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Feeding the normal infant, child and adolescent
PAEDIATRIC NUTRITION
Feeding the normal infant, child and adolescent
breastfeed increases the risk of gastroenteritis, respiratory and urinary tract infections, obesity in later childhood, juvenile-onset insulin-dependent diabetes mellitus and atopic disease.1 It also sets the stage for risk of chronic disease, and a lifelong increase in susceptibility to the development of chronic disease.2 Whereas during adulthood, any risk associated with poor dietary choice is a matter of individual judgement, during infancy and early childhood there is absolute dependency on the judgement of others. This dependency becomes less as the years pass, but habits set during the early years become embedded in individual behaviour and can be very difficult to modify. Infants should be given human milk as the sole source of dietary intake for the first 6 months of life, and as part of an increasingly varied diet up to 2 years of age. Other foods should be introduced to the diet from around 6 months of age, initially in small amounts and in a consistency that the infant can cope with, but increasingly as foods that are drawn from the family’s diet. By 3e5 years of age the diet of the child should be similar to that of the rest of the family. In societies where breastfeeding is accepted as the normal way in which infants are fed, there are clear health benefits that protect against malnutrition in all its forms. Changes in height and weight of an individual represent a summary statement of the adequacy of the diet over the preceding period and monitoring the growth of a child is the simplest way to determine whether it is being adequately fed. In 2006, the World Health Organization introduced growth standards, derived from the growth of normal children in preferred healthy environments, from six centres around the world. All infants and children grow similarly once they have the opportunity, and the range of variability in height and weight in healthy children is much less than is found in groups drawn from a wider population exposed to less healthy circumstances.3
Alan A Jackson
Abstract Normal infants and children from around the world, when placed in a healthy environment, grow and develop at a similar rate as a matter of course by effectively utilizing the energy and nutrients derived from the diet. The form in which food is best provided varies with age. Infants should be given human milk as the sole source of dietary intake for the first 6 months of life, and as part of an increasingly varied diet up to the age of 2 years. Other foods should be introduced to the diet from around 6 months of age, initially in small amounts and in a consistency that the infant can cope with. By 3 to 5 years of age the diet of the child should be similar to that of the rest of the family. Growth may fail if the food is limited in amount or of poor quality, or the child is exposed to frequent infections. This carries risk of increased infection and other measures of ill-health in the short term, and greater susceptibility to chronic non-infective disease during adult life. Poor feeding practices during infancy and childhood are associated with an enormous burden of ill-health, poor development and lost opportunity. There is broad agreement with clear international guidelines on how best to feed children.
Keywords adolescent; breastfeeding; children; diet; feeding; infants
Introduction A characteristic feature of infancy and childhood is the continuous and progressive changes associated with growth and development. The underlying processes that enable these changes are absolutely dependent upon the ready availability of energy and nutrients, ultimately derived from the diet. Any limitation in the amount or pattern of energy and nutrients constrains, limits or perverts this ordered progression with inevitable consequences for size, shape and function. Once a disordered pattern of growth has been established it can be very difficult or impossible to correct, thereby leaving a developmental scar. The scar may have trivial consequence, but can be sufficiently marked to modify the opportunity for health throughout life. The specific guidance on the preferred approach to feeding in infancy and the diet best suited to children and adolescents has not changed greatly over the past 20 years. What have changed substantially are the dietary patterns themselves and the evidence to show that poor dietary practice during the early years of life carries the potential for substantial risk of illhealth. This risk may be manifest in the short term: not to
Growth and development There has been a progressive increase in achieved adult height, a secular trend, across the industrially developed world for the past 150 years. This decade-on-decade progressive change appears to have ceased in some countries where achieved or achievable adult height has reached a plateau over the past 20 years at an average of 1.8 m. For those countries where adult height is not yet 1.8 m the secular trend continues. It has been noted that a plateau for adult height around 1.8 m occurs some 18e20 years after neonatal mortality has been reduced to less than 4/1000 live births.4 This plateau is taken to imply that the genetic potential for height has been achieved in these populations, and further suggests an important relationship between health during pregnancy, and the perinatal period, and ultimate height. Growth embraces a range of changes that include increased size and complexity of function in the body. Changes in size, height and weight, are readily captured, but are a summary of more complex changes in the absolute and relative growth of individual tissues and organs. At the cellular level, energy is required to fuel the processes that utilize macronutrients and micronutrients to enable function: metabolism. The sum total is a demand for energy and nutrients to enable these processes, which ultimately has to be satisfied by a dietary intake. The pattern of nutrients required to meet this demand
Alan A Jackson MA MD FRCP FRCPCH FRCPath is Professor of Human Nutrition and Director of the NIHR Biomedical Research Unit, Nutrition, Diet and Lifestyle, Southampton University Hospitals NHS Trust, UK. Competing interests: none declared.
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Ó 2010 Published by Elsevier Ltd.
