Nutrition Volume 17, Number 6, 2001 which adolescents were followed for 55 y. Overweight at adolescence was a strong predictor of coronary heart disease and atherosclerosis during adulthood, independent of body weight during adulthood.29 The presence of higher inflammation levels during childhood might in part explain the increased risk for cardiovascular disease in adulthood among obese children. Because overweight is associated with various risk factors among children, successful prevention and treatment of obesity in childhood might reduce the adult incidence of cardiovascular disease. Because obese children as young as 5 to 8 y already have higher inflammation levels and several risk factors for cardiovascular disease, efforts to prevent overweight should begin in early childhood.
Marjolein Visser, PhD Institute for Research in Extramural Medicine Vrije Universiteit Amsterdam Netherlands
Editorial Opinions
20. 21.
22.
23.
24.
25.
26.
27.
REFERENCES 1. Chinn S, Rona RJ. Prevalence and trends in overweight and obesity in three cross sectional studies of British children, 1974 –94. BMJ 2001;322:24 2. MacKay AP, Fingerhut LA, Duran CR. Adolescent health chartbook. Health, United States, 2000. Hyattsville, MD: National Center for Health Statistics, 2000 3. Ogden CL, Troiano RP, Briefel RR, et al. Prevalence of overweight among preschool children in the United States, 1971 through 1994. Pediatrics 1997; 99(4). Available from: http://www.pediatrics.org/cgi/content/full/99/4/e1 4. Morrison JA, Sprecher DL, Barton BA, Waclawiw MA, Daniels SR. Overweight, fat patterning, and cardiovascular disease risk factors in black and white girls: the National Heart, Lung, and Blood Institute Growth and Health Study. J Pediatr 1999;135:458 5. Csabi G, Torok K, Jeges S, Molnar D. Presence of metabolic cardiovascular syndrome in obese children. Eur J Pediatr 2000;159:91 6. Freedman DS, Dietz WH, Srinivasan SR, Berenson GS. The relation of overweight to cardiovascular risk factors among children and adolescents: the Bogalusa Heart Study. Pediatrics 1999;103:1175 7. Cook DG, Mendall MA, Whincup PH, et al. C-reactive protein concentration in children: relationship to adiposity and other cardiovascular risk factors. Atherosclerosis 2000;149:139 8. Freedman DS, Burke GL, Harsha DW, et al. Relationship of changes in obesity to serum lipid and lipoprotein changes in childhood and adolescence. JAMA 1985;254:515 9. Visser M, Bouter LM, McQuillan GM, Wener MH, Harris TB. Low-grade systemic inflammation in overweight children. Pediatrics 2000;107(1). Available from: http://www/pediatrics.org/cgi/content/full/107/1/e13 10. Cook DG, Whincup PH, Miller G, et al. Fibrinogen and factor VII levels are related to adiposity but not fetal growth or social class in children aged 10 –11 years. Am J Epidemiol 1999;150:727 11. Shea S, Isasi CR, Couch S, et al. Relations of plasma fibrinogen level in children to measures of obesity, the (G⫺4553 A) mutation in the -fibrinogen promotor gene, and family history of ischemic heart disease. Am J Epidemiol 1999;150:737 12. Mendall MA, Patel P, Ballam L, Strachan D, Northfield TC. C reactive protein and its relation to cardiovascular risk factors: a population based cross-sectional study. Br Med J 1996;312:1061 13. Visser M, Bouter LM, McQuillan GM, Wener MH, Harris TB. Elevated C-reactive protein levels in overweight and obese adults. JAMA 1999;282:2131 14. Hak AE, Stehouwer CD, Bots ML, et al. Associations of C-reactive protein with measures of obesity, insulin resistance, and subclinical atherosclerosis in healthy, middle-aged women. Arterioscler Thromb Vasc Biol 1999;19:1986 15. Stary HC. Lipid and macrophage accumulations in arteries of children and the development of atherosclerosis. Am J Clin Nutr 2000;72(suppl):1297S 16. Purohit A, Ghilchik MW, Duncan L, et al. Aromatase activity and interleukin-6 production by normal and malignant breast tissues. J Clin Endocrinol Metab 1995;80:3052 17. Crichton MB, Nichols JE, Zhao Y, Bulun SE, Simpson ER. Expression of transcripts of interleukin-6 and related cytokines by human breast tumors, breast cancer cells, and adipose stromal cells. Mol Cell Endocrinol 1996;118:215 18. Mohamed-Ali V, Goodrick S, Rawesh A, et al. Subcutaneous adipose tissue releases interleukin-6, but not tumor necrosis factor-␣, in vivo. J Clin Endocrinol Metab 1997;82:4196 19. Fried SK, Bunkin DA, Greenberg AS. Omental and subcutaneous adipose tissues
28.
