The Importance Of Child And Maternal Nutrition

Although the precise contribution of nutrition to maternal and infant health cannot yet be distinguished from genetic, environmental, or behavioural factors that affect risk, an inadequate diet during pregnancy increases the probability of a low birth weight (LBW) infant, who, in turn, has an increased risk of mortality. Well-nourished mothers who gain appropriate amounts of weight during pregnancy generally give birth to heavier, healthier babies.

The most important factor contributing to the infant mortality rate is a low birth weight - less than 2500 g. Infant deaths and illnesses increase sharply as birth weight declines. LBW infants are at increased risk for developmental handicaps, birth defects, respiratory and other infectious diseases, behaviour problems, and complications of medical interventions.

Medical, social, behavioural, and dietary factors before and during pregnancy contribute to the risk for LBW. Dietary factors include an inadequate intake of calories or essential nutrients such as protein, vitamins, and minerals. The more these risk factors are present, the greater the risk to mother and child.

Pregnancy and Lactation

Normal pregnancy is accompanied by anatomical and physiologic changes that are necessary to promote fetal growth and development and prepare the mother for labor, birth, and lactation.

During both pregnancy and lactation, hormonal changes affect the utilization of nutrients. They include an increase in cardiac output, heart rate, and basal metabolic rate. Preparation of the mammary glands for lactation begins during pregnancy. Lactation is initiated and maintained by hormonal changes that occur in response to the infant's sucking stimulus.

During pregnancy, body weight, lean body tissue, and fat increase. After childbirth, blood volume and extracellular fluids return to prepregnant levels.

Infants

Immediately after birth, weight is lost, but birth weight is usually regained by the 10th day. After this time, weight increases at a rapid but decelerating rate. Most infants double their birth weight by the age of 4 months and triple it within a year.

Children and Adolescents

The very rapid rate of growth in infancy is followed by slower growth during the preschool and early school-age years. Children become leaner between 6 months and 6 years, after which a gradual increase in fat thickness occurs in both males and females untilpuberty; females have a relatively greater body fat content than males at all stages of development.

Nutritional Needs of Pregnant and Lactating Women

Extra energy and nutrients are needed to support the growth of maternal tissues, and the increased metabolic demands of pregnancy as well as the growth of the fetus and placenta. During lactation, the energy and nutrients provided in the milk, and those required for its production, must be replaced.

Maternal pregnancy weight and weight gained during pregnancy are important determinants of infant birth weight. Inadequate weight gain during pregnancy and low prepregnancy weight combined with low weight gain are associated with lower than average infant birth weight and greater risks for fetal or neonatal death and neonatal disease.

The RDA for vitamins and minerals for pregnant or lactating women include levels above those for nonpregnant women (See RDA Tables). In healthy women with normal pregnancies, vitamin and mineral needs can usually be met by consuming an adequate diet. Supplements, although usually recommended, are not always associated with measurable health improvements in this population.

The need for iron is increased during pregnancy, and the National Research Council recommends an iron supplement of 30 to 60 mg per day to prevent depletion of iron stores during pregnancy and lactation. Pregnant women should be evaluated periodically to determine their level of iron stores and should receive supplements when iron stores are low.

The RDA for zinc includes a 5 mg per day increment during pregnancy over the 15 mg per day recommended for nonpregnant women. The rate of fetal malformations and other poor outcomes of pregnancy may be higher in populations where zinc deficiency has been recognized.

Adolescent Pregnancy

Maternal age influences fetal and infant mortality rates and birth weight. Mothers 15 years of age or younger have increased rates of pregnancy-induced hypertension and premature delivery, are more likely to deliver infants of low body weight, and have higher rates of fetal loss and infant mortality. While nutrition is by no means the only issue in caring for the pregnant adolescent, it is a controllable risk factor that can be reduced by programs that provide support, prenatal care, and extra food.

Disorders During Pregnancy

Pica:
Pica, a persistent compulsion to eat unsuitable substances of little or no nutritional value, is a recognized complication of pregnancy. Inadequate absorption of iron is the hazard most commonly attributed to pica.