PAEDIATRIC NUTRITION
Current situation
varies with time, depending upon the specific cellular and organ functions that need to be established and sustained at any time. Ultimately the energy and nutrients that enable growth and development have to be derived from the food obtained from the environment. At different ages food and nutrients are provided in different forms and amounts, but body reserves buffer intermittent changes in the pattern of nutrient demands. During prenatal life nutrients are acquired by the fetus intravenously, through the umbilical vessels, and are therefore absolutely dependent upon the mothers ability to provide. During early postnatal life, this absolute dependence upon maternal provision is maintained during exclusive breastfeeding with increasing independence at later ages as a widening range of food is consumed in an appropriate form. The two transitions e from intravenous to oral, and from oral milk to a more diverse diet e represent periods of special vulnerability and, if not achieved successfully, of particular risk. At each stage, the quantity and quality of nutrients delivered determine the risk of ill-health in the short, medium and longer term. The nature and extent of the vulnerability, and the magnitude of the risk, can be seen readily as the extent of ill-health associated with a failure to negotiate these transitions effectively. Failure leads to impaired growth and development (stunting, limited neurocognitive development, increased risk of obesity and associated co-morbidities, altered immune and inflammatory responses and increased susceptibility to infection). Across the world, the risk and danger are expressed in different ways: in much of the developing world it is evident as under-5 mortality, whereas in developed countries the danger may be expressed more subtly as altered body composition and altered risk of chronic disease. Because growth is a continuum, every stage builds on the platform achieved for the earlier period, and growth before birth is the basis upon which growth during infancy is established. The nutritional well-being of a woman from the time of conception determines the well-being of the unborn baby, and women are encouraged to ensure that they have a healthy weight at the start of pregnancy. Women who are overweight or underweight are more likely to have babies that are poorly grown. It is also desirable not to start the first pregnancy until the mother’s own nutritional demand for growth has been completed, usually after 18 years of age. Vitamin D status is largely determined by exposure to sunshine and in much of the UK population this is marginal.5 For this reason, it is recommended that during pregnancy and lactation women take a supplement providing 10 mg each day. It has been shown that many neural tube defects can be prevented if women have adequate folate status at the time of conception. Thus, women who may become pregnant and those in the first 12 weeks of pregnancy are advised to take a supplement of folic acid, 400 mg daily.6 A higher dose of 4 mg/day is recommended for women at high risk of neural tube defect in their pregnancies. Experimental studies in animals and observational studies in humans have shown that relatively modest variation in the dietary pattern of the mother around conception and at all stages during pregnancy can exert a profound effect on the epigenotype of the offspring or baby leading to fixed phenotypic changes in its structure and function throughout life. This may explain an important part of differential susceptibility to later chronic disease, such as obesity or diabetes associated, which has been attributed to nutritional exposure in early life.7
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National diet and nutrition surveys (NDNS) of representative samples of the British population have been carried out for the past 25 years.8 Such surveys often fail to include the most deprived, most vulnerable sectors of society, and may be confounded by misreporting; however, the most recent study of adults in 2000 shows that, in young adults, the quality of the diet is on average poor, particularly with poor micronutrient intakes and excessive consumption of sugar (non-milk extrinsic sugars) associated with increasing prevalence of overweight and obesity. Young adults are particularly at risk of poor dietary intakes and nutritional status, as are those in the most deprived social groups. Thus, even before becoming pregnant, increasing numbers of young women are in a relatively poor nutritional state to meet the nutritional demands imposed by the pregnancy itself. Based on the NDNS, dietary patterns during childhood (1½e18 years) leave considerable room for improvement. The mean consumption of fruits and vegetables is less than half that recommended, and 20% of those in the survey did not consume any fruit, other than fruit juice, during the week of the survey itself. The mean consumption of oily fish was less than 0.1 portion per week. The consumption of sugars exceeded recommendations (11% of total energy) with the mean intake up to 19% of food energy, derived chiefly from soft drinks. Consumption of non-starch polysaccharides was less than desirable. The intake of vitamins and minerals, such as some B vitamins, magnesium, potassium, calcium, zinc and iodine, was poor. As many as 20% of girls had poor iron status, based on measures of intake, markers of iron status and anaemia. Amongst those aged 15e18 years, reported consumption of alcohol was 9 units per week in boys and 7 units per week in girls. For children aged 1½e4½, non-prescribed supplements were being taken by 20%, mainly as vitamins A, C and D. Infant feeding surveys have been carried out since 1975. The most recent, conducted in 2005, provided national estimates of breastfeeding incidence and prevalence and information about weaning practices.9 This showed some improvement in breastfeeding initiation rates in 2005 (76%) compared with 2000 (69%), and both the prevalence and duration of breastfeeding had increased across the UK. Young mothers and mothers from low socioeconomic groups are least likely to adopt recommended feeding practices and the greatest increases were seen in older mothers, those from higher socioeconomic groups and those with higher educational profiles. There are no national surveys for food intakes during pregnancy, but detailed information on intakes before and during pregnancy are available from studies such as the Southampton Women’s Survey, which has also provided evidence on the consumption patterns of infants and young children.10e12 These data are consistent with the national surveys, showing that current dietary practices in the UK of women before and during pregnancy exhibit wide variation, with significant proportions failing to consume a dietary pattern consistent with good health. There is a wide social gradient in dietary patterns that can be marked by the extent of maternal education attainment. Women who make poor dietary choices for themselves also tend to make poor dietary choices for their children during infancy and childhood. This identifies households where poor dietary choice tends to track from early life and is passed on from one generation to another.