29.
481
of obese subjects release interleukin-6: depot difference and regulation by glucocorticoid. J Clin Endocrinol Metab 1998;83:847 Banks RE, Forbes MA, Shorr M, et al. The acute phase response in patients receiving subcutaneous IL-6. Clin Exp Immunol 1995;102:217 Papanicolaou DA, Wilder RL, Manolagas SC, Chrousos GP. The pathophysiologic roles of interleukin-6 in human disease. Ann Intern Med 1998;128: 127 Bastard JP, Jardel C, Delattre J, et al. Evidence for a link between adipose tissue interleukin-6 content and serum C-reactive protein concentrations in obese subjects. Circulation 1999;99:2221 Bastard JP, Jardel C, Bruckert E, et al. Elevated levels of interleukin 6 are reduced in serum and subcutaneous adipose tissue of obese women after weight loss. J Clin Endocrinol Metab 2000;85:3338 Danesh J, Collins R, Appleby P, Peto R. Association of fibrinogen, C-reactive protein, albumin, or leukocyte count with coronary heart disease. JAMA 1998; 279:1477 Schmidt MI, Duncan BB, Sharrett AR, et al. Markers of inflammation and prediction of diabetes mellitus in adults (Atherosclerosis Risk in Communities study): a cohort study. Lancet 1999;353:1649 DiPietro L, Mossberg HO, Stunkard AJ. A 40-year history of overweight children in Stockholm: life-time overweight, morbidity, and mortality. Int J Obes Rel Metab Disord 1994;18:585 Sinaiko AR, Donahue RP, Jacobs DR Jr, Prineas RJ. Relation of weight and rate of increase in weight during childhood and adolescence to body size, blood pressure, fasting insulin, and lipids in young adults. The Minneapolis Children’s Blood Pressure Study. Circulation 1999;99:1471 Vanhala MJ, Vanhala PT, Keina¨nen-Kiukaanniemi SM, Kumpusalo EA, Takala JK. Relative weight gain and obesity as a child predict metabolic syndrome as an adult. Int J Obes 1999;23:656 Must A, Jacques PF, Dallal GE, Bajema CJ, Dietz WH. Long-term morbidity and mortality of overweight adolescents. A follow-up of the Harvard Growth Study of 1922 to 1935. N Engl J Med 1992;327:1350
PII S00899-9007(01)00509-3
A Good Start in Life: Breast Is Best, but Complementary Foods Should Not Be Worse Optimum nutrition and feeding of infants and young children are among the most important determinants of their health, growth, and development. They can prevent malnutrition and early growth retardation, which are common in many parts of the world.1 Poorly fed children have higher rates and severity of enteric and other infections, and they are at greater risk of dying prematurely. There is evidence that poor fetal and infant nutrition have long-term health consequences and play a role in the genesis of some chronic non-communicable diseases in adults. Furthermore, micronutrient deficiencies, especially of iron and iodine, might be associated with delayed motor development and impaired cognitive function. Thus, improvements in the nutrition of young children are desirable, not only for their positive effects on physical health and growth but also to reduce the risk of infection, ensure optimal psychomotor development and school performance and, in the long-term, improve adult life opportunities, health, and productivity. The period of transition, from an exclusively milk diet to one in which an increasing variety of foods is required to satisfy nutritional needs, is a particularly vulnerable time. Despite recognition of the public-health importance of infant and young-child nutrition and feeding practices, there are few guidelines based on scientific evidence for this critical weaning period.2,3 The World Health Organization (WHO) is aiming to reach consensus on the optimum duration of exclusive breast feeding and age of introduction of complementary feeds and, with UNICEF, to develop a global strategy for infant and young-child feeding.4
Correspondence to: Lawrence Weaver, MD, Department of Child Health, University of Glasgow, Royal Hospital for Sick Children, Yorkhill, Glasgow G3 8SJ, UK. E-mail:
[email protected]
482
Editorial Opinions
BREAST FEEDING The past two decades have seen great progress in the promotion of breast feeding as the optimum way to feed babies. Belief that “breast is best” has been translated into public-health recommendations and policy, which come together in the WHO/UNICEF Baby Friendly Hospital Initiative (BFHI). This has been justified by the strong evidence of the benefits of breast feeding to mother and infant5,6 and our growing understanding of the physiology of lactation and suckling, is supported by the international code of marketing breast-milk substitutes, and encapsulated in the “ten steps” to successful breast feeding.7 The 1990s saw affirmation of these initiatives through the Innocenti Declaration, the growth of breast-feeding counseling, and consolidation of evidence for the importance of sound infant nutrition to lifelong health, particularly in vulnerable communities. Each year sees more maternity centers around the world achieving BFHI accreditation and with them a growing number of mothers starting and continuing to breast feed their babies for longer periods. From 12 baby-friendly hospitals in 1992, there are more than 16 000 worldwide. The importance of breast feeding for infant health has been firmly established in WHO and UNICEF global policies and