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Nutrition During Lactation (1991)

Chapter: Front Matter

Suggested Citation:"Front Matter." Institute of Medicine. 1991. Nutrition During Lactation. Washington, DC: The National Academies Press. doi: 10.17226/1577.
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Nutrition During Lactation

Subcommittee on Nutrition During Lactation

Committee on Nutritional Status During Pregnancy and Lactation

Food and Nutrition Board

Institute of Medicine

National Academy of Sciences

NATIONAL ACADEMY PRESS
Washington, D.C.
1991

Suggested Citation:"Front Matter." Institute of Medicine. 1991. Nutrition During Lactation. Washington, DC: The National Academies Press. doi: 10.17226/1577.
×

National Academy Press
2101 Constitution Avenue, NW Washington, DC 20418

NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance.

This report has been reviewed by a group other than the authors according to procedures approved by a Report Review Committee consisting of members of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine.

The Institute of Medicine was chartered in 1970 by the National Academy of Sciences to enlist distinguished members of the appropriate professions in the examination of policy matters pertaining to the health of the public. In this, the Institute acts under both the Academy's 1863 congressional charter responsibility to be an adviser to the federal government and its own initiative in identifying issues of medical care, research, and education. Dr. Samuel O. Thier is president of the Institute of Medicine.

This study was supported by project no. MCJ 116011 from the Maternal and Child Health Program (Title V, Social Security Act), Health Resources and Services Administration, U.S. Department of Health and Human Services.

Library of Congress Cataloging-in-Publication Data

Institute of Medicine (U.S.). Subcommittee on Nutrition During Lactation.

Nutrition during lactation / Subcommittee on Nutrition During Lactation, Committee on Nutritional Status during Pregnancy and Lactation, Food and Nutrition Board, Institute of Medicine, National Academy of Sciences.

p. cm.

"This study was supported by project no MCJ 116011 from the maternal and child health program (Title V, Social Security Act), Health Resources and Services Administration, U.S. Dept. of Health and Human Services"—T.p. verso.

Includes bibliographical references and index.

ISBN 0-309-04391-3

1. Breast feeding—Health aspects. 2. Lactation—Nutritional aspects. 3. Milk, Human—Analysis. 4. Infants—Development. I. United States. Health Resources and Services Administration. II. Title.

[DNLM: 1. Breast Feeding. 2. Infant, Newborn. 3. Lactation. 4. Milk, Human—analysis. 5. Nutritional Requirements. 6. Nutritional Status. WP 825 I58]

RJ216.I54 1991

613.2'6—dc20

DNLM/DLC 90-13659

for Library of Congress CIP

Copyright © 1991 by the National Academy of Sciences

Printed in the United States of America

First Printing, February 1992

Second Printing, August 1993

Third Printing, March 1994

Fourth Printing, September 1996

Suggested Citation:"Front Matter." Institute of Medicine. 1991. Nutrition During Lactation. Washington, DC: The National Academies Press. doi: 10.17226/1577.
×

SUBCOMMITTEE ON NUTRITION DURING LACTATION

MARGIT HAMOSH (Chair),

Division of Developmental Biology and Nutrition, Georgetown University Medical Center, Washington, D.C.

KATHRYN G. DEWEY,

Department of Nutrition, University of California, Davis, California

CUTBERTO GARZA,

Division of Nutritional Sciences, Cornell University, Ithaca, New York

ARMOND S. GOLDMAN,

Department of Pediatrics, Division of Immunology/Allergy, The University of Texas Medical Branch, Galveston, Texas

RUTH A. LAWRENCE,

Department of Pediatrics, School of Medicine and Dentistry, University of Rochester, Rochester, New York

MARY FRANCES PICCIANO,

Department of Nutrition, The Pennsylvania State University, University Park, Pennsylvania

SARA A. QUANDT,

Department of Anthropology, University of Kentucky, Lexington, Kentucky

KATHLEEN M. RASMUSSEN,

Division of Nutritional Sciences, Cornell University, Ithaca, New York

DAVID RUSH,

Epidemiology Program, USDA Human Nutrition Research Center at Tufts University, Boston, Massachusetts

Staff:

CAROL WEST SUITOR, Study Director

YVONNE L. BRONNER, Research Associate

MARIAN M. F. MILLSTONE, Research Assistant (until July 1990)

GERALDINE KENNEDO, Senior Secretary

WILHELMENA TAMALE, Senior Secretary (until August 1990)

Suggested Citation:"Front Matter." Institute of Medicine. 1991. Nutrition During Lactation. Washington, DC: The National Academies Press. doi: 10.17226/1577.
×

COMMITTEE ON NUTRITIONAL STATUS DURING PREGNANCY AND LACTATION

ROY M. PITKIN (Chair),

Department of Obstetrics and Gynecology, School of Medicine, University of California, Los Angeles, California

BARBARA ABRAMS,

Program in Public Health Nutrition, School of Public Health, University of California, Berkeley, California

LINDSAY ALLEN,

Department of Nutritional Sciences, University of Connecticut, Storrs, Connecticut

JERE D. HAAS,

Division of Nutritional Sciences, Cornell University, Ithaca, New York

MARGIT HAMOSH,

Division of Developmental Biology and Nutrition, Georgetown University Medical Center, Washington, D.C.

FRANCIS E. JOHNSTON,

Department of Anthropology, University of Pennsylvania, Philadelphia, Pennsylvania

JANET C. KING,

Department of Nutritional Sciences, University of California, Berkeley, California

CHARLES MAHAN,

Department of Health and Rehabilitative Services, State Health Office, Tallahassee, Florida

KATHLEEN M. RASMUSSEN,

Division of Nutritional Sciences, Cornell University, Ithaca, New York

JOHN W. SPARKS,

Department of Pediatrics, School of Medicine, University of Colorado, Denver, Colorado

MERVYN W. SUSSER,

Sergievsky Center, Columbia University, New York, New York

Staff

CAROL WEST SUITOR, Study Director

YVONNE L. BRONNER, Research Associate

VIRGINIA H. LAUKARAN, Senior Staff Officer (until August 1988)

CHESSA K. LUTTER, Program Officer (until August 1988)

MARIAN M. F. MILLSTONE, Research Assistant (until July 1990)

WILHELMENA TAMALE, Senior Secretary (until August 1990)

GERALDINE KENNEDO, Senior Secretary

Suggested Citation:"Front Matter." Institute of Medicine. 1991. Nutrition During Lactation. Washington, DC: The National Academies Press. doi: 10.17226/1577.
×

FOOD AND NUTRITION BOARD

RICHARD J. HAVEL (Chairman),

Cardiovascular Research Institute, University of California School of Medicine, San Francisco, California

DONALD B. McCORMICK (Vice Chairman),

Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia

EDWIN L. BIERMAN,

Division of Metabolism, Endocrinology, and Nutrition, University of Washington School of Medicine, Seattle, Washington

EDWARD J. CALABRESE,

Environmental Health Program, Division of Public Health, University of Massachusetts, Amherst, Massachusetts

DORIS H. CALLOWAY,

University of California, Berkeley, California

DeWITT GOODMAN,

Institute of Human Nutrition, Columbia University, New York, New York

M.R.C. GREENWOOD,

University of California, Davis, California

JOAN D. GUSSOW,

Department of Nutrition Education, Teachers College, Columbia University, New York, New York

JOHN E. KINSELLA,

Institute of Food Science, Cornell University, Ithaca, New York

LAURENCE N. KOLONEL,

Cancer Center of Hawaii, University of Hawaii, Honolulu, Hawaii

REYNALDO MARTORELL,

Food Research Institute, Stanford University, Stanford, California

WALTER MERTZ,

Human Nutrition Research Center, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, Maryland

MALDEN C. NESHEIM,

Office of the Provost, Cornell University, Ithaca, New York

JOHN LISTON (Ex Officio),

Division of Food Science, School of Fisheries, College of Ocean and Fishery Sciences, University of Washington, Seattle, Washington

ARNO G. MOTULSKY (Ex Officio),

Center for Inherited Diseases, University of Washington, Seattle, Washington

ROY M. PITKIN (Ex Officio),

Department of Obstetrics and Gynecology, School of Medicine, University of California, Los Angeles, California