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Ó 2010 Published by Elsevier Ltd.
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Recommendations
emphasis on the need for support from health professionals, the development and maintenance of appropriate services, active support for breastfeeding, including the availability of appropriate facilities for breastfeeding and a wider environment that is more supportive.
For many years the government has recognized the nutritional vulnerability of young children and has had in place broad strategies to provide a measure of protection. Specific guidance, provided in 1994, included advice on breastfeeding and the introduction of specific foods during weaning, training of health professionals, and clear advice and guidance to the public. A Welfare Food Scheme had been introduced in 1940 as a wartime measure to help ensure an adequate diet under rationing. It continued in the post-war period to provide milk and vitamin supplements to pregnant and lactating women and their children up to the age of 5 years. The Scheme was introduced to ensure the early identification and treatment of those failing to thrive for nutritional reasons. The Welfare Food Scheme was reviewed in 199913 and the reforms recommended within that review were incorporated into national policy as a new initiative, under ‘Healthy Start’ in 2002 (Table 1). This was one important mechanism through which nutritional support could be provided to those at greatest risk through poverty. The scheme places
International situation The world is faced with the double burden of malnutrition, overweight and underweight, both of which are associated with poor micronutrient status; each has its genesis in early life experience. The two conditions may be present at the same time in the same country, the same community and even the same household, and at different times in the same person. Across the world, undernutrition continues to be a major cause of death and disability for young children, accounting for one-third of all deaths and a 20% loss of healthy life-years. It is estimated that exclusive breastfeeding for the first 6 months of life might prevent up to half of all malnutrition and reduce deaths in children under 5 years of age by 11%. The deaths of more than half a million of such children could be prevented by adequate and timely complementary feeding along with continual breastfeeding for up to 2 years or beyond. On the other hand, the direct benefits over a lifetime related to the prevention of obesity may be less secure but are considered to be substantial. Worldwide malnutrition accounts for 11% of the global burden of disease, leading to long-term poor health and disability, and poor educational and developmental outcomes. There are 178 million children who are underweight worldwide and 20 million suffer from the most deadly form of severe acute malnutrition each year. It is estimated that nutritional risk factors, including underweight, suboptimal breastfeeding, and vitamin and mineral deficiencies, particularly of vitamin A, iron, iodine and zinc, are responsible for 3.9 million deaths (35% of total deaths) and 144 million disability-adjusted life years (33% of total disability-adjusted life years) in children less than 5 years old. Children under 2 years of age are most affected by undernutrition and 90% of stunted children live in 36 countries. Inappropriate feeding practices and their consequences are major obstacles to attaining sustainable socioeconomic development and poverty reduction. There are wide social and geographical differences in infant and young child feeding practices, which in part account for the marked social gradients in health and ill-health in society. Weaning practices and the introduction of complementary foods bear a direct relationship to the dietary practices of the family into which the baby is born. Poor dietary practices that predispose to adiposity can already be embedded by the first birthday, setting growth on a trajectory which may be very difficult to modify. In 2000, the governments of the world adopted a resolution at the UN for a strategy to improve the situation, known as the Millennium Development Goals (MDG) (Table 2). The MDG challenges, to be achieved by 2015, are all directly or indirectly related to better nutritional practice at vulnerable periods of the life-cycle. The Global strategy for Infant and Young Child Feeding is one important element of this ambitious agenda (http://apps.who.int/gb/ebwha/ pdf_files/EB126/B126_R5-en.pdf), with a recommitment given during the 63rd World Health Assembly, in January 2010 (http:// apps.who.int/gb/ebwha/pdf_files/EB126/B126_9-en.pdf). The underlying challenges of infant and young child feeding are exacerbated by infections, such as HIV, malaria and tuberculosis,