guidelines. Human milk is uniquely suited to the nutrition and other needs of the growing infant. It is the sole and sufficient source of all nutrients, energy, and many non-nutritional substances during early infancy. Breast milk alone cannot support the nutrition and other needs of the growing infant past the age of 6 mo or so, even though it continues to make a significant nutritional and protective contribution thereafter.8 There comes a time when complementary (weaning) foods must be introduced into the diet to fill the gap between what is provided by milk and what the infant requires to meet its nutrition requirements. The age at which this need should theoretically start to be met appears to be later than that at which mothers in most countries generally do so.9 Whereas breast milk has a relatively uniform and unique composition and provides specific nutrients vital to the newborn infant (e.g., essential fatty acids and human-milk proteins), the nutritional quality of complementary foods is more heterogeneous. It is not easy to be sure that the latter always meet the infant’s changing and growing nutrition needs. Moreover, there is dietary diversity throughout the world, and the food preferences and intakes of infants differ within and between them.
COMPLEMENTARY FEEDING The complementary feeding period is a critical time for infant and child health. It is when growth faltering occurs in many children in the developing world, and when micronutrient deficiencies (e.g., iron, zinc, and vitamin D) are most common in the developing and developed worlds.10 There are other nutrition differences between the children of rich and poor countries that are related to the prevalence of infection, caring practices, family size and wealth, and risks of microbiologic contamination of home-prepared milks and foods. But nutritional needs, developmental physiology, and genetic and growth potentials are broadly similar for children wherever they are born.10,11 The complementary feeding period follows a period of exclusive milk feeding. It cannot be thought about alone. It is part of a continuum of nourishing the infant, and milk, preferably breast milk, should continue to be a major part of the diet during the first year. The question of when to begin complementary feeds has been the subject of heated public debate.12 The WHO is addressing this issue through a systematic review of available scientific evidence, which has been recently made available at: http://www.who.int/ inf-pr-2001/en/note2001-07.html. Complementary foods should be timely, adequate, safe, and appropriate, and the process of feeding must not neglect the needs, knowledge, and resources of the
Nutrition Volume 17, Number 6, 2001 caregiver.4 The time has come to extend our interest in feeding and nutrition beyond the early months of life, when the focus is largely on breast-feeding, forward into later infancy and early childhood. But to provide sensible and rational guidelines, the science base on which to formulate rational recommendations needs to be developed.
FEEDING AND NUTRITION OF INFANTS AND YOUNG CHILDREN A workshop of experts on infant and child nutrition from around the world, convened in 1999 by the International Pediatric Association and the Committee on Nutrition of ESPGHAN, sought to define research priorities in complementary feeding.13 At around the same time WHO and UNICEF started the process of developing a global strategy on infant and young-child feeding, which will be presented to the World Health Assembly in 2002. A first step was an international technical consultation held in March 2000 in Geneva,4 where it was suggested to focus on four key areas: exclusive breast feeding, complementary feeding, feeding in exceptionally difficult circumstances (emergencies and human immunodeficiency virus), and the obligations and responsibilities of governments and international organizations. The WHO published a review of the current scientific knowledge about complementary feeding in 1998,9 which focused on the needs of children born and cared for in the developing world. Based on the best available published evidence, it brought together the information needed to develop sound feeding recommendations and appropriate intervention programs to optimize children’s dietary intakes and enhance their nutrition status. More recently, also under the auspices of WHO and UNICEF, guidelines for the feeding and nutrition of infants and young children of Europe, with an emphasis on the former Soviet countries, have been published.14 They contain the scientific rationale for the development of nutrition and feeding guidelines from birth to the age of 3 y, and are designed to provide information that will help national experts, public-health professionals, and policy makers to develop or update their current national recommendations. Despite the wide range of socioeconomic conditions found between and within the countries of the world, many of those recommendations can be applied universally. The information found in these two WHO publications is especially applicable to the most vulnerable groups of infants and young children living in deprived conditions and poverty, such as ethnic minorities and children of low-income families.
