’s approval) and timely introduction of solid food will help make up for insufficiencies associated with breast milk consumption.
About the author: Dayna Dye has been a member of the staff of Life Extension® since shortly after its inception. She has served as the department head of Life Extension® Wellness Specialists, is the author of thousands of articles published during the past two decades in Life Extension® Update, Life Extension Magazine® and on www.LifeExtension.com, and has been interviewed on radio and TV and in newsprint. She is currently a member of Life Extension’s Education Department.
- Sedgwick JP et al. Am J Public Health (N Y). 1921 Feb;11(2):153-7.
- “Where We Stand: Breastfeeding.” healthychildren.org The American Academy of Pediatrics. Updated 2014 11 July. www.healthychildren.org/English/ages-stages/baby/breastfeeding/Pages/Where-We-Stand-Breastfeeding.aspx
- Pang WW et al. Eur J Nutr. 2020 Mar;59(2):609-619.
- Hatami Bavarsad Z et al. Arch Pediatr. 2018 Aug;25(6):365-370.
- Marseglia L et al. Women Birth. 2015 Jun;28(2):81-6.
- Mandić Z et al. Matern Child Nutr. 2011 Oct;7(4):389-96.
- Tlaskalová-Hogenová H et al. Nestle Nutr Inst Workshop Ser. 2020 Mar 16;94:38-47.
- Siddharth J et al. PLoS One. 2013 Dec 31;8(12):e83689.
- Dewey KG et al. J Pediatr. 1995 May;126(5 Pt 1):696-702.
- Pettitt DG et al. Lancet. 1997 Jul 19;350(9072):166-8.
- Martin CR et al. Nutrients. 2016 May 11;8(5).
- “Breastfeeding and Special Circumstances.” Centers for Disease Control and Prevention. U.S. Department of Health & Human Services. Last reviewed 2019 22 Dec. www.cdc.gov/breastfeeding/breastfeeding-special-circumstances/index.html
- “Vitamin D Fact Sheet for Health Professionals.” National Institutes of Health Office of Dietary Supplements. National Institutes of Health. U.S. Department of Health & Human Services. Updated 2020 24 March. www.ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/
- Wagner CL et al. Pediatrics. 2008 Nov;122(5):1142-52.
- Balsubramanian S. Indian J Med Res. 2011 Mar;133:250-2.
- Hong M et al. Matern Child Nutr. 2020 Mar 5:e12987.
- “FAQs.” Vitamin K Deficiency Bleeding. Centers for Disease Control and Prevention. Reviewed 2019 19 Feb. www.cdc.gov/ncbddd/vitamink/faqs.html
- “Iron.” Breastfeeding. Centers for Disease Control and Prevention. Reviewed 2019 14 Feb. www.cdc.gov/breastfeeding/breastfeeding-special-circumstances/diet-and-micronutrients/iron.html
- Calvo EB et al. Pediatrics. 1992 Sep;90(3):375-9.