Healthy Start has replaced the Welfare Food Scheme across the UK (http://www.healthystart.nhs.uk/) What’s the role of health professionals? Healthy Start is a tool for health professionals to help you identify pregnant women and families who may need extra help and support to breastfeed and to have a healthier lifestyle. This could help you achieve national and local public health goals. Your role is to give appropriate health and lifestyle advice about diet in pregnancy, infant feeding, weaning and the benefits of milk, fresh fruit and vegetables and vitamin supplementation. The new scheme: C includes fruit and vegetables as well as milk and infant formula milk C supports breastfeeding C promotes uptake of vitamin supplements C encourages earlier and closer contact between health professionals and families from disadvantaged groups. Recommendations for infants and children The UK health departments recommend a daily dose of vitamins A, C and D for all: C breastfed infants from 6 months (or from 1 month if there is any doubt about the mother’s vitamin status during pregnancy) C formula-fed infants who are over 6 months and taking less than 500 ml infant formula per day. C children under 5 years of age This recommendation is particularly important for children who are picky or fussy eaters, those of Asian, African, Afro-Caribbean or Middle Eastern origin and those living in northern areas of the UK.1 Recommendations for women UK health departments recommend: C 10 mg of vitamin D each day for pregnant and breastfeeding women1 C 400 mg of folic acid for women who may become pregnant and up until the 12th week of pregnancy.2 Table 1
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excess plays on the vulnerability of children and has not yet been adequately addressed by society. A
Millennium Development Goals: what are the Millennium Development Goals? (http://www.undp.org/mdg/ basics.shtml) The Millennium Development Goals (MDGs) are the most broadly supported, comprehensive and specific development goals the world has ever agreed upon. These eight time-bound goals provide concrete, numerical benchmarks for tackling extreme poverty in its many dimensions. They include goals and targets on income poverty, hunger, maternal and child mortality, disease, inadequate shelter, gender inequality, environmental degradation and the Global Partnership for Development. Adopted by world leaders in the year 2000 and set to be achieved by 2015, the MDGs are both global and local, tailored by each country to suit specific development needs. They provide a framework for the entire international community to work together towards a common end e making sure that human development reaches everyone, everywhere. If these goals are achieved, world poverty will be cut by half, tens of millions of lives will be saved, and billions more people will have the opportunity to benefit from the global economy. The eight MDGs break down into 21 quantifiable targets that are measured by 60 indicators. C Eradicate extreme poverty and hunger C Achieve universal primary education C Promote gender equality and empower women C Reduce child mortality C Improve maternal health C Combat HIV/AIDS, malaria and other diseases C Ensure environmental sustainability C Develop a global partnership for development
REFERENCES 1 Dykes F. Infant feeding initiative: a report evaluating the breastfeeding practice projects 1999e2002. London: Department of Health, http://www.dh.gov.uk/en/Publicationsandstatistics/Publications/ PublicationsPolicyAndGuidance/DH_4084457; 2003. 2 Scientific Advisory Committee on Nutrition and Royal College of Paediatrics and Child Health. Application of WHO growth standards in the UK. London: The Stationery Office, http://www.rcpch.ac.uk/doc. aspx?id_resource¼2862; 2007. 3 World Health Organization, 2006. WHO technical consultation towards the development of a strategy for promoting optimal fetal development (Geneva, Switzerland, 2003.) (http://www.who.int/ nutrition/topics/fetal_dev_report_EN.pdf ). 4 Larnkaer A, Attrup Schrøder S, Schmidt IM, Hørby Jørgensen M, Fleischer Michaelsen K. Secular change in adult stature has come to a halt in northern Europe and Italy. Acta Paediatr 2006; 95: 754e5. 5 Scientific Advisory Committee on Nutrition. Update on Vitamin D. London: The Stationery Office, http://www.sacn.gov.uk/pdfs/sacn_position_ vitamin_d_2007_05_07.pdf. 6 Scientific Advisory Committee on Nutrition. Folate and disease prevention. London: The Stationery Office, http://www.sacn.gov.uk/ pdfs/folate_and_disease_prevention_report.pdf; 2006. 7 Burdge GC, Lillycrop KA. Nutrition, epigenetics, and developmental plasticity: implications for understanding human disease. Ann Rev Nutr 2010; 30: 315e39. 8 Scientific Advisory Committee on Nutrition. The nutritional wellbeing of the British population. London: The Stationery Office, http://www. sacn.gov.uk/pdfs/nutritional_health_of_the_population_final_oct_ 08.pdf; 2008. 9 Scientific Advisory Committee on Nutrition. Infant feeding survey 2005: a commentary on infant feeding practices in the UK. London: The Stationery Office, http://www.sacn.gov.uk/pdfs/sacn_ifs_paper_ 2008.pdf; 2008. 10 Robinson SM, Crozier SR, Borland SE, Hammond J, Barker DJ, Inskip HM. Impact of educational attainment on the quality of young women’s diets. Eur J Clin Nutr 2004; 58: 1174e80. 11 Robinson S, Marriott L, Poole J, et al. Southampton Women’s Survey Study Group. Dietary patterns in infancy: the importance of maternal and family influences on feeding practice. Br J Nutr 2007; 98: 1029e37. 12 Fisk CM, Crozier SR, Inskip HM, Godfrey KM, Cooper C, Robinson SM. The Southampton Women’s Survey Study Group. Influences on the quality of young children’s diets: the importance of maternal food choices. Br J Nutr 2010: 1e9 [Epub ahead of print]. 13 Department of Health. Committee on Medical Aspects of Food and Nutrition Policy. Report on health and social subjects 51. Scientific review of the Welfare Food Scheme. London: The Stationery Office, 2002.