NUTRITION, POVERTY, AND CARE IN EARLY LIFE AND HEALTH IN ADULTHOOD Safeguarding the nutrition of infants and feeding them well is primarily the responsibility of parents and other caregivers, and they too must be healthy and supported.15 Poor maternal and child health and care often coexist in poor environmental conditions, and the gap between rich and poor is widening in many countries.16 Thirty-two percent of the population of the WHO European Region is living in poverty and UNICEF estimates that more than 30% of the world’s preschool children (at least 150 million) are underweight or stunted.1 Reducing premature mortality and morbidity and thereby improving life expectancy should be achieved by improving the nutrition status of young children and their mothers. Optimum maternal diet will help to ensure the care and health of infants, and there is evidence that optimal fetal development has long-term health advantages by reducing the risks of coronary heart disease, hypertension, stroke, chronic bronchitis, obesity, and diabetes in adulthood.17 Where poor maternal nutrition is common, it is often
Nutrition Volume 17, Number 6, 2001 linked with low birth weight (⬍2500 g), prematurity, and high perinatal-mortality rates.18 Reduction in the number of low– birthweight infants and improvements in infant growth are likely to positively influence cognitive development and reduce the risks of adult ill health. Increasing awareness of this important area is reflected in the first World Congress on Fetal Origins of Adult Disease recently held in Mumbai, India.19 To achieve the best start in life, “breast is undoubtedly best” but complementary foods should not be worse. The precise time at which they should start is important but more vital is to establish a strong scientific foundation to recommendations for feeding infants and young children.9,13,14 This need is underlined by the growing inequities between the health, nutrition status, and survival of children in rich and poor counties.1,16 The challenge to those concerned with the formulation of guidelines for the feeding and nutrition of young children is to build on those for breast feeding and define recommendations for the complementaryfeeding period that are based on evidence and applicable to those born and living in rich and poor countries alike.
Lawrence Weaver, MD Department of Child Health Royal Hospital for Sick Children University of Glasgow Glasgow, Scotland, UK Kim Fleischer Michaelsen, MD Research Department of Human Nutrition The Royal Veterinary and Agricultural University Frederiksberg, Denmark REFERENCES 1. State of the world’s children. Focus on nutrition. New York: UNICEF, 1998 2. UK Department of Health. Weaning and the weaning diet. London: HMSO, 1994 3. Kleinman RF, ed. Pediatric nutrition handbook. Elk Grove, IL: American Academy of Pediatrics, 1998 4. World Health Organisation. Report of a technical consultation on infant and young child feeding. Themes, discussions and recommendations. Geneva: WHO (WHO/NHD/00.8), 2000 5. Heinig, MJ, Dewey KG. Health effects of breastfeeding for mothers: a critical review. Nutr Res Rev 1997;10:35 6. Heinig, MJ, Dewey KG. Health advantages of breastfeeding for infants: a critical review. Nutr Res Rev 1996;9:89 7. World Health Organisation. Evidence for the ten steps to successful breastfeeding. Geneva: WHO (WHO/CHD/98.9), 1998 8. Elsom R, Weaver LT. Does breast feeding beyond one year benefit children? Fetal Matern Med Rev 1999;11:163 9. Brown KH, Dewey KG, Allen LH. Complementary feeding of young children in developing countries: a review of current scientific knowledge. Geneva: WHO/ UNICEF/ORSTOM/UCDAVIS, 1998 10. Doherty CP, Reilly JJ, Patterson WF, Donaldson MDC, Weaver LT. Growth failure and malnutrition. In: Walker WA et al, eds. Pediatric gastrointestinal disease. Hamilton, Canada: Decker, 2000:12 11. Martorell RJ. The nature of child nutrition and its long term implications. Food Nutr Bull 1999;20:288 12. Ferriman A. WHO accused of stifling debate about infant feeding. Br Med J 2000;320:1362 13. IPA and ESPGHAN. Workshop on research priorities in complementary feeding. Pediatrics 2000;106:1271 14. Michaelsen KF, Weaver LT, Branca F, Robertson F. Feeding and nutrition of infants and young children. Copenhagen: World Health Organisation, 2000 15. Engle PL, Engle PL, Lhotska L, Armstrong H. The care initiative. Assessment, analysis and action to improve care for nutrition. New York: UNICEF, 1997 16. Victora CG, Vaughan JP, Barros FC, Silva AC, Tomasi E. Explaining trends in inequities: evidence from Brazilian child health studies. Lancet 2000;356: 1093 17. Weaver LT. The child is father of the man. Paediatricians should be more interested in adult health. Clin Med 2001;1:38
