Energy requirement calculation ***

Question 1

What are the key elements of the Total Energy Expenditure (TEE) in healthy subjects?

Answer 1

• Resting Energy Expenditure (REE): About 60% of TEE.
• Activity induced Energy Expenditure (AEE): About 30% of TEE.
• Diet induced Energy Expenditure (DIT or TEF): About 10% of TEE.

Question 2

What is the primary component of total energy expenditure comprising 60–70%?

Answer 2

Basal Metabolic Rate (BMR).

Question 3

What is a product of mainly the metabolism of lean body mass and is therefore dependent on variables related to it, such as body weight, height, sex, and age?

Answer 3

Resting Energy Expenditure (REE) or Basal Energy Expenditure (BEE).

Question 4

What is the energy required to thermoregulate and respond to changes in the environmental temperature, that comprises 10–15% of total energy expenditure?

Answer 4

Adaptive thermogenesis.

Question 5

What percentage of the TEE is comprised by the diet induced thermogenesis (DIT)?

Answer 5

10–15%

Question 6

What is the most variable component of total energy expenditure, and accounts for 15- 50% of TEE?

Answer 6

Activity induced energy expenditure.

Question 7

What is considered the gold standard to measure caloric needs?

Answer 7

The calculation of heat production from chemical processes.

Question 8

Which type of calorimetry involves measuring energy expenditure through the measurement of the production or loss of heat by the use of a ventilation hood and a respiration chamber to continuously measure VO2 and VCO2?

Answer 8

Direct calorimetry.

Question 9

Which type of calorimetry involves the measurement of heat production by measuring O2 consumption and/or production of CO2 (both in mL/min)?

Answer 9

Indirect calorimetry.

Question 10

What is the respiratory quotient used for?

Answer 10

To evaluate substrate utilization.

Question 11

What are the different parameters of the respiratory quotient?

Answer 11

• Normal: 0.7-1.0.
• ≥1.0: May indicate excessive CO2, lipogenesis, and overfeeding.
• ≤0.7: May be due to metabolic or technical causes.

Question 12

What are the most famous prediction equations for the calculation of TEE?

Answer 12

The Harris-Benedict, Ireton-Jones and Mifflin-St Jeor formulas.

Question 13

When is the rule-of-thumb used for the calculation of TEE?

Answer 13

If the usage of indirect calorimetry is impossible, or the use of predictive equation is not feasible.

Question 14

What is the rule-of-thumb?

Answer 14

• 20-25 kcal/kg of weight for overweight patients.
• 30 kcal/kg of weight for patients with normal weight.

Question 15

What components are the principal source of energy in a normal diet (particularly during anaerobic exercise), and comprise 40–55% of energy requirements in the Western diet?

Answer 15

Carbohydrates

Question 16

What components represent the major form of energy storage in the body, with high content of energy and low hydration?

Answer 16

Dietary lipids.

Question 17

How much energy do dietary lipids contain?

Answer 17

1 g of triglyceride carries 9.3 kcal.

Question 18

What are the three types of dietary fatty acids?

Answer 18

• Saturated
• Monounsaturated
• Polyunsaturated

Question 19

What are the three types of aminoacids?

Answer 19

• Non-essential amino acids.
• Conditionally essential amino acids.
• Essential amino acids.

Question 20

What is an example of a conditionally essential amino acid?

Answer 20

Glutamine, which may become essential in certain disease states if the requirement for particular amino acids is increased.

Question 21

What are the recommendations for carbs, fat and protein regarding their involvement in the TEE?

Answer 21

• Carbs (CHOs): 40-55% of total energy, 50% of TEE, less than 10% from sugar.
• Fat: 25-35% of total energy, 30% of TEE, less than 10% from saturated fatty acids.
• Protein: 15-20% of the total energy, 20% of TEE.

Question 22

What’s the energy content of carbs, protein and fat?

Answer 22

• 1 g carb = 4 kcal
• 1 g prot = 4 kcal
• 1 g fat = 9 kcal

Question 23

What are the four methods of calculating the energy requirements?

Answer 23

• Direct calorimetry.
• Indirect calorimetry.
• Prediction equations.
• Rule of thumb.

Question 24

What is the Harris-Benedict equation for men?

Answer 24

BMR = 88.362 + (13.397 ⨯ weight in kg) + (4.799 ⨯ height in cm) - (5.677 ⨯ age in years)

Question 25

What is the Harris-Benedict equation for women?

Answer 25

BMR = 447.593 + (9.247 ⨯ weight in kg) + (3.098 ⨯ height in cm) - (4.330 ⨯ age in years)

Question 26

Which prediction equation created in the 1990s provided a valid estimate of RMR?

Answer 26

The Mifflin-St Jeor formula.

Question 27

Which prediction equation revised by Roza and Shizigal in 1984 provided a valid estimate of BMR?

Answer 27

The Harris-Benedict equiation.

Question 28

What is the Mifflin-St Jeor formula for men?

Answer 28

RMR = (10 ⨯ weight in kg) + (6.25 ⨯ height in cm) - (5 ⨯ age in years) + 5

Question 29

What is the Mifflin-St Jeor formula for women?

Answer 29

RMR = (10 ⨯ weight in kg) + (6.25 ⨯ height in cm) - (5 ⨯ age in years) - 161