Table 2
civil unrest and natural disasters, but the resource and knowledge to tackle these problems are available if the will is there for them to be deployed effectively. Health professionals carry a special responsibility in this regard, not only to deliver the services but also to act as advocates for infants and young children, members of the population who have no voice of their own and are entirely dependent upon the judgement and goodwill of others. There is evidence that early experience can have an important effect upon preferred tastes and flavours in later life, either in terms of dietary choices of mothers whilst breastfeeding or the types of foods offered during infancy and young childhood. This serves to emphasize the importance of parental ability to create an appropriate environment in which better choices are exercised as a matter of course by young children and as they mature. From a remarkably early age the pressures exerted by a wide range of marketing techniques, which includes advertising, have been shown to have a powerful influence on food choice which may be pernicious. The ready availability and active promotion of foods that contribute to unhealthy diets when consumed in
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Feeding the normal infant, child and adolescent
breastfeed increases the risk of gastroenteritis, respiratory and urinary tract infections, obesity in later childhood, juvenile-onset insulin-dependent diabetes mellitus and atopic disease.1 It also sets the stage for risk of chronic disease, and a lifelong increase in susceptibility to the development of chronic disease.2 Whereas during adulthood, any risk associated with poor dietary choice is a matter of individual judgement, during infancy and early childhood there is absolute dependency on the judgement of others. This dependency becomes less as the years pass, but habits set during the early years become embedded in individual behaviour and can be very difficult to modify. Infants should be given human milk as the sole source of dietary intake for the first 6 months of life, and as part of an increasingly varied diet up to 2 years of age. Other foods should be introduced to the diet from around 6 months of age, initially in small amounts and in a consistency that the infant can cope with, but increasingly as foods that are drawn from the family’s diet. By 3e5 years of age the diet of the child should be similar to that of the rest of the family. In societies where breastfeeding is accepted as the normal way in which infants are fed, there are clear health benefits that protect against malnutrition in all its forms. Changes in height and weight of an individual represent a summary statement of the adequacy of the diet over the preceding period and monitoring the growth of a child is the simplest way to determine whether it is being adequately fed. In 2006, the World Health Organization introduced growth standards, derived from the growth of normal children in preferred healthy environments, from six centres around the world. All infants and children grow similarly once they have the opportunity, and the range of variability in height and weight in healthy children is much less than is found in groups drawn from a wider population exposed to less healthy circumstances.3
Alan A Jackson
Abstract Normal infants and children from around the world, when placed in a healthy environment, grow and develop at a similar rate as a matter of course by effectively utilizing the energy and nutrients derived from the diet. The form in which food is best provided varies with age. Infants should be given human milk as the sole source of dietary intake for the first 6 months of life, and as part of an increasingly varied diet up to the age of 2 years. Other foods should be introduced to the diet from around 6 months of age, initially in small amounts and in a consistency that the infant can cope with. By 3 to 5 years of age the diet of the child should be similar to that of the rest of the family. Growth may fail if the food is limited in amount or of poor quality, or the child is exposed to frequent infections. This carries risk of increased infection and other measures of ill-health in the short term, and greater susceptibility to chronic non-infective disease during adult life. Poor feeding practices during infancy and childhood are associated with an enormous burden of ill-health, poor development and lost opportunity. There is broad agreement with clear international guidelines on how best to feed children.
Keywords adolescent; breastfeeding; children; diet; feeding; infants
Introduction A characteristic feature of infancy and childhood is the continuous and progressive changes associated with growth and development. The underlying processes that enable these changes are absolutely dependent upon the ready availability of energy and nutrients, ultimately derived from the diet. Any limitation in the amount or pattern of energy and nutrients constrains, limits or perverts this ordered progression with inevitable consequences for size, shape and function. Once a disordered pattern of growth has been established it can be very difficult or impossible to correct, thereby leaving a developmental scar. The scar may have trivial consequence, but can be sufficiently marked to modify the opportunity for health throughout life. The specific guidance on the preferred approach to feeding in infancy and the diet best suited to children and adolescents has not changed greatly over the past 20 years. What have changed substantially are the dietary patterns themselves and the evidence to show that poor dietary practice during the early years of life carries the potential for substantial risk of illhealth. This risk may be manifest in the short term: not to
Growth and development There has been a progressive increase in achieved adult height, a secular trend, across the industrially developed world for the past 150 years. This decade-on-decade progressive change appears to have ceased in some countries where achieved or achievable adult height has reached a plateau over the past 20 years at an average of 1.8 m. For those countries where adult height is not yet 1.8 m the secular trend continues. It has been noted that a plateau for adult height around 1.8 m occurs some 18e20 years after neonatal mortality has been reduced to less than 4/1000 live births.4 This plateau is taken to imply that the genetic potential for height has been achieved in these populations, and further suggests an important relationship between health during pregnancy, and the perinatal period, and ultimate height. Growth embraces a range of changes that include increased size and complexity of function in the body. Changes in size, height and weight, are readily captured, but are a summary of more complex changes in the absolute and relative growth of individual tissues and organs. At the cellular level, energy is required to fuel the processes that utilize macronutrients and micronutrients to enable function: metabolism. The sum total is a demand for energy and nutrients to enable these processes, which ultimately has to be satisfied by a dietary intake. The pattern of nutrients required to meet this demand
Alan A Jackson MA MD FRCP FRCPCH FRCPath is Professor of Human Nutrition and Director of the NIHR Biomedical Research Unit, Nutrition, Diet and Lifestyle, Southampton University Hospitals NHS Trust, UK. Competing interests: none declared.
MEDICINE 39:1
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Ó 2010 Published by Elsevier Ltd.
