Nutritional Requirements During Pregnancy

1
Nutritional Requirements During Pregnancy

• Related to
• Perinatal Nutrition
• Maternal Developmental Stage
• Fetal Growth and Development
• Growth of Maternal Supporting Tissues
• Expansion of Maternal Blood Volume

2
Impact of Perinatal Nutrition on Fetal
Development
3
Change in Requirements of Selected Nutrients
During Pregnancy

• Most of increased need occurs in 2nd and 3rd
  trimesters
• Nutrient requirements are increased
  disproportionately to energy requirements
• Reserves are particularly important during 1st
  trimester or when intakes may not be consistent
• Larger increases in requirements may be needed
  for adolescents or undernourished women

4
Protein and Energy Requirements

• Protein
• Expansion of maternal blood volume
• Growth of breast and uterine tissues
• Growth of fetal tissues
• Increase from 0.8 g/kg body weight to 1.1
  g/kg
• 10 g/day

• Energy
• Sustains metabolic activity
• Supports protein synthesis
• Reflects fat and carbohydrate intakes after
  increased protein requirement is included
• Total cost 55,000 kcal
• 28 wks x 7 d
• 300 kcal/day

5
Equivalents of 300 kcal Energy and 10 g Protein
1 oz meat 8 g1 svg dairy 7 g1 svg grain 2
g
48 g protein360 kcal
7 g protein 90 kcal
2 g protein 245 kcal
30 g protein 310 kcal
6
Roles for Increased Maternal Nutrient
Requirements - 1 of 2

• Cell replication
• DNA synthesis
• Zinc, Folate ( B12), iron
• Protein synthesis
• Protein B6
• Fetal skeletal development
• Mineral formation
• Calcium phosphorus
• Calcium metabolism
• Vitamin D magnesium
• Matrix formation
• iron, copper, vitamin C, vitamin A, vitamin K,
  protein

7
Roles for Increased Maternal Nutrient
Requirements- 2 of 2

• Energy metabolism
• Electron transport
• Iron, copper
• ATP synthesis utilization
• Magnesium, thiamin, riboflavin, niacin
• Oxygen transport
• Hemoglobin synthesis
• Iron, copper, B6
• Erythropoiesis
• Folate ( B12), iron
• Cell replication nutrients

8
Nutritional Requirements For Lactation

• Related to
• Biosynthesis of Human Milk
• Human Milk Nutrient Composition
• Infant Developmental Needs

9
Nutrient Requirements for Lactation
10
Energy Cost of Lactation
Milk Volume Produced 750 mL/day 600
mL/day (6-12 mos) Energy Content 75 kcal/100 mL
562 kcal/day 450
kcal/day Energy Intake Equivalent 562/85
661 kcal/day 450/85 529
kcal/day Recommended allowance 500 kcal/day
Energy Deficit of 150 kcal/day x 7 1050
kcal/week 0.3 lb body fat (3500 kcal/lb fat
)
11
Effect of Maternal Diet Composition on Nutrient
Content of Human Milk
12
Human Milk Fat Composition

• Omega-6 Fatty Acids
• Types
• Linoleic acid (182)
• Arachidonic acid (204)
• Functional Roles
• Eicosanoid synthesis
• Satisfy essential fatty acid requirements
• Sources
• Vegetable seed oils (LA)
• Meat (AA)

• Omega 3 Fatty Acids
• Types
• Linolenic acid (183)
• Eicosapentanoic acid (205)
• Docosahexanoic acid (226)
• Functional Roles
• Eicosanoid synthesis
• Nerve retina activity
• Sources
• Flaxseed, nuts, soybean (LNA)
• Fish (EPA/DHA)
• Alga (DHA)

13
Infant Nutritional Requirements

• Related to
• High Growth Velocity
• Neurological Development
• Vulnerability to Dehydration
• Developmental Immaturity
• Digestive tract
• Renal function

14
Average Weight and HeightBirth to 36 months
15
Energy Requirements By AgeLight to Moderate
Activity
Average for males and females
16
Protein Requirements by Age
Average for males and females
17
Primary Roles of Nutrients During Infancy 0-12
Months

• Brain/nervous system development
• Structural Components
• Long chain PUFA, B12, vitamin E, galactose
• Cognitive development
• Iron
• DHA

• Growth
• Cell replication
• DNA protein synthesis
• Skeletal development
• Mineral matrix formation
• Calcium metabolism
• Maintenance of Fluid Balance
• High metabolic rate
• High surface area/volume ratio

Requirement not established
18
Relative Size of Body Water Compartments Infants
and Adults
Percentage of Body Weight
19
Developmental Factors Affecting Infant Nutrition