Staff

SUSHMA PALMER, Director (until September 1, 1989)

ALVIN G. LAZEN, Interim Director (September 5, 1989 to April 15, 1990)

CATHERINE E. WOTEKI, Director (beginning April 16, 1990)

FRANCES M. PETER, Deputy Director (until August 10, 1990)

SHIRLEY ASH, Financial Specialist

UTE HAYMAN, Administrative Assistant

Suggested Citation:"Front Matter." Institute of Medicine. 1991. Nutrition During Lactation. Washington, DC: The National Academies Press. doi: 10.17226/1577.
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Suggested Citation:"Front Matter." Institute of Medicine. 1991. Nutrition During Lactation. Washington, DC: The National Academies Press. doi: 10.17226/1577.
×

Preface

The biological importance of milk to all mammals, including humans, is evident from historical and physiologic perspectives. The survival of human infants depended on breastfeeding until early in the twentieth century when substitutes for human milk were developed, leading to a marked decrease in breastfeeding. Subsequent reports of lower morbidity and mortality among breastfed infants compared with formula-fed infants stimulated a reexamination of infant feeding practices. Questions have also been raised concerning the role of breastfeeding in promoting optimal infant growth, nutritional well-being of the infant, and bonding between mother and infant. Relatively little attention has been given to the mother and her needs.

Growing concerns among health professionals led to the first Surgeon General's Report, Healthy People: The Surgeon General's Report on Health Promotion and Disease Prevention (Department of Health, Education, and Welfare, 1979), and subsequently to publication of Promoting Health/Preventing Disease: Objectives for the Nation (Department of Health and Human Services [DHHS], 1980). The latter report set breastfeeding of 75% of all infants at hospital discharge and 35% at 6 months of age as an objective to be attained by 1990. Shortly thereafter, the Surgeon General's Workshop on Breastfeeding and Human Lactation further emphasized that objective and provided a framework for its implementation. The breastfeeding objective has not yet been achieved; in fact, the rate of breastfeeding at hospital discharge has decreased since the time of the Surgeon General's Workshop. Factors such as lack of specific policies for paid maternity leave, lack of child care facilities at the mother's place of employment, or lack of adequate facilities for pumping and storing

Page viii Cite
Suggested Citation:"Front Matter." Institute of Medicine. 1991. Nutrition During Lactation. Washington, DC: The National Academies Press. doi: 10.17226/1577.
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human milk might have contributed to the failure to reach the breastfeeding objective. The objective is reaffirmed and expanded in the Year 2000 Objectives for the Nation (DHHS, 1990).

Since 1980 there has been a marked increase in research on human milk, with special emphasis on its composition and role in promoting or sustaining the well-being and development of the infant. Six workshops on human milk and lactation were sponsored by the National Institute of Child Health and Human Development between 1982 and 1990. The third workshop was dedicated to maternal and environmental factors that affect human lactation, but the influence of maternal nutrition on lactation was reviewed only briefly.

Many studies of maternal and child nutrition have been conducted by committees of the Food and Nutrition Board under the sponsorship of the Office of Maternal and Child Health of the DHHS. However, the study reported in this volume is the first one directed specifically toward maternal nutrition during lactation.

Although great progress has been made in understanding the process of lactation and in characterizing and quantitating the composition of human milk, less progress has been made in linking the nutritional status of lactating women with various outcomes of breastfeeding. The subcommittee carefully examined evidence pertaining to the demographics of breastfeeding; lactation performance, including milk volume, duration of lactation, and milk composition; infant outcomes such as nutritional status, growth, development, morbidity, and mortality; and maternal long-term health outcomes. Special effort was made to search for studies to investigate the impact of maternal nutrition on these outcomes and studies of the effects of breastfeeding on maternal nutrition.

This volume provides information that will help researchers, students, and health care providers understand how nutrition of healthy women relates to various outcomes of lactation in the context of many other contributing factors. It is also intended to aid in formulating guidelines for clinical application in the United States. Finally, the report highlights gaps in knowledge and recommends directions for further research.