PAEDIATRIC NUTRITION
Current situation
varies with time, depending upon the specific cellular and organ functions that need to be established and sustained at any time. Ultimately the energy and nutrients that enable growth and development have to be derived from the food obtained from the environment. At different ages food and nutrients are provided in different forms and amounts, but body reserves buffer intermittent changes in the pattern of nutrient demands. During prenatal life nutrients are acquired by the fetus intravenously, through the umbilical vessels, and are therefore absolutely dependent upon the mothers ability to provide. During early postnatal life, this absolute dependence upon maternal provision is maintained during exclusive breastfeeding with increasing independence at later ages as a widening range of food is consumed in an appropriate form. The two transitions e from intravenous to oral, and from oral milk to a more diverse diet e represent periods of special vulnerability and, if not achieved successfully, of particular risk. At each stage, the quantity and quality of nutrients delivered determine the risk of ill-health in the short, medium and longer term. The nature and extent of the vulnerability, and the magnitude of the risk, can be seen readily as the extent of ill-health associated with a failure to negotiate these transitions effectively. Failure leads to impaired growth and development (stunting, limited neurocognitive development, increased risk of obesity and associated co-morbidities, altered immune and inflammatory responses and increased susceptibility to infection). Across the world, the risk and danger are expressed in different ways: in much of the developing world it is evident as under-5 mortality, whereas in developed countries the danger may be expressed more subtly as altered body composition and altered risk of chronic disease. Because growth is a continuum, every stage builds on the platform achieved for the earlier period, and growth before birth is the basis upon which growth during infancy is established. The nutritional well-being of a woman from the time of conception determines the well-being of the unborn baby, and women are encouraged to ensure that they have a healthy weight at the start of pregnancy. Women who are overweight or underweight are more likely to have babies that are poorly grown. It is also desirable not to start the first pregnancy until the mother’s own nutritional demand for growth has been completed, usually after 18 years of age. Vitamin D status is largely determined by exposure to sunshine and in much of the UK population this is marginal.5 For this reason, it is recommended that during pregnancy and lactation women take a supplement providing 10 mg each day. It has been shown that many neural tube defects can be prevented if women have adequate folate status at the time of conception. Thus, women who may become pregnant and those in the first 12 weeks of pregnancy are advised to take a supplement of folic acid, 400 mg daily.6 A higher dose of 4 mg/day is recommended for women at high risk of neural tube defect in their pregnancies. Experimental studies in animals and observational studies in humans have shown that relatively modest variation in the dietary pattern of the mother around conception and at all stages during pregnancy can exert a profound effect on the epigenotype of the offspring or baby leading to fixed phenotypic changes in its structure and function throughout life. This may explain an important part of differential susceptibility to later chronic disease, such as obesity or diabetes associated, which has been attributed to nutritional exposure in early life.7
MEDICINE 39:1
National diet and nutrition surveys (NDNS) of representative samples of the British population have been carried out for the past 25 years.8 Such surveys often fail to include the most deprived, most vulnerable sectors of society, and may be confounded by misreporting; however, the most recent study of adults in 2000 shows that, in young adults, the quality of the diet is on average poor, particularly with poor micronutrient intakes and excessive consumption of sugar (non-milk extrinsic sugars) associated with increasing prevalence of overweight and obesity. Young adults are particularly at risk of poor dietary intakes and nutritional status, as are those in the most deprived social groups. Thus, even before becoming pregnant, increasing numbers of young women are in a relatively poor nutritional state to meet the nutritional demands imposed by the pregnancy itself. Based on the NDNS, dietary patterns during childhood (1½e18 years) leave considerable room for improvement. The mean consumption of fruits and vegetables is less than half that recommended, and 20% of those in the survey did not consume any fruit, other than fruit juice, during the week of the survey itself. The mean consumption of oily fish was less than 0.1 portion per week. The consumption of sugars exceeded recommendations (11% of total energy) with the mean intake up to 19% of food energy, derived chiefly from soft drinks. Consumption of non-starch polysaccharides was less than desirable. The intake of vitamins and minerals, such as some B vitamins, magnesium, potassium, calcium, zinc and iodine, was poor. As many as 20% of girls had poor iron status, based on measures of intake, markers of iron status and anaemia. Amongst those aged 15e18 years, reported consumption of alcohol was 9 units per week in boys and 7 units per week in girls. For children aged 1½e4½, non-prescribed supplements were being taken by 20%, mainly as vitamins A, C and D. Infant feeding surveys have been carried out since 1975. The most recent, conducted in 2005, provided national estimates of breastfeeding incidence and prevalence and information about weaning practices.9 This showed some improvement in breastfeeding initiation rates in 2005 (76%) compared with 2000 (69%), and both the prevalence and duration of breastfeeding had increased across the UK. Young mothers and mothers from low socioeconomic groups are least likely to adopt recommended feeding practices and the greatest increases were seen in older mothers, those from higher socioeconomic groups and those with higher educational profiles. There are no national surveys for food intakes during pregnancy, but detailed information on intakes before and during pregnancy are available from studies such as the Southampton Women’s Survey, which has also provided evidence on the consumption patterns of infants and young children.10e12 These data are consistent with the national surveys, showing that current dietary practices in the UK of women before and during pregnancy exhibit wide variation, with significant proportions failing to consume a dietary pattern consistent with good health. There is a wide social gradient in dietary patterns that can be marked by the extent of maternal education attainment. Women who make poor dietary choices for themselves also tend to make poor dietary choices for their children during infancy and childhood. This identifies households where poor dietary choice tends to track from early life and is passed on from one generation to another.
