Pediatric Nutrition I n Nutrition of Neonates and Infants –Prior to 1 year of age –Growth Rates and Nutritional Goals –Nutrient Requirements n Energy, Protein, Minerals, Vitamins n Absorptive/Digestive Immaturity –Human Milk –Infant Formulas

W Growth rates are most rapid in the first six months of human life W Nutrient requirements on a weight basis are highest during the first six months W Rapid organ growth and development occurs during the last trimester and first six months W The detrimental effects of nutritional insufficiencies are magnified during periods of rapid organ growth (I.e., vulnerable periods for brain growth)

W Provide sufficient macro- and micronutrient delivery to promote normal growth rate and body composition, as assessed by curves which are generated from the population W Curves exist for: –Standard anthropometrics: weight, length, OFC –Special anthropometrics: arm circumference, skinfold thickness –Body proportionality: weight/length, mid-arm circumference: head circumference ratio W Body composition measurements (e.g. DEXA, PeaPod) are not standardized yet

GIRLS Birth to 36 mo

BOYS Birth to 36 mo

W Term infants require Kcal/kg/d if breast-fed, Kcal//kg/d if formula W Differences are due to increased digestibility and absorbability of breast milk –Presence of compensatory enzymes (lipases)

(Continued) n Energy requirements are 20% higher in premature infants due to: –Higher basal metabolic rate –Lower coefficient of absorption for fat and carbohydrates n Energy requirements decrease to 75 Kcal/kg/d between 5-12 months

GrossEnergyIntakeMetabolizableEnergyIntake Basal Metabolism Thermic Effect of Feeding Activity Energy Stored “growth” Tissue Synthesis Energy Excretion

W Diseases of infancy that increase BMR (cardiac, neurologic, respiratory) affect energy requirements W Diseases that increase nutrient losses (malabsorption due to cystic fibrosis, celiac disease, short bowel syndrome) increase the need for energy delivery, although the BMR is normal

W Late gestation and infancy is the time of highest protein accretion in human life W Protein requirements range from 1.5 g/kg/d (healthy breast-fed infant) to 3.5 g/kg/d (septic, preterm infant) W Amino acid synthesis is incomplete in the premature; taurine and cysteine are additional essential amino acids because of immaturity of enzyme systems

W Preterm infants:15 g/kg/d W Toddlers: 6 g/kg/d W Adolescents: 4 g/kg/d

Nutrient Term Preterm 5-12 Month Neonate Neonate Infant Neonate Neonate Infant Na (mEq/kg/d) K (mEq/kg/d) Ca (mEq/kg/d) Iron (mEq/kg/d) Zinc (mEq/kg/d)

W Water-soluble vitamins (B, C, folate, etc.) are rarely a problem in newborns and infants; babies are born with adequate stores and/or all food sources have adequate amounts W Fat-soluble vitamins (A,E,D,K) may present significant problems because of relatively poor fat absorption by newborn infants (especially premature infants)

W K: Needs to be given at birth to prevent hemorrhagic disease of newborn; adequate thereafter due to synthesis by intestinal bacteria W D: Low amounts in breast milk; infants born in winter in north and infants who are clothed at all times (minimal sun exposure) have been identified with rickets WAAP now recommends 400 IU/d for all infants

(Continued) W A: Essential for normal structural collagen synthesis and retinal development deficiency in premature infants contribute to fibrotic chronic lung disease W E: Antioxidant that protects against peroxidation of lipid membranes; preterms have poor antioxidant defense and are subjected to large amounts of oxidant stress; vitamin E deficiency causes severe hemolytic anemia

Rapid transit time + Immature digestive capabilities Immature digestive capabilities = Reduced nutrient retention Reduced nutrient retention

W Primary sources of CHO in newborn and infant diet are disaccharides (esp. lactose) W Disaccharides must be broken into component monosaccharides to be absorbed –Lactose = glucose + galactose (lactase) –Sucrose = glucose + fructose (sucrase) –Maltose = glucose + glucose (maltase)