ORGANIZATION OF THIS REPORT

This volume begins with a summary of the report and its principal recommendations. Chapter 3 addresses the question, "Who is breastfeeding?," identifying breastfeeding rates in the United States by different demographic characteristics (such as age, ethnic background, region of the country, and employment status). It also provides a historical perspective of the incidence and duration of breastfeeding in the past century.

Chapter 4 examines anthropometric, biochemical, and dietary methods for assessing the nutritional status of lactating women and points out their uses and limitations. Since most interventions designed to improve nutritional status

Suggested Citation:"Front Matter." Institute of Medicine. 1991. Nutrition During Lactation. Washington, DC: The National Academies Press. doi: 10.17226/1577.
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act to increase intake of nutrients in short supply in the diet, the subcommittee tabulated and interpreted nutrient intake data from studies of lactating women. Chapters 5 and 6 contain discussions of the volume and composition of human milk and explain factors that must be considered when evaluating the impact of maternal nutrition on these two lactation outcomes. These chapters also provide the basis for estimating the range of the mother's nutrient losses resulting from breastfeeding.

Although infant growth, development, and health are key outcomes of breastfeeding, the effects of maternal nutrition during lactation on these outcomes have been largely ignored in the literature. To the extent possible, Chapter 7 reports links between the nutrition of the mother and the nutrition and growth of the nursing infant. Since a slower than expected rate of infant weight gain may be given as a reason to discontinue breastfeeding, the subcommittee paid special attention to the assessment of the growth of breastfed infants. The possibility that maternal nutrition may influence infant health through altered immunologic function and the links between maternal food intake while lactating and infant health are also considered in Chapter 7 as they relate to allergic diseases and environmental toxins. To provide a balanced overview of infant health, the risk of transmission of infectious agents via human milk and the presence of drugs in human milk are also covered. In addition, there is brief mention of the development of obesity and atherosclerosis in later life in relation to the method of infant feeding.

Chapter 8 explores ways that maternal health can be influenced by lactation, with special emphasis on obesity, osteoporosis, and breast cancer, as well as the impact of lactation on ovulation and fertility. In Chapter 9, information from preceding chapters is synthesized in a discussion of ways to meet the nutrient needs of lactating women. Chapter 10 includes a brief review of recent research recommendations concerning lactation and breastfeeding and then presents the subcommittee's recommendations for research concerning nutrition during lactation. The conclusions and recommendations of the subcommittee are presented in the Summary, Chapter 1.

ACKNOWLEDGMENTS

The subcommittee acknowledges the outstanding contribution of Carol Suitor, Study Director for this report. Her dedication, skill, and attention to all aspects of this report have been invaluable at all stages of its preparation.

The committee and subcommittee also appreciate the support provided by many other members of the Food and Nutrition Board staff, especially Dr. Alvin Lazen, Dr. Catherine Woteki, Mrs. Frances Peter, Dr. Yvonne Bronner, Ms. Marian Millstone, Ms. Wilhelmena Tamale, and Ms. Geraldine Kennedo. Mr. Michael Hayes ably served as copy editor.

The subcommittee benefited from advice and suggestions provided by

Suggested Citation:"Front Matter." Institute of Medicine. 1991. Nutrition During Lactation. Washington, DC: The National Academies Press. doi: 10.17226/1577.
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the Committee on Nutritional Status During Pregnancy and Lactation, from the sharing of information with the Subcommittee on Nutritional Status and Weight Gain During Pregnancy and the Subcommittee on Dietary Intake and Nutrient Supplements During Pregnancy, and from the assistance provided by the Food and Nutrition Board and its Subcommittee on the Tenth Edition of the Recommended Dietary Allowances.

