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Work Under Way

Question

What is the relationship between the duration of exclusive human milk and/or infant formula consumption and long-term health outcomes?

Approach to Answering the Question
Existing NESR Systematic Review

Subcommittee
Birth to 24 Months Subcommittee

Systematic Review Protocol
Developed for each scientific question being examined, the protocol describes the plan for how the systematic review will be conducted.

For this question, the existing NESR systematic reviews were conducted during the Pregnancy and Birth to 24 Months Project, and captured evidence published from January 1980 to March 2016. The Infant Milk-Feeding Practices Technical Expert Collaborative conducted the systematic reviews in collaboration with staff from USDA’s Nutrition Evidence Systematic Review (NESR). Complete documentation of the existing systematic reviews and the related publication in the American Journal of Clinical Nutrition is available on the NESR website:

For additional details, see the full protocol for the question, what is the relationship between the duration of exclusive human milk and/or infant formula consumption and long-term health outcomes? 

View Full Protocol

Draft Conclusion Statement

The draft conclusion statements listed below describe the state of the science related to the specific question examined. Draft conclusions are not considered final until they have been deliberated with and decided upon by the full Committee and published in the Committee’s final advisory report. Individual conclusion statements should not be interpreted as dietary guidance or the Committee’s overarching advice to the Departments.

Diabetes

Ever vs Never Consuming Human Milk

Limited evidence from observational studies suggests that never versus ever being fed human milk is associated with higher risk of type 1 diabetes. Grade: Limited 

There is insufficient evidence to determine whether or not there is a relationship between never versus ever feeding human milk and type 2 diabetes, prediabetes, fasting glucose, HbA1c, insulin resistance, and glucose tolerance throughout the lifespan. Grade: Grade Not Assignable 

Duration of Any Human Milk Consumption Among Infants Fed Human Milk

Moderate evidence from observational studies suggests that, among infants fed some amount of human milk, shorter versus longer durations of any human milk feeding are associated with higher risk of type 1 diabetes. Grade: Moderate

Limited but consistent evidence suggests that the duration of any human milk feeding is not associated with fasting glucose or insulin resistance in childhood or during the transition from childhood into adolescence. Grade: Limited

There is insufficient evidence to determine whether or not there is a relationship between shorter versus longer durations of any human milk feeding and type 2 diabetes, prediabetes, or HbA1C throughout the lifespan, and fasting glucose and insulin resistance in adulthood. Grade: Grade Not Assignable 

Duration of Exclusive Human Milk Consumption

Limited evidence from observational studies suggests that shorter versus longer durations of exclusive human milk feeding are associated with higher risk of type 1 diabetes. Grade: Limited

Limited evidence, from a single study that used a strong design, also suggests that the duration of exclusive human milk feeding is not associated with fasting glucose or insulin resistance at 11.5 years of age. Grade: Limited

There is insufficient evidence to determine whether or not there is a relationship between shorter versus longer durations of exclusive human milk feeding and type 2 diabetes, prediabetes, and HbA1c throughout the lifespan, and fasting glucose and insulin resistance at ages other than 11.5 years. Grade: Grade Not Assignable 

Intensity, Proportion, or Amount of Human Milk Consumed by Mixed-Fed Infants

There is insufficient evidence to determine whether or not there is a relationship between feeding a lower versus higher intensity, proportion, or amount of human milk to mixed-fed infants and diabetes outcomes in offspring. Grade: Grade Not Assignable

Cardiovascular Disease

Ever vs Never Consuming Human Milk

Limited evidence suggests that never versus ever being fed human milk is associated with higher blood pressure, within a normal range, at 6 to 7 years of age. Grade: Limited

Evidence about the relationship of never versus ever being fed human milk with blood lipids in childhood was inconclusive, and there was insufficient evidence to determine the relationship of never versus ever being fed human milk with endpoint cardiovascular disease outcomes, blood pressure and blood lipids in adolescence or adulthood, metabolic syndrome, and arterial stiffness. Grade: Grade Not Assignable 

Duration of Any Human Milk Consumption Among Infants Fed Human Milk

Moderate evidence suggests that there is no association between the duration of any human milk feeding and blood pressure in childhood. Grade: Moderate

Evidence about the relationship of shorter versus longer durations of any human milk feeding with blood lipids in childhood and adulthood and with metabolic syndrome was inconclusive, and there was insufficient evidence to determine the relationship of shorter versus longer durations of any human milk feeding with endpoint cardiovascular disease outcomes, blood pressure in adolescence or adulthood, blood lipids in adolescence, and arterial stiffness. Grade: Grade Not Assignable 

Duration of Exclusive Human Milk Consumption

Limited evidence suggests that there is no association between the duration of exclusive human milk feeding and blood pressure in childhood or metabolic syndrome at 11.5 years of age. Most of the evidence comes from just one non-US sample assessed using a strong study design. Grade: Limited

There was insufficient evidence to determine the relationship of shorter versus longer durations of exclusive human milk feeding with endpoint cardiovascular disease outcomes, blood pressure in adolescence or adulthood, blood lipids, and metabolic syndrome at ages other than 11.5 years. Grade: Grade Not Assignable 

Intensity, Proportion, or Amount of Human Milk Consumed by Mixed-Fed Infants

There is no evidence to determine whether or not there is a relationship between feeding a lower versus higher intensity, proportion, or amount of human milk to mixed-fed infants and cardiovascular disease outcomes in offspring. Grade: Grade Not Assignable