Energy Balance
“If we could give every individual the right amount of nourishment and exercise, not too little and not too much, we would have found the safest way to health.” Hippocrates
Review theEnergy Nutrients
Energy is measured in Kilocalories (kcal)
• Carbohydrates 4 kcal / g• Fats 9 kcal / g• Proteins 4 kcal / g
Total Caloric Intake = Total Caloric Expenditure
1800 Calories Ingested 1800 Calories Burned
(Weight is Maintained)
Energy Balance
Total Caloric Intake > Total Caloric Expenditure
2500 Calories Ingested 1800 Calories Burned
(Weight Gain)
Energy Balance
Total Caloric Intake < Total Caloric Expenditure
1800 Calories Ingested 3000 Calories Burned
(Weight Loss)
Energy Balance
All excess Calories, no matter what the original source, is eventually stored as Fat!
3500 kcal = 1 lb body weight
Energy Balance
EnergyIngestion and Expenditure
1 Bagel with Cream Cheese
Provides 330 kcal
To expend (‘burn up’) 330 kcal, you would need to brush your teeth for 2 hours and 24 minutes.
That’s enough energy to power an electric toothbrush for 37 hours and 8 minutes.
EnergyIngestion and Expenditure
1 Power Bar
Provides 240 kcal
To expend (‘burn up’) 240 kcal, you would need to pedal a bicycle at 10 mph for 5.7 miles.
That’s enough energy to power a 34 hp motorcycle going 40 mph a distance of 0.36 miles.
EnergyIngestion and Expenditure
1 Big Mac (without the Fries)
Provides 560 kcal
To expend (‘burn up’) 560 kcal, you would need to clean the house for 124 minutes.
That’s enough energy to power an electric vacuum cleaner for 138 minutes.
Represents the amount of Calories the food will produce when used or stored by the body.
Found on the Food Label
Food Energy Value
What is the food energy value of 1 slice of this bread?
Represents the amount of Calories the food will produce when used or stored by the body.
How many Calories per serving?
Food Energy Value
Food Energy Value = 50 kcalories
Foods that are higher in Caloric content per weight (measured in grams) of food.
Which cereal is more calorically dense (contains more kcalories in a ¾ cup serving)?
Calorically Dense Foods
Foods that are higher in Caloric content per weight (measured in grams) of food.
Which cereal is more calorically dense (contains more kcalories in a ¾ cup serving)?
Calorically Dense Foods
Serving Size ¾ cupCalories 249 kcal Carbs 36 g Proteins 6 g Fats 9 g
Serving Size ¾ cupCalories 116 kcal Carbs 28 g Proteins 1 g Fats 0 g
Foods that are higher in Caloric content per weight (measured in grams) of food.
Which cereal is more calorically dense (contains more kcalories in a ¾ cup serving)?
Calorically Dense Foods
Serving Size ¾ cupCalories 249 kcal Carbs 36 g Proteins 6 g Fats 9 g
Serving Size ¾ cupCalories 116 kcal Carbs 28 g Proteins 1 g Fats 0 g
What accounts for the increased Calories in the granola cereal?What do you think is the main source of calories in the frosted flakes cereal?
Affected by
• Thermic Effect of Food (TEF)
• Basal Metabolic Rate (BMR)
• Physical Activity
Determining Caloric Needs
Energy Expenditure
Thermal Effect of Food (5-10%)+
Basal Metabolic Rate (60-70%)+
Physical Activity (10-40%)=
Total Energy Expenditure (100%)
• Increased energy expenditure after a meal• Calories are burned to provide the energy needed to digest and absorb nutrients• An ingested meal of 800 calories burns 40 to 80 kcalories
Thermic Effect of FoodNah. I learned
about TEF. The more
calories I eat, the more I
burn.
Aren’t you worried about gaining weight
with all that food?
Basal Metabolic Rate
• The amount of energy required for bodily functions to sustain life at rest
• All organ functions (‘involuntary work’)
• Accounts for 60-70% of energy requirements
Energy Essential for Life Support (Involuntary Work)
• Circulation• Respiration• Temperature Maintenance• Nerve Transmission• Kidney Function• Liver Function• and other Involuntary Life Functions
Basal Metabolic Rate
BMR is also called the Resting Metabolic Rate (RMR) because it is a measurement of the energy required by resting tissue to maintain basic function.
Basal Metabolic Rate
Measuring BMR Directly
Calorimeter-rarely used due to time and expense-requires 12 hours of fasting-requires an environmentally controlled room or chamber
Basal Metabolic Rate
Measuring BMR Indirectly
• Measuring oxygen and carbon dioxide levels
• Blood work to measure thyroid function tests (the thyroid regulates basal metabolic rate)
• Estimate mathematically with formulas like the Harris-Benedict Equation
Basal Metabolic Rate
Measuring BMR with the Harris-Benedict Equation
Men BMR = 66.5 + (13.75 x kg + (5 x cm) -(6.78 x age)
WomenBMR = 655 + (9.56 x kg) + (1.85 x cm) – (4.68 x age)
Basal Metabolic Rate
Harris – Benedict Equation Example
Female, 132 lb, 5’ 4”, 36 yo132 lb = 60 kg5’ 4” = 162.5 cm
655 + (9.56 x 60) + (1.85 x 162.5) - (4.68 x 36)655 + 573.6 + 299.7 - 168.48BMR = 1360 kcalories per day (approx)
Basal Metabolic Rate
Measuring BMR with the Harris-Benedict Equation
Harris -Benedict Equation got your head spinning?
Don’t try to memorize the equation. Instead, use an Online Tool.
Basal Metabolic Rate
A Simpler Calculation to Predict BMR
Female0.9 kcal / kg body weight / hour132 lbs = 60 kg0.9 kcal x 60 kg x 24 hrs = 1296 BMR
Male1 kcal / kg body weight / hr165 lbs = 75 kg1 kcal x 75 kg x 24 hrs = 1800 BMR
Basal Metabolic Rate
Factors Affecting BMR
Body Composition
• Greatest factor affecting BMR is muscle mass
• Increased BMR in lean, muscular bodies
• Women generally have lower BMR’s than men