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Childhood: Nutritional Goals. Promotion of normal growth rate, organ development, and body composition Prevention of later disease Obesity Cardiac Allergic Cancer. Childhood: Growth. Birth weight triples by 1 year, but does not quadruple until age 2
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Childhood: Nutritional Goals • Promotion of normal growth rate, organ development, and body composition • Prevention of later disease • Obesity • Cardiac • Allergic • Cancer
Childhood: Growth • Birth weight triples by 1 year, but does not quadruple until age 2 • Birth length increases by 50% in year 1, but does not double until age 4 • After age 2, children average 2 -3 kg and 6 - 8 cm of growth per year
Serve as a guide for estimating nutrient need • DRIs recently revised for specific childhood ages (Institute of Medicine) • Much of the data are extrapolated from adult, but increasingly more specific • Since they are group recommendations, they include a margin of safety Childhood: DRIs
Childhood: Malnutrition The Two Factors Which Contribute to Childhood Malnutrition POVERTY IGNORANCE
Children after the age of 1 are largely unprotected because • Programs are much less specific regarding nutrient requirements compared with < 1 year • A child’s diet and an adult diet are similar; thus, children can be shortchanged in a general assistance paradigm Childhood: Poverty and Malnutrition
Willful or unwitting ignorance by parents may contribute to nutritional imbalances: • Parent allowing child to choose foods leading to unbalanced diet • Parent willfully manipulating diet without consideration for balance and nutrient needs • Imposition of adult diet on young child • Fad foods/”nutriceuticals” Childhood: Ignorance and Malnutrition
Vary considerably among children • Dependent on: • Basal metabolic rate • The Barker Hypothesis & Fetal “Programming” • Growth rate • Physical activity • Body size • Range from 1000 Kcal/d at 1 year to 2200 Kcal/d at 12 years Childhood: Energy Requirements
Absorption of amino acids increases protein synthesis in children (unlike adults) • The body is unable to store excess dietary amino acids • Uses them for energy production if energy intake is low • Or converts them to glucose or fat if energy intake is adequate Childhood: Protein Requirements
(Continued) • Daily protein requirement ranges from 12 grams at 1 year to 35 grams at 12 years • Note that protein requirements during childhood are low compared to newborn or teen • Growth rates are slower • Tissue synthetic rates are slower • Amino acid needs for growth decrease from 56% of total intake at birth to 5% at 5 years Childhood: Protein Requirements
The DRIs are largely extrapolated from infant or adult data • Exceptions are for energy, protein and iron where balance studies have been performed Childhood: Minerals/Elements
(Continued) • Minerals/elements that are likely to be low in the diet of young children • Calcium • Crucial for preteen girls re: future osteopenia • Iron • Zinc • Magnesium Childhood: Minerals/Elements
Healthy, growing children consuming a varied diet do not need vitamin supplementation • Children at nutritional risk who may benefit from vitamin supplementation • Those from deprived, neglectful or abusive families • Those consuming fad diets • Those with chronic disease, particularly affecting the GI tract • Those on dietary programs for managing obesity • Those on vegetarian diets without adequate dairy products Childhood: Vitamins
Childhood: Nutritional Problems - Worldwide • Protein, energy and protein-energy malnutrition • Endemic areas include sub-Saharan Africa • Iron deficiency • World-wide for various reasons • Intestinal blood loss (parasitic) in developing countries • Inadequate intake (cow’s milk) in developed countries • Vitamin A deficiency
Obesity • Begins generally after the age of 2 - do not restrict dietary fat before this age • 30% of children are obese: rate is increasing • Childhood obesity is not generally “outgrown” • Growth adiposity rebound between 5 and 7 years is critical in predicting adult obesity • Early rebound more predictive of later obesity Childhood: Nutritional Problems - USA
Height and Weight Curves GIRLS 2 - 18 yrs
Obesity (continued) • Young children will not innately choose a well- balanced diet unless appropriate foods are presented and models of food acceptance given • Parents and school lunch programs must provide nutritious foods at regular meals and snacks, and allow the children to decide how much they eat • Children do best 4-6 times a day with relatively low volume foods • Snacks should be considered normal meals Childhood: Nutritional Problems - USA
Obesity(continued) • The influence of advertising should not be underestimated • 50% of television advertising is for foods (higher in children’s programs) • Most foods shown on TV are high in fat, sugar and salt (e.g., sweetened cereal, fast foods, snack products, candy) • TV messages have primarily emotional/psychological appeal • Physical inactivity likely plays the largest role in childhood obesity Childhood: Nutritional Problems - USA
Iron Deficiency: 6-13% • Children at risk due to low iron stores at birth (up to 250,000 per year) • Growth-retarded infants • Infants of diabetic mothers • Children at risk due to inadequate intake • Early introduction of cow’s milk (before 12 months) • Unsupplemented infant formula (up to 30% of sales) • Breastfeeding without iron supplementation (20% at 9 months • Children with increased GI blood loss Childhood: Nutritional Problems - USA
Adolescence: Energy Requirements • Vary significantly based on gender and age • DRIs for males • 13 - 15 years old: 2000 Kcal/d • 16 - 18 years old: 3200 Kcal/d • DRIs for females* • 13 - 15 years old: 2200 Kcal/d • 16 - 18 years old: 2100 Kcal/d *add 300 Kcal for pregnancy; 450 Kcal for lactation
Adolescence: Protein Requirements • Second peak of protein accretion during childhood • Associated with significant growth spurt • DRIs for males • 11 - 14 years (pre-growth spurt): 45 g/d • 15 - 18 years (growth spurt): 59 g/d
Daily Increments in Body Content and DRIs of Selected Nutrients in Adolescents Nutrient Gender Increment Increment Suggested (average) (peak of growth spurt) Calcium M 210 400 1100 F 110 240 1200* Iron M 0.57 1.1 10 F 0.23 0.9 13** Zinc M 0.27 0.50 12 F 0.18 0.31 9 All values are mg/d * to increase bone mineral stores * increased iron turnover due to menses
Onset of puberty in both sexes increases: • Energy needs for increased physical activity • Protein needs for rapid skeletal growth • Calcium needs for bone mineralization • Onset of menstruation in girls increases: • Iron demand to replace blood loss and match expanding blood volume • Calcium need to protect against later osteopenia Adolescence: Factors Influencing Nutritional Needs
Low energy intake (dieting) creates difficulties in obtaining adequate levels of micronutrients • Replacement of milk (or other high-calcium foods) with soft drinks, coffee, etc., results in a low calcium intake associated with a high protein intake — leads to negative calcium balance and increased risk of osteoporosis • High iron requirements to sustain rapidly expanding blood volume and lean body mass and to offset menstrual losses in females are frequently not met; iron deficiency is particularly prevalent in female athletes Adolescence: Nutritional Problems
Positive zinc balance is essential for adolescent growth; zinc deficiency is characterized by growth failure, hypogonadism, decreased taste acuity; increased prevalence in Middle East • Vegetarian diets without eggs and milk lead to vitamin D and B12, riboflavin, protein, calcium, iron and zinc deficiency; adolescents on vegan diets must learn to assess protein quality and balance • Obesity, often carried over from preteen years, becomes worse with poor quality snacks, limited food choice and frequent eating away from home Adolescence: Nutritional Problems
Summary • Nutritional issues in childhood and adolescence differ in developing and developed countries • The antecedents of adult diseases are found in childhood nutritional disorders • Obesity • Allergy • ?Cancer