59
Ó 2010 Published by Elsevier Ltd.
PAEDIATRIC NUTRITION
Recommendations
emphasis on the need for support from health professionals, the development and maintenance of appropriate services, active support for breastfeeding, including the availability of appropriate facilities for breastfeeding and a wider environment that is more supportive.
For many years the government has recognized the nutritional vulnerability of young children and has had in place broad strategies to provide a measure of protection. Specific guidance, provided in 1994, included advice on breastfeeding and the introduction of specific foods during weaning, training of health professionals, and clear advice and guidance to the public. A Welfare Food Scheme had been introduced in 1940 as a wartime measure to help ensure an adequate diet under rationing. It continued in the post-war period to provide milk and vitamin supplements to pregnant and lactating women and their children up to the age of 5 years. The Scheme was introduced to ensure the early identification and treatment of those failing to thrive for nutritional reasons. The Welfare Food Scheme was reviewed in 199913 and the reforms recommended within that review were incorporated into national policy as a new initiative, under ‘Healthy Start’ in 2002 (Table 1). This was one important mechanism through which nutritional support could be provided to those at greatest risk through poverty. The scheme places
International situation The world is faced with the double burden of malnutrition, overweight and underweight, both of which are associated with poor micronutrient status; each has its genesis in early life experience. The two conditions may be present at the same time in the same country, the same community and even the same household, and at different times in the same person. Across the world, undernutrition continues to be a major cause of death and disability for young children, accounting for one-third of all deaths and a 20% loss of healthy life-years. It is estimated that exclusive breastfeeding for the first 6 months of life might prevent up to half of all malnutrition and reduce deaths in children under 5 years of age by 11%. The deaths of more than half a million of such children could be prevented by adequate and timely complementary feeding along with continual breastfeeding for up to 2 years or beyond. On the other hand, the direct benefits over a lifetime related to the prevention of obesity may be less secure but are considered to be substantial. Worldwide malnutrition accounts for 11% of the global burden of disease, leading to long-term poor health and disability, and poor educational and developmental outcomes. There are 178 million children who are underweight worldwide and 20 million suffer from the most deadly form of severe acute malnutrition each year. It is estimated that nutritional risk factors, including underweight, suboptimal breastfeeding, and vitamin and mineral deficiencies, particularly of vitamin A, iron, iodine and zinc, are responsible for 3.9 million deaths (35% of total deaths) and 144 million disability-adjusted life years (33% of total disability-adjusted life years) in children less than 5 years old. Children under 2 years of age are most affected by undernutrition and 90% of stunted children live in 36 countries. Inappropriate feeding practices and their consequences are major obstacles to attaining sustainable socioeconomic development and poverty reduction. There are wide social and geographical differences in infant and young child feeding practices, which in part account for the marked social gradients in health and ill-health in society. Weaning practices and the introduction of complementary foods bear a direct relationship to the dietary practices of the family into which the baby is born. Poor dietary practices that predispose to adiposity can already be embedded by the first birthday, setting growth on a trajectory which may be very difficult to modify. In 2000, the governments of the world adopted a resolution at the UN for a strategy to improve the situation, known as the Millennium Development Goals (MDG) (Table 2). The MDG challenges, to be achieved by 2015, are all directly or indirectly related to better nutritional practice at vulnerable periods of the life-cycle. The Global strategy for Infant and Young Child Feeding is one important element of this ambitious agenda (http://apps.who.int/gb/ebwha/ pdf_files/EB126/B126_R5-en.pdf), with a recommitment given during the 63rd World Health Assembly, in January 2010 (http:// apps.who.int/gb/ebwha/pdf_files/EB126/B126_9-en.pdf). The underlying challenges of infant and young child feeding are exacerbated by infections, such as HIV, malaria and tuberculosis,
Healthy Start has replaced the Welfare Food Scheme across the UK (http://www.healthystart.nhs.uk/) What’s the role of health professionals? Healthy Start is a tool for health professionals to help you identify pregnant women and families who may need extra help and support to breastfeed and to have a healthier lifestyle. This could help you achieve national and local public health goals. Your role is to give appropriate health and lifestyle advice about diet in pregnancy, infant feeding, weaning and the benefits of milk, fresh fruit and vegetables and vitamin supplementation. The new scheme: C includes fruit and vegetables as well as milk and infant formula milk C supports breastfeeding C promotes uptake of vitamin supplements C encourages earlier and closer contact between health professionals and families from disadvantaged groups. Recommendations for infants and children The UK health departments recommend a daily dose of vitamins A, C and D for all: C breastfed infants from 6 months (or from 1 month if there is any doubt about the mother’s vitamin status during pregnancy) C formula-fed infants who are over 6 months and taking less than 500 ml infant formula per day. C children under 5 years of age This recommendation is particularly important for children who are picky or fussy eaters, those of Asian, African, Afro-Caribbean or Middle Eastern origin and those living in northern areas of the UK.1 Recommendations for women UK health departments recommend: C 10 mg of vitamin D each day for pregnant and breastfeeding women1 C 400 mg of folic acid for women who may become pregnant and up until the 12th week of pregnancy.2 Table 1