W Intestinal lactase concentrations are low at birth and are not inducible W Amylase, necessary for breaking down starches, are not adequate until > 4 months

Sucrase, Maltase, Isomaltase Glucose Uptake Gluco-amylase Salivary Amylase Zymogen Granules in Pancreas Pancreatic Amylase Lactose 10 Wks 20 Wks 24 Wks Wks 22 Wks

W 85 % of ingested protein is absorbed in spite of functional immaturities: –Reduces stomach acidity –Low pancreatic peptides levels (chymotrypsin caroboxypeptidases) W Compensation is by trypsin and brush border peptidases

W Adult: 95% W Term infant: 85-95% W Preterm infant: % (dependent on source of fat)

W Low levels of intestinal lipases W Small bile salt pool

W Committee on Nutrition of the AAP strongly recommends breastfeeding for infants W The rates of breastfeeding have risen recently, but the attrition rate is high

W The goal of the AAP and NIH Health People 2010 is to have 75% women breastfeed, with a continuation rate of 50% at 6 months W It is necessary to breastfeed for at least 12 weeks to achieve the immunologic and disease preventative benefits of breast milk W Physician’s role is to support, counsel and trouble-shoot (Continued)

W Health W Nutritional W Immunologic W Neurodevelopmental W Economic W Environmental

n Studies in developed countries –Reduced prevalence of: » Diarrhea » Otitis media » Lower respiratory infection » UTI » NEC (in preterms) » SIDS

W Protection of infant from chronic diseases: –Insulin dependent diabetes mellitus n (OR 0.61) –Inflammatory bowel disease –Allergic disease –Childhood lymphoma (OR 0.91) –Obesity (OR )

W Protection of mother from: –Pregnancy –Postpartum hemorrhage –Bone demineralization –Ovarian cancer

W Complete human nutrition for 6 months –Iron at 4 months –Vitamin D in northern climates, covered infants and mothers, vegetarians (vegans) W Energy is more accessible than from formula –Compensatory lipases  better fat retention –But, BF babies grow slower too

W Amino acid spectrum matches infant need; lower protein and solute load W Faster gastric emptying  less reflux

W Better visual acuity (early) — Role of DHA? W Higher IQ (debatable) — Independent of nursing — Components in human milk which may potentiate the effect: » DHA » Growth factors

W 25% reduced risk of obesity if BF — Adjusted OR: —Dose response (Koletzko et al) — Rate of Adolescent Obesity —12% if BF < 1month —2% if BF 12 months —“Small” effect compared to OR if parents are obese (4.2), low physical activity (3.5) or TV (1.5)

W Reduced cost of feeding — No formula cost (-$855/year) — Increased maternal consumption (<+$400) — Net savings of >$400/child W Reduced health care costs due to: — Lower incidence of childhood illness W Reduced income loss due to: — Less days lost to cover childhood illness

W Galactosemia in infant W Illicit drug use by mother W Certain maternal infectious diseases — Active TB — HIV (US only) — Not CMV W Certain maternal medications — Anti-neoplastics, isotopes, etc — How about SSRI's?

W Promotes adequate growth, but not brain and immunologic development compared to human milk WNew formulas contain LC-PUFAs WSoon to be added: prebiotics; probiotics W Most are cow-milk based, although soy-protein based and fully elemental formulas are available

(Continued) W Cow’s milk (not formula) is contraindicated in the first year of life — High solute load can lead to azotemia — Inadequate vitamin D and A — Milk fat poorly tolerated — Low in calcium; can lead to neonatal seizures — Gastrointestinal blood loss/sensitization to cow- milk protein

W Feed humans human milk — It is species specific W If not human milk, CMF or Soy formulas with iron are indicated W Hypoallergenic formulas are highly specialized, expensive and overused