Editorial Opinions
483
18. Osrin D, de Costello AM. Maternal nutrition and fetal growth: practical issues in international health. Semin Neonatol 2000;5:209 19. Robinson R. The fetal origins of adult disease. Br Med J 2001;322:375
PII S0899-9007(01)00553-6
Night-Eating Syndrome in Obesity The night-eating syndrome (NES) is currently emerging as a potential candidate for a new diagnostic eating disorder. NES was first described in 1955 by Stunkard et al.1 in obese outpatients and was largely neglected for 30 y when interest in NES slowly reemerged. Although the definition of NES varies somewhat with investigators and even with the same investigators over time, the basic criteria of NES encompass skipping breakfast, consuming most food in the late evening and at night, and difficulty with falling or staying asleep.2 Those who eat at night because they work the night shift are usually excluded from the NES category, although they are at risk for weight gain.3 An NES subset has a sleep-related problem with awakenings from sleep to eat.4 With regard to this nocturnal eating subset, an anecdotal case may be informative. A 25-y-old obese woman complained to me that she was not losing weight on a 3762-J (900-kcal) liquidformula diet. When the possibility of night eating was raised, she at first denied it but then became aware of a pattern of night awakenings. She would first go to the bathroom and then stop in the kitchen on the way back to the bedroom. Because she lived with a large Italian family, she would usually find a big bowl of pasta in the refrigerator. She would lean over the sink with the bowl and scoop pasta with her hands into her mouth, without leaving any dirty utensils as evidence. Because the amount of pasta in the bowl was huge, no one in the family noticed food missing. Once she realized the night-eating habit, the patient was requested not to drink or eat for 3 h before retiring. This change markedly reduced the awakenings to micturate, and thereafter she began losing weight successfully. To study nocturnal eating more scientifically, we conducted an overnight sleep study with a 28-y-old severely obese man (body mass index ⫽ 65) who at first also denied night eating.5 Food was made available bedside in the form of numerous quarter sandwiches with various fillings, and a video camera was set up nearby. There were several spontaneous wakening episodes, reflected in the electroencephalogram, all accompanied by eating episodes, without any bathroom visits. Each time, the eating was rapid with large consumption. The patient appeared alert and carefully selected the desired quarter sandwiches. With the same patient, we further explored whether the amount consumed during the day would influence the amount eaten at night. We changed daytime intake by means of a formula diet providing 2508 or 7524 J (600 or 1800 kcal) on two different days, each at a volume of 900 mL, and then also provided quarter sandwiches at night. We observed a negative correlation between daytime and nighttime intake, with an imperfect adjustment in nighttime intake, reflecting about 50% of the difference in daytime energy intake. The results indicated that there is some regulation of nighttime intake and suggest that a very restrictive daily diet could stimulate nighttime intake. Indeed, nocturnal eating has been reported in patients with anorexia nervosa.4 Among obese individuals entering a weight-loss program, comparisons were made between those with and without NES.6,7 In one study, NES prevalence was greater among those with more severe obesity and among men.6 In another study, NES subjects
Correspondence to: Allan Geliebter, PhD, New York Obesity Research Center, St. Luke’s–Roosevelt Hospital, Columbia University College of Physicians and Surgeons, 1111 Amsterdam Avenue, New York, NY 10025, USA. E-mail:
[email protected]