Flashcards in 11) Fat, Carbohydrate, Water, Mineral, Electrolyte, and Vitamin Requirements in Infancy, Childhood, and Adolescence Deck (133)
What must the energy balance during childhood and adolescence balance?
- Energy expenditure
- A level of physical activity that is consistent with good health
- Must include energy associated with tissue deposition
The energy requirements for growth are (low/high) in comparison to maintenance.
The energy requirements for growth are low in comparison to maintenance, apart from which period? Why?
The first few months of life, in which growth is substantial
What are the two components for the energy needs for growth? (2)
1) Energy used to synthesize growing tissues
2) Energy deposited in those tissues
The energy cost of growth in children is largely derived from which children?
Pre-term infants and children recovering from malnutrition
In practicality, when is the energy cost of growth particularly an issue in infancy?
Only during the first half of infancy, in which energy deposition contributes significantly to energy requirements
What equation is used to predict the TEE for individuals aged 0 to 2 years old? How does it vary between boys and girls?
- EER = TEE + Energy Deposition
- It does not vary between sexes
The number of calories required for energy deposition (decreases/increases) as infancy progresses.
How is the energy content of tissue deposition computed?
From rates of protein and fat deposition
Why isn't the PAL included in the calculation to determine the EER of individuals aged 0 to 2 years old?
Because there is very little physical activity
What allows for the determination of whether a child is acquiring a sufficient quantity of calories?
How does the determination of energy status compare between growth velocity and growth charts?
- Growth velocity is a sensitive indicator of energy status
- Indicates whether growth faltering is occurring earlier than growth charts
What does weight velocity indicate? What does length velocity indicate?
- Weight velocity indicates acute episodes of dietary intake
- Length velocity indicates chronic factors
When are nutrient requirements on a per-weight basis highest in the life cycle? Why?
- During the first six months of life
- Characterized by the most rapid growth rates
Pre-mature infants possess an energy requirement around __% higher than term infants.
Why do pre-mature infants possess a greater energy requirement than term infants?
1) They have a higher basal metabolic rate
2) They have a lower coefficient of absorption of fats and carbohydrates
On a per-kilogram basis, energy expenditure is two times (smaller/greater) in infants than in adults.
What are the primary organs contributing to the infant's basal metabolism?
What does the transition from an intrauterine to an extrauterine environment alter in the infant?
Causes an increase in oxygen consumption in the infant
Why do infants have a proportionally high BMR for their size?
Increased oxygen consumption of vital organs in proportion to their weight
How does the energy cost of growth vary throughout the first month of life?
- 35% during the first month
- 3% at 12 months
- 1% at 5 years old
What are the periods associated a greater energy cost of growth?
- Infancy (0 to 2 months)
- Adolescent growth spurt
What does the exposure of a newborn to mild cold result in? What does the exposure of a newborn to even lower temperature result in?
- Non-shivering thermogenesis (cold)
- Shivering thermogenesis (colder)
What is the most important contribution to non-shivering thermogenesis?
An increase in fatty acid oxidation in BAT
How does the quantity of BAT vary between infants and adults?
Infants possess a greater quantity of BAT than adults
How does the function of WAT compare to BAT?
- WAT is primarily used as a site for energy storage
- BAT is used to burn fat to produce heat and regulate body temperature
What are structural characteristics of BAT that contribute to its function? (4)
- Highly vascularized
- Innervated by the CNS
- Multilocular (multiple lipid droplets)
- Greater proportion of mitochondria
What structure is responsible for the production of energy dissipated as heat in BAT?
- UCP1 is responsible for the uncoupling of oxidative respiration from ATP production
- Increases proton leakage across the inner membrane of the mitochondria of BAT
Where is UCP1 contained? What is it activated by?
- Contained in the mitochondria
- Activated by free fatty acids and the sympathetic nervous system