Hypertension:
Hypertensive conditions induced by pregnancy are known as preeclampsia and eclampsia. Preeclampsia is characterized by a rise in blood pressure, generalized edema that may cause sudden, large weight gain from retained water, and loss of protein. Eclampsia is the most severe form of the disorder, characterized by convulsions that may lead to coma. Hypertension existing before pregnancy may also adversely affect pregnancy.

Diabetes:
Infants born to women with diabetes are at greatly increased risk for prematurity, congenital defects, excessively high birth weight, and other conditions that increase overall mortality, especially when the mother's blood glucose levels remain high during pregnancy.

Diabetes screening is indicated for pregnant women with risk factors for overt diabetes; a previous history of gestational diabetes, a large-for-gestational-age infant, excess amniotic fluid during pregnancy, excretion of sugar in urine, an increase of thirst and urination, or recurrent vaginal or urinary tract infections. Diabetes screening can identify diabetes in mothers who may not have been diagnosed previously and who might benefit from preventive services.

Nutritional Needs of the Fetus

Glucose and amino acids, rather than fatty acids, are the primary metabolic fuels for the fetus. Fetal energy requirements increase during pregnancy to a maximum estimated 150 kcal per day. These are modest values when compared with the mother's estimated energy requirement of 2000 to 2800 kcal per day.

A fetus near term requires about 6 to 8 g of protein per day. Most of this comes as small amounts of essential and nonessential amino acids received continuously from the placental circulation. Another source of protein occurs in amniotic fluid the fetus swallows.

Vitamin requirements of the human fetus have not been established. Although specific vitamin deficiencies have been shown to induce reproductive loss and developmental defects in experimental animals, similar data for human fetuses are not available.

Mineral requirements of the fetus, estimated from studies on fetal body composition, seem to be higher during the last few weeks of pregnancy than at any other time during prenatal or postnatal development. Little is known, however, about the specific needs for individual minerals.

Excessive alcohol consumption adversely affects fetal development. Infants born to women who were chronic alcoholics exhibit specific abnormalities of the eyes, nose, heart, and central nervous system; irritability and hyperactivity after birth as a result of alcohol withdrawal; and impaired physical and mental development despite nutritional rehabilitation. Evenone or two drinks per day are associated with higher rates of spontaneous abortion, premature detachment of the placenta, and LBW infants.

Nutritional Needs of Normal Infants

The nutritional requirements of normal infants have been investigated and RDA's have been established. Infants require three to four times greater amounts of energy per kilogram of body weight (90 to 120 kcal per day) than do adults to support their relatively high metabolic rate and needs for growth. Energy requirements of individual infants are determined by body size and composition, rates of physical growth, and activity patterns. Normal infants appear to adjust intake to needs, provided the mother is sensitive to cues of satiation; loss of interest in food, releasing the nipple from the mouth, or turning the head from the nipple or pushing the bottle or cup away.

Protein requirements are also proportionately greater in infants than in adults. Dietary protein must be sufficient to support increases in body protein. These needs can be met by protein intakes of about 2.2 g per kg for the first 6 months and 2.0 g per kg for months 7 to 12.

Because dietary fat is a concentrated source of the calories needed to meet infants' high energy needs, infants should consume 34 to 54 percent of total calories from fat. Carbohydrate should supply 30 to 60 percent of the total daily energy intake in infancy.

Although infant requirements for micronutrients are not as well defined as those for energy and protein, RDA's have been established for many vitamins and minerals. Infants fed a commercially available formula that is properly prepared should receive an adequate intake of vitamins.

Iron deficiency is the most common nutrient deficiency in infancy. Current recommendations are that infants begin consuming iron-fortified cereals at 4 to 6 months of age to prevent anaemia. Because human milk is low in fluoride and because enamel development in permanent teeth is significant during the first year of life, a fluoride supplement may be desirable for children who do not have access to adequately fluoridated drinking water.