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excess plays on the vulnerability of children and has not yet been adequately addressed by society. A
Millennium Development Goals: what are the Millennium Development Goals? (http://www.undp.org/mdg/ basics.shtml) The Millennium Development Goals (MDGs) are the most broadly supported, comprehensive and specific development goals the world has ever agreed upon. These eight time-bound goals provide concrete, numerical benchmarks for tackling extreme poverty in its many dimensions. They include goals and targets on income poverty, hunger, maternal and child mortality, disease, inadequate shelter, gender inequality, environmental degradation and the Global Partnership for Development. Adopted by world leaders in the year 2000 and set to be achieved by 2015, the MDGs are both global and local, tailored by each country to suit specific development needs. They provide a framework for the entire international community to work together towards a common end e making sure that human development reaches everyone, everywhere. If these goals are achieved, world poverty will be cut by half, tens of millions of lives will be saved, and billions more people will have the opportunity to benefit from the global economy. The eight MDGs break down into 21 quantifiable targets that are measured by 60 indicators. C Eradicate extreme poverty and hunger C Achieve universal primary education C Promote gender equality and empower women C Reduce child mortality C Improve maternal health C Combat HIV/AIDS, malaria and other diseases C Ensure environmental sustainability C Develop a global partnership for development
REFERENCES 1 Dykes F. Infant feeding initiative: a report evaluating the breastfeeding practice projects 1999e2002. London: Department of Health, http://www.dh.gov.uk/en/Publicationsandstatistics/Publications/ PublicationsPolicyAndGuidance/DH_4084457; 2003. 2 Scientific Advisory Committee on Nutrition and Royal College of Paediatrics and Child Health. Application of WHO growth standards in the UK. London: The Stationery Office, http://www.rcpch.ac.uk/doc. aspx?id_resource¼2862; 2007. 3 World Health Organization, 2006. WHO technical consultation towards the development of a strategy for promoting optimal fetal development (Geneva, Switzerland, 2003.) (http://www.who.int/ nutrition/topics/fetal_dev_report_EN.pdf ). 4 Larnkaer A, Attrup Schrøder S, Schmidt IM, Hørby Jørgensen M, Fleischer Michaelsen K. Secular change in adult stature has come to a halt in northern Europe and Italy. Acta Paediatr 2006; 95: 754e5. 5 Scientific Advisory Committee on Nutrition. Update on Vitamin D. London: The Stationery Office, http://www.sacn.gov.uk/pdfs/sacn_position_ vitamin_d_2007_05_07.pdf. 6 Scientific Advisory Committee on Nutrition. Folate and disease prevention. London: The Stationery Office, http://www.sacn.gov.uk/ pdfs/folate_and_disease_prevention_report.pdf; 2006. 7 Burdge GC, Lillycrop KA. Nutrition, epigenetics, and developmental plasticity: implications for understanding human disease. Ann Rev Nutr 2010; 30: 315e39. 8 Scientific Advisory Committee on Nutrition. The nutritional wellbeing of the British population. London: The Stationery Office, http://www. sacn.gov.uk/pdfs/nutritional_health_of_the_population_final_oct_ 08.pdf; 2008. 9 Scientific Advisory Committee on Nutrition. Infant feeding survey 2005: a commentary on infant feeding practices in the UK. London: The Stationery Office, http://www.sacn.gov.uk/pdfs/sacn_ifs_paper_ 2008.pdf; 2008. 10 Robinson SM, Crozier SR, Borland SE, Hammond J, Barker DJ, Inskip HM. Impact of educational attainment on the quality of young women’s diets. Eur J Clin Nutr 2004; 58: 1174e80. 11 Robinson S, Marriott L, Poole J, et al. Southampton Women’s Survey Study Group. Dietary patterns in infancy: the importance of maternal and family influences on feeding practice. Br J Nutr 2007; 98: 1029e37. 12 Fisk CM, Crozier SR, Inskip HM, Godfrey KM, Cooper C, Robinson SM. The Southampton Women’s Survey Study Group. Influences on the quality of young children’s diets: the importance of maternal food choices. Br J Nutr 2010: 1e9 [Epub ahead of print]. 13 Department of Health. Committee on Medical Aspects of Food and Nutrition Policy. Report on health and social subjects 51. Scientific review of the Welfare Food Scheme. London: The Stationery Office, 2002.
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civil unrest and natural disasters, but the resource and knowledge to tackle these problems are available if the will is there for them to be deployed effectively. Health professionals carry a special responsibility in this regard, not only to deliver the services but also to act as advocates for infants and young children, members of the population who have no voice of their own and are entirely dependent upon the judgement and goodwill of others. There is evidence that early experience can have an important effect upon preferred tastes and flavours in later life, either in terms of dietary choices of mothers whilst breastfeeding or the types of foods offered during infancy and young childhood. This serves to emphasize the importance of parental ability to create an appropriate environment in which better choices are exercised as a matter of course by young children and as they mature. From a remarkably early age the pressures exerted by a wide range of marketing techniques, which includes advertising, have been shown to have a powerful influence on food choice which may be pernicious. The ready availability and active promotion of foods that contribute to unhealthy diets when consumed in
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