Many people made important contributions to this combined report by giving presentations, providing the subcommittees with data or special written reports or analyses, sharing their views during workshops, commenting on drafts, or otherwise serving as resource persons. In particular, the committee and subcommittees wish to thank Dr. Thomas A. Arcury, University of Kentucky; Dr. Kenneth Brown, University of California, Davis; Ms. Becky Catey, Ross Laboratories; Dr. Catherine Cowell, Bureau of Nutrition, City of New York; Dr. Jan Dodds, Bureau of Nutrition, New York State; Dr. J. David Erickson, Centers for Disease Control; Ms. Linda Friedman, University of Rochester School of Medicine and Dentistry; Dr. Jean-Pierre Habicht, Cornell University; Dr. Suzanne Harris, Food and Consumer Services, U.S. Department of Agriculture (USDA); Mr. Jay Hirshman, Food and Nutrition Service, USDA; Ms. Patricia Jensen, Santa Clara County Department of Health, California; Ms. Lynn Kuba, Childbirth Educator, Fairfax County, Va.; Ms. Alice Lenihan, National Association of WIC (Supplemental Food Program for Women, Infants, and Children) Directors; Ms. Brenda Lisi, Food and Nutrition Service, USDA; Ms. Ruth Lubic, Maternity Center Association, New York City; Ms. Shelly Marks, Harbor University of California at Los Angeles Medical Center; Dr. Gilbert Martinez, Ross Laboratories; Dr. Margaret Neville, University of Colorado; Dr. Alan S. Ryan, Ross Laboratories; Dr. Rebecca Stoltzfus, Cornell University; Dr. Rita Thomas, Bristol-Myers; and Ms. Colette Zyrkowski, Centers for Disease Control.

ROY M. PITKIN

Chair

Committee on Nutritional Status During Pregnancy and Lactation

MARGIT HAMOSH

Chair

Subcommittee on Nutrition During Lactation

Suggested Citation:"Front Matter." Institute of Medicine. 1991. Nutrition During Lactation. Washington, DC: The National Academies Press. doi: 10.17226/1577.
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5

 

Milk Volume

 

80

   

Measurement of Milk Volume

 

81

   

Normal Range of Milk Intake and Production

 

81

   

Breast Development and Physiology

 

83

   

Infant Factors Influencing Milk Production and Transfer

 

84

   

Maternal Factors

 

87

   

Conclusions

 

103

   

Recommendations for Clinical Practice

 

104

   

References

 

105

6

 

Milk Composition

 

113

   

Characteristics of Human Milk

 

113

   

Methodologic Issues

 

115

   

Origin of Milk Constituents

 

120

   

Maternal Nutrition and the Composition of Human Milk

 

121

   

Constituents of Human Milk with Other Biologic Functions

 

132

   

Summary

 

140

   

Conclusions

 

140

   

Recommendations for Clinical Practice

 

140

   

References

 

141

7

 

Infant Outcomes

 

153

   

Infant Nutrition: Vitamins and Minerals

 

154

   

Growth and Development

 

161

   

Breastfeeding and Morbidity

 

166

   

Breastfeeding and Mortality

 

172

   

Medications, Legal and Illegal Drugs, and Environmental Agents

 

175

   

Conclusions

 

179

   

Recommendations for Clinical Practice

 

180

   

References

 

182

8

 

Maternal Health Effects of Breastfeeding

 

197

   

Short-Term Health Effects

 

198

   

Long-Term Health Effects

 

201

   

Conclusions

 

208

   

References

 

208

9

 

Meeting Maternal Nutrient Needs During Lactation

 

213

   

What Are the Nutritional Demands of Lactation?

 

213

   

Can Nutrient Needs During Lactation Be Met by Usual Dietary Intake Alone?

 

220

   

Food Guidance for Lactating Women

 

229

Suggested Citation:"Front Matter." Institute of Medicine. 1991. Nutrition During Lactation. Washington, DC: The National Academies Press. doi: 10.17226/1577.
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Nutrition During Lactation

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On the basis of a comprehensive literature review and analysis, Nutrition During Lactation points out specific directions for needed research in understanding the relationship between the nutrition of healthy mothers and the outcomes of lactation. Of widest interest are the committee's clear-cut recommendations for mothers and health care providers.

The volume presents data on who among U.S. mothers is breastfeeding, a critical evaluation of methods for assessing the nutritional status of lactating women, and an analysis of how to relate the mother's nutrition to the volume and composition of the milk.

Available data on the links between a mother's nutrition and the nutrition and growth of her infant and current information on the risk of transmission through breastfeeding of allergic diseases, environmental toxins, and certain viruses (including the HIV virus) are included. Nutrition During Lactation also studies the effects of maternal cigarette smoking, drug use, and alcohol consumption.

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