Human milk is the food of choice for infants. It provides appropriate amounts of energy and nutrients, it contains factors that provide protection against infection, and it rarely causes allergic responses. Fat provides about 50 percent of the calories in human milk, most in the form of triglyceride, with the fatty acid pattern reflecting the maternal diet. Linoleic acid provides an average of 4 percent of the calories in human milk. The cholesterol content varies considerably but averages 20 mg per 100 ml. Lactose (milk sugar) is the major carbohydrate.

The concentrations of water-soluble vitamins in human milk generally reflect the maternal dietary intake and nutritional status. Providing folate supplementation to a women deficient inthis vitamin increases milk folate levels. Vitamin B12 deficiency has been reported in breast-fed infants whose mothers are strict vegetarians. Breast-fed infants require supplemental vitamin K at birth (human milk is low in vitamin K) and may require vitamin D supplementation if exposure to the sun is inadequate.

Infant Formulas:
The Food and Drug administration specifies the nutrient composition of commercial infant formulas. Manufacturers modify cow milk by replacing its fats with vegetable oils that are well absorbed, diluting it to a more appropriate concentration of minerals and other solutes, heating it to improve protein digestibility, and adding vitamins and minerals. Soy-based substitutes are available for infants who develop allergic or other sensitivities to substances in cow milk-based formulas.

When properly prepared, commercial formulas support normal growth and development. Errors in preparation, however, result in medical problems. Inadequately diluted formula increases the concentrations of calories, proteins and solutes and can increase levels of sodium and other substances in the blood, resulting in disturbances of acid-base balance and toxic symptoms. Overdiluting the formula reduces the level of sodium and other salts in the blood, thereby causing adverse reactions and does not provide adequate energy and nutrients for growth.

Imitation Milks:
Substitute or imitation milks, inadequate in calories and nutrients, are not suitable for feeding to infants. Malnutrition has been observed in infants fed imitation milk and in those fed nondairy creamer.

Cows Milk:
Unmodified whole cow milk is inappropriate to feed to young infants. Its lipids are less digestible than the lipids of human milk or most vegetable oils, and its concentrations of minerals and other solutes nearly exceed the excretory capacity of the immature kidney.

For infants, 2-percent and nonfat milks are deficient in energy, essential fatty acids, and certain vitamins, and they contain excessive protein and minerals per calorie provided. They are not recommended during the first year of life.

Goats Milk:
Goats milk should not be used during infancy because it is low in iron, folate, and vitamins B, C, and D. And it has a solute concentration even higher than in cow milk.

Solid Foods:
By the age of 4 to 6 months, infants have usually matured enough to sit and to control movements of the head, tongue, lips, and jaw. They can indicate when they do not want to eat. At this point feeding pureed solid foods becomes appropriate. The recommended routine is to introduce single-ingredient foods to the diet, one at a time, at weekly intervals. Iron supplemented cereals are usually the first foods added. If properly preparedand stored, pureed foods made at home are nutritionally equivalent to those prepared commercially. By the age of 1 year, foods should provide more than 50 percent of the energy intake of infants. Salt need not be added to food prepared for normal infants, and sugar should be used sparingly, or not at all. Infants should not be fed hot dogs, nuts, grapes, popcorn, uncooked carrots, round candies, and similar foods that can cause choking.

Low Birth Weight Infants

Infants born prematurely or after intrauterine growth retardation are at high risk for malnutrition and may require special feeding. Before 26 weeks of gestation, the fetus's gastrointestinal system is too immature to digest proteins, fats, or lactose. Fully competent digestive processes do not develop until about 36 weeks of gestation. Infants born prior to 34 weeks of gestation may not be able to suck effectively. The challenge is to provide adequate calories and nutrients in a form that the immature digestive and excretory systems can handle and that does not cause complications.

Providing 95 to 160 kcal and about 3 g of protein per kg per day, 4 percent of calories as linoleic acid, 40 to 50 percent of calories as carbohydrate, and sufficient water to compensate for the unusually high losses from the skin helps achieve adequate nutrition for LBW infants.

