Transcript Neonatal Growth and Nutrition


Promotion of normal growth rate, organ
development, and body composition

Prevention of later disease
— Obesity
— Cardiac
— Allergic
— Cancer

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
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

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”

Vary considerably among children
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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

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
(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
 The
DRIs are largely extrapolated
from infant or adult data
 Exceptions
are for energy, protein
and iron where balance studies have
been performed
(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

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

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
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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
GIRLS
2 - 18 yrs

Obesity (continued)
— Young children will not innately choose a wellbalanced 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
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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

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
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Vary significantly based on gender and age

DRIs for males
— 13 - 15 years old: 2000 Kcal/d
— 16 - 18 years old: 3200 Kcal/d
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DRIs for females*
— 13 - 15 years old:
— 16 - 18 years old:
*add
2200 Kcal/d
2100 Kcal/d
300 Kcal for pregnancy; 450 Kcal for lactation

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
Nutrient
Gender
Increment
Increment
(average)
(peak of growth spurt)
Suggested
Calcium
M
F
210
110
400
240
1100
1200*
Iron
M
F
0.57
0.23
1.1
0.9
10
13**
Zinc
M
F
0.27
0.18
0.50
0.31
12
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

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

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
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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