Breastfeeding and Infant Growth Standards

Overview

The growth patterns of breastfed and formula-fed infants are different. For example:

• Healthy breastfed infants typically put on weight more slowly than formula-fed infants in their first year.12
• Formula-fed infants typically gain weight more quickly after about 3 months of age.
• Differences in weight patterns continue even after introducing complementary foods.1

Linear growth patterns of breastfed and formula-fed infants are similar.

WHO growth standards

The WHO child growth standards consider the effect of infant feeding on growth by using breastfeeding as the norm. In creating growth curves, WHO considered the differences in growth patterns of breastfed and formula-fed infants.3

In the WHO child growth charts:

• A healthy breastfed infant is the standard against which to compare all other infants.
• All infants in the WHO sample were breastfed at least until 12 months and predominantly breastfed for at least 4 months.
• Complementary foods were introduced at the mean age of 5.4 months.

The breastfed infant is the reference or normative model against which to measure alternative feeding methods for growth and healthy development.4 This is also true for other short-term and long-term outcomes.4

Using the breastfed infant as reference model is consistent with U.S. dietary reference intakes. For those, human milk composition and the average volume of human milk intake5 determine the norms for most infant nutrient intake.

CDC growth charts

CDC growth reference charts were developed to represent all U.S. infants. Feeding criteria were not identified.

The CDC growth charts are based on primarily formula-fed infants.

• Only about 50% of U.S. infants measured to create the CDC growth charts were ever breastfed.
• By age 3 months, only 33% of U.S. infants were being breastfed.

Currently, in the United States, most infants start to breastfeed.6 As a result, the CDC growth charts may not adequately reflect current U.S. infant growth patterns. The CDC growth charts also do not reflect the growth pattern typically seen in breastfed infants.

Breastfeeding and the growth standards

In 2006, CDC, the National Institutes of Health, and the American Academy of Pediatrics (AAP) convened an expert panel. The panelists reviewed the scientific evidence and discussed potentially using growth charts in U.S. clinical settings.

The panelists agreed that breastfeeding is the optimal form of infant feeding. They also agreed that using the WHO child growth standards for children from birth to 2 years helps support U.S. infant-feeding recommendations. This is because the WHO growth standards are based on breastfed infants.

The U.S. Dietary Guidelines for Americans recommend that infants be exclusively breastfed for about the first 6 months. Breastfeeding should continue while introducing appropriate complementary foods until the child is 12 months old or older.

The AAP and WHO also recommend that infants be exclusively breastfed for the first 6 months. They further recommend continued breastfeeding along with introducing appropriate complementary foods until the child is 2 years of age or older.

Test your knowledge

1. The growth patterns between breastfed and formula-fed infants differ. Which statement accurately describes these differences:
   1. Formula-fed Infants typically gain weight more slowly after 3 months of age compared to breastfed infants.
   2. Healthy, breastfed infants typically gain weight slower than formula-fed infants in the first year of life.
2. The CDC growth charts do not reflect a growth pattern typically seen in breastfed infants.
   1. True
   2. False

See answers.A