Human milk and formulas designed for full-term infants contain insufficient calcium and phosphorus to meet the needs of LBW infants and must be supplemented to permit adequate bone growth and mineralization. Because iron supplements increase susceptibility to vitamin E deficiency, recommendations for iron supplementation in the LBW infant are cautious. Preventing bone disease in LBW infants depends not only on adequate calcium and phosphorus, but also on an intake of at least 500 IU of vitamin D per day. Vitamin E requirements may be higher for LBW infants than for term infants. The recommendations for folate in LBW is 50 ?g per 100 kcal. This vitamin must be added separately to liquid multivitamin preparations because of its instability.

Methods for meeting nutritional goals for LBW infants usually include a combination of human milk; other special supplements, formulas or products fed by mouth or tube (enteral nutrition); or intravenous feeding (parenteral nutrition). Some LBW infants can be nourished adequately on their mother's milk, whereas others thrive better when provided with additional supplements. Special formulas for LBW infants contain more protein, calcium, and phosphorus than formulas for term infants. Although the composition of these formulas vary, all can support growth.

Role of Dietary Factors in Child Health

The energy requirements of children are determined by their individual basal metabolic rates, rates of growth, and activity patterns. Therefore, appropriate intakes for children of the same age, sex, and size vary.

Children need protein for the maintenance of body tissues, changes in body composition, and synthesis of new muscles. During growth, the protein content of the body increases from about 15 percent at one year to 18 percent by four years, which is also the value for adults. The RDA for protein decreases from 1.8 g per kg per day at one year to 0.8 g per kg per day at 18 years.

Inadequate intakes of vitamins and minerals will be reflected in slow growth rates, inadequate mineralization of bones, and very low reserves of micronutrients. With the relatively low prevalence of clinical signs of vitamin and mineral deficiency in the general population of children, there is no evidence that supplementation is necessary for this group. Although vitamin and mineral supplements increase the quantity of these nutrients in the diet, they have not been shown to improve biochemical indices of nutrient status in children who are already well nourished. For this reason, recommendations for vitamin and mineral supplements target children at high risk, those from socioeconomically deprived families, and those who have poor appetites or eating habits.

Preschool children are a nutritionally vulnerable group. Their growth rate is slower than it was in infancy and their nutritional needs in relation to body size proportionately reduced. Thus, they often want and eat relatively little food. Food intake can be reduced even further by the increasing independence (expressed as refusals to eat) and immature feeding skills that are characteristic of very young children.

Parents continue to be the main influence on the food intake of school-aged children, although an increasing proportion of the diet is consumed in schools, day care centres, and fast food restaurants. Between the ages of 4 and 6, children increase the varieties of foods they are willing to eat. Snacks become an important source of calories and nutrients, and may contribute as much as one-third of calories and fat, one-fifth of the protein, and nearly one-half of the carbohydrate 10-year-old children consume. These patterns emphasize the need for parents and schools to provide appropriate meals and snacks and guidance in food choices.

Role of Dietary Factors in Adolescent Health

Energy and nutrient requirements are directly related to the stage and rate of growth, and demands are greatest during the peak velocity of growth. For most nutrients the RDA's are similar to those for adults.

The RDA for calcium, 1200 mg per day, is higher for adolescents than for adults and is designed to meet the needs of the adolescent who is growing at the fastest rate. Achieving maximum bone mass during the teens and twenties can reduce the risk of developing osteoporosis later in life. The higher RDA for iron for adolescent males is also related to rapid growth, which is accompanied by increases in blood volume, muscle mass, and iron-containing enzymes. Vitamin requirements are correlated withgrowth demands rather than age.

The growth surge of adolescence demands significant increases in calories and nutrient intake to support the rapid growth rate and increased body size. In early adolescence, children still depend on their parents for food, but by the end of adolescence they are largely independent.

Irregular eating patterns are common in adolescence, reflecting this growing independence from the family and the teenager's increasingly busy social life and athletic, academic, and vocational activities. Breakfast or lunch are often skipped or eaten on the run. Snacking is characteristic of this age group and contributes significantly to nutrient intake. These snack foods are often higher in calories, fat and sugar, and lower in vitamins, minerals, and fibre, than foods consumed at family meals. Because lifetime dietary patterns are established during these years, adolescents should be encouraged to choose nutritious foods, to develop good eating habits, and to maintain appropriate levels of physical activity.

Role of Dietary Factors in Childhood Chronic Disease

Several chronic diseases have special implications in the nutrition of infants, children, and adolescents. Childhood hyperactivity (or attention deficit disorders) and eating disorders such as anorexia nervosa and bulimia occur at this age. Children with chronic disease and other handicapping conditions frequently require therapeutic diets accompanied by intensive nutrition counselling and support.

Coronary Heart Disease

The relationship between diet in infancy, childhood, and adolescence and the development of adult atherosclerosis and coronary heart disease is of great current interest. Cholesterol-lowering diets for children with elevated blood cholesterol levels, as well as for those with normal levels, have been recommended to prevent the onset of the adult disease. These recommendations are that all children older than two years adopt a diet that reduces dietary fat intake to 30 percent or less of calories, saturated fat to less than 10 percent of calories, and daily cholesterol intake to 250 mg or less.

Increasing evidence suggests that atherosclerosis begins in childhood. Cholesterol concentrations rise after infants begin to be fed, infants fed human milk or cow milk have higher blood cholesterol levels at age 6 months than do those fed formulas containing vegetable oils, but these differences are reduced once cholesterol-containing foods are added to the diet. By the age of one year, blood cholesterol levels correlate with dietary intake of saturated fat and cholesterol, they rise rapidly during the first two years of life. Childhood blood cholesterol levels have a strong genetic component, and children whose parents have high levels are two or three times more likely to have high blood cholesterol levels than children of parents with low or normal levels.

Measurements of heart disease risk factors such as high blood pressure or obesity are highly correlated with those made in the same children at age seven. Thus, pediatricians have been urged to identify and to treat children with elevated blood cholesterol levels.

Obesity

The increased rate of pediatric obesity is an important public health issue. Childhood obesity can lead to adult obesity and all its complications.

Both genetic and environmental factors are involved, there is a strong correlation of body weights to the weight of the biologic parents. Lower than normal activity levels are also related to childhood obesity. One study observed a direct relationship between the body weight and number of hours spent watching television [Dietz, W.H., and Gortmaker, S.L.: Do we fatten our children at the television set Obesity and television viewing in children and adolescents. Pediatrics 75:807-12, 1985.] .

Cognitive Performance

Animal and human studies have shown that severe malnutrition during fetal growth and early infancy retards brain cell division and alters nerve myelination (structure of nerve fibres).

Data from population groups in which malnutrition is endemic indicate a relationship between growth retardation of infants and young children and low performance in mental development tests. Children with protein-energy malnutrition in infancy who were tested at ages 5 to 11 years had poorer academic performance than children who were well nourished in infancy, which is reflected in classroom behaviour problems such as lack of attention, poor memory, poor motivation, and easy distractibility.

Studies of the effects of omitting breakfast on cognitive performance show that nutrition benefits learning. Well-nourished children aged 9 to 10 who skipped breakfast displayed higher rates of inaccurate responses to problem solving.

Inborn Errors of Metabolism

Early identification and nutrition intervention can prevent subsequent mental retardation in infants born with many kinds of metabolic disorders. Such children require long-term dietary management. One example of such a disorder is phenylketonuria.

Phenylketonuria results in excessive and potentially toxic blood levels of the amino acid phenylalanine. The goals of therapy are to provide adequate intakes of energy and nutrients but only enough phenylalanine to maintain normal growth and development. Meeting these goals requires special formulas and food productswith reduced phenylalanine content, as well as considerable support from health professionals.

Current recommendations are to continue the phenylalanine-restricted diet throughout the reproductive years, because experience with its discontinuation at ages ranging from 4 to 10 years indicates progressively decreasing cognitive functioning, learning difficulties, poor attention span, and behavioural difficulties. Evidence suggests also that phenylalanine restriction during pregnancy improves the outcome for women with phenylketonuria and their infants.

Implications for Public Health Policy

Assessment of nutritional status is an integral part of maternity care at the beginning of pregnancy and periodically throughout pregnancy and lactation to provide continuing monitoring and recommend appropriate intervention.

Evidence related to the role of diet in maternal and child health indicates that well-nourished mothers produce healthier children. Intake of sufficient energy and nutrients to attain optimal nutritional status, including appropriate weight before pregnancy and adequate weight gain during pregnancy, improves infant birth weight and reduces infant mortality. Avoiding potentially toxic substances such as alcohol or drugs during pregnancy improves birth weight and health.

Evidence related to the role of diet in infancy indicates that breast milk is the optimal food for infants. Whenever possible and as early as possible, health professionals should provide guidance and support to pregnant women and new mothers on the importance of breastfeeding and on methods for its initiation and maintenance.

Consuming the appropriate amount and form of energy and nutrients for developmental age is important for good health, as is early education about lifelong dietary patterns that help prevent disease. Parents should guide their children in developing positive eating behaviours and on age-appropriate food patterns that meet nutritional requirements but avoid excessive intake of fat, sodium, and sugar.

Physicians, nurses, and other health professionals caring for children and women of childbearing age should receive education and training in nutrition assessment, nutrition intervention for prevention of disease, and promotion of maternal and child health.

Nutrition Programs and Services

Nutrition Services:
Evidence related to the role of nutrition in maternal, infant, and child health suggests that all health care programs for these groups should provide nutrition services, especially to those people at special health or economic risk. Such services includenutrition assessment, dietary counselling, nutrition education, and referral.

Food Products:
Evidence related to the role of dietary factors in maternal and child health suggests that food manufacturers should develop nutritious, low-fat, low-salt, low-sugar snack food products for children and adolescents. Quality and safety of infant formulas and other infant foods require continued monitoring to prevent untoward health consequences. [The Surgeon General's Report on Nutrition & Health, 1988.]

Discuss It!

wilfred mututa muthengi said:

LETS ALL TAKE ACTION TOWARDS HEALTHY LIVING.

WILFRED MUTUTA MUTHENGI,KENYATTA UNIVERSITY(DEPT. OF PUBLIC HEALTH AND COMMUNITY RESOURCE MANAGEMENT) said:

WE NEED TO INITIATE GLOBAL CAMPAIGN ON POSITIVE HUMAN HEALTH.

IAN PACKINGTON said:

One way to reduce poor antenatal growth and development is to prevent maternal ingestion of fluoride, whether from drinking water or from dental products, or e.g. in drugs and environmentally dispersed and eventually ingested pesticides that can release fluoride ions internally. The fluoride ion is a potent poison and anti-nutrient. It clearly exacerbates fetal growth restriction and fetal deaths when present in the water supply used by a mother-to-be. Do not let dental health fanatics continue to dictate an agenda of fluoride promotion that is nothing more nor less than a dangerous pretence that fluorides are "quite safe and dentally very effective" in "small,regular doses" lifelong. Perhaps the worst consequences this can have for lifelong health is when the conditions for fetal growth restriction are established very early on in gestation, usually via inadequate trophoblast invasion of the uterine tissues, leading to impaired placental function. Fluoride ions exacerbate the sequence of events that must then lead inexorably to fetal growth restriction and impaired fetal development. This 'deficient fetal programming' has lifelong health implications. Even if inadequate implantation cannot yet be prevented, the exacerbating effects of fluoride certainly ought to be removed afap.

FLOW said:

Good nutrition is key to a healthy spiritual life of a christian. dont just feed on anything but feed on what should be for your bodys sake.