• Digestive Tract
• Low lipase levels and bile salt concentration
• Low disaccharidase activity except lactase
• Low saliva production
• Low pancreatic amylase activity
• Small stomach volume (10-20 mL)
• Low gastric acidity
• Renal System
• Low urine concentrating capacity (700 mOsm/L)
• Immune system
• Intestinal epithelium permeable to macromolecules

20
Reconciling Developmental Barriers to Infant
Feeding
21
Comparison of Human Milk to Cows Milk and Soy
Formulas
Unique to human milk
22
Weights of Bottle-Fed vs Breast-Fed Infants
Birth to 9 Months
23
Preterm and SGA Infants High Nutritional Risk

• Physiologically immature
• Metabolic abnormalities
• Fluid and electrolyte imbalances, acidosishypo-
  or hyperglycemia
• Illness present
• Respiratory distress, sepsis, pneumonia,
  meningitis
• Poor nutrient stores
• Fat, glycogen, micronutrients
• High nutrient requirements
• Intravenous (parenteral) feeding often necessary

Small for gestational age
24
Solid Food Introduction

• Nutritional Indicators
• Insufficient nutrient density of milk to
  meet increasing needs

• Physiological Indicators
• Intestinal epithelial cell closure
• prevents entry of whole proteins
• Digestive enzyme maturation
• Functioning at adult levels
• Presence of disaccharidases
• Saliva, gastric acid levels increase
• Bile concentration increases
• Urine concentrating ability increased
• Deciduous teeth erupt
• Extrusion reflex disappears

Milk 1 kcal/g Cereals 2 kcal/g Meat 2-3
kcal/g
25
Childhood Nutritional Requirements

• Related to
• Linear growth and weight gain
• Cognitive development
• Exposure to childhood diseases

26
Childhood Nutrient Requirements

• Linear growth
• Cell replication
• Skeletal formation and development
• Brain development
• C20 and C22 fatty acids, B12, vitamin E
• Cognitive development
• Iron
• Immune function
• Iron, vitamin A, vitamin C, protein, zinc, B6
• Cell replication

27
Average Weight Gain Girls and Boys 1-11 years
28
Nutrition and Brain Development

• Brain growth
• EFA are limiting nutrients
• LA3 kcal and LNA 0.5 kcal
• Brain and nerve structure
• Vitamin B12 in myelinization
• 60 lipid composition
• Neural membrane function
• C22 in synaptic membranes (signal transduction)
• C20 in Ca transport (signal activation
  reception)
• C20 C22 incorporated selectively

29
Nutritional Risks in Childhood
30
Change in Percentage of Overweight Children Ages
6-11 (1963-1995)
Above the 95th percentile using 1960 norms-
Source CDCP
31
Adolescent Nutrition (11-18 yrs)

• Related to
• Rapid linear growth
• Addition of 45 of adult skeletal mass
• 20 of adult height and 50 adult weight
• Sexual maturation
• Changes in body composition

32
Energy Requirements During Adolescence
33
Protein Requirements by Age
34
Average Weight Gain Girls and Boys 11-17 years
35
Adolescent Nutrient Requirements

• Linear Growth
• Cell replication
• Skeletal mass and density
• Sexual maturation
• Gender differences in body composition
• Gender differences in reproductive development

36
Body Composition Changesin Girls and Boys Ages 8
to 18
37
Nutritional Risks of Adolescents
38
Change in Percentage of Overweight Adolescents
Age 11-17 (1963-1995)
Above the 95th percentile using 1960 norms-
Source CDCP
39
Adult Nutritional Requirements18-51 years

• Related to
• Cessation of linear growth
• Increasing sedentary lifestyle
• Establishment of chronic disease risk factors
• Adjustment to chronic stress

40
Nutrition Risks of Adults

• Macronutrient excesses and micronutrient
  deficiencies
• Diminished activity and high fat intake
• Stress-related effects on immune function

41
Relationship of Disease Risk Factors to Nutrient
Intakes
42
Mean Change in Weight by Age U.S. Adults
(1971-75 to 1984)
43
Adult Nutritional Requirements51 yrs and older

• Related to
• Physical, emotional, and physiological changes
  affecting appetite and ability to eat
• Medications that may interact with nutrients
• Diseases with specific nutritional requirements

44
Percentage of Malnutrition in Long-term Health
Facilities

• Contributing Factors
• Sensory losses
• Sarcopenia
• Decline in digestive/absorptive efficiency
• Stress
• Disease
• Medications

45
Age-Related Changes in Nutrient Requirements
46
Comparison of AdultNutrient Requirements