2. Energy
2
Energy
= kilocalories
= kcal
= Calories
Unit of measure used to
express the amount of
energy produced by foods
in the form of heat
Carbohydrates – 4 kcal/g
Protein – 4 kcal/g
4. What do we need energy for?
4
-
-
Energy in food fuels body processes
Muscular activity
Growth
Tissue repair and
maintenance
Chemical processes
Body temperature
6. Basal Metabolism
6
-
-
-
Basal Metabolic Rate (BMR)
the minimum Caloric requirement to sustain life in a
resting individual
Breathing
Heartbeat
Body Temperature
Growth
Organ Functions
7. 7
Estimate Energy Used for Basal
Metabolism
Men:
- BMR Calories = body weight (lbs) x 11
Women:
- BMR Calories = body weight (lbs) x 10
Varies ± 20%
- Depending on physical activity, muscle mass,
height, health status, genetic traits
8. Factors that Effect BMR
8
Body composition - lean vs. fat tissue
Growth
Hormones
Fever
Height
Environmental temperature
Starvation, fasting, and malnutrition
Weight loss from dieting
Stress
Certain drugs
9. Thermic Effect of Food
(Dietary Thermogenesis)
9
Amount of energy required to
digest, absorb, and metabolize
food
Resting Energy Expenditure
(REE)
= BMR + Thermic Effect of
Food
10. 10
Physical Activity – Voluntary
Muscle Movements
Inactive
- sitting most of the day
- less than 2 hours of moving about slowly or
standing
Average
- sitting most of the day
- walking or standing 2-4 hours, no strenuous activity
Active
- physically active 4 or more hours each day
- little standing, some strenuous activities
11. Measuring Caloric Need
11
Indirect Calorimetry
indirect estimate of resting energy
expenditure that measures the
ratio of CO2 expired to the
amount of O2 inspired
gold standard
rarely used in clinical settings due
to time and cost
12. Estimating Total Caloric Need
12
Harris-Benedict Equation
Mifflin-St. Jeor Equation
Ireton-Jones Equation
Schofield Equations
Toronto Equation
“Rule of Thumb” = 30 kcal/ kg body weight
15. Energy in Food
15
Energy-dense foods
- provide relatively high levels of Calories
Energy-dense foods tend to be nutrient-poor
Nutrient-rich foods tend to be low in energy
US Diet tends to be high in energy-dense foods
17. Estimate Calories by Food Groups
17
Food Group
Ave. Calories / serving
Starch/grains
80
Fruits
60
Milk
skim or 1%
2%
whole
100
120
160
Nonstarchy Veggies
25
Meat and beans
Plant-based protein
Lean
Medium fat
High fat
varies
45
75
100
Fat/oils
45
Based on American Diabetes Association Exchange lists
18. Calculating Calories in Food
18
Nutrient grams x calories/gram = calories
Example:
15 g carbohydrate x 4 kcal/g = 60 Calories
10 g protein x 4 kcal/g = 40 Calories
5 g fat x 9 kcal/g = 45 Calories
Total = 145 Calories
Most foods are a mixture
19. Estimating Calories in a Recipe
19
Example: Ricotta Cheese Cookies
- 2 C sugar
774 x 2 = 1548
- 1 C butter
1628
- 15 oz. Ricotta cheese
560
- 2 tsp. vanilla extract 31 x 2 =
62
- 2 large eggs
72 x 2 =
144
- 3 ½ C flour
3.5 x 455 = 1593
- 2 tbsp. baking powder
0
- 1 tsp. salt
0
5535 / 36 =
154 Calories per Cookie
20. How Is Caloric Intake Regulated?
20
Hunger
- Physical and psychological sensations
that lead people to acquire and eat food
- Causes weakness, stomach pains,
irritability
Satiety
- Feeling of fullness or of having eaten
enough
21. How Is Caloric Intake Regulated?
21
Appetite
- The desire to eat
- A pleasant sensation aroused by
thoughts of taste and enjoyment of food
- Can override hunger and satiety mechanisms
Appetite may or may not relate to hunger
23. Weight Change
WEIGHT MAINTENANCE
23
WEIGHT GAIN
WEIGHT LOSS
CARBS
PROTEIN
BMR
IN
OUT
Dietary
Thermogenesis
FAT
CALORIE INTAKE
(WHAT YOU EAT)
Physical Activity
vs.
TOTAL ENERGY
EXPENDITURE
24. Tips for increasing activity
24
Find something you enjoy
Use the buddy system
Spread activity over the
entire day if desired
Start slowly and gradually
increase activity
Keep moving / move more
Keep an activity log
25. Calorie Requirements Homework
25
Go to http://www.bmrcalculator.org/
Do not get tempted by the pretty flashing
advertisements.
Input your information for age, gender, weight, and
height.
Discover your Calorie requirements based off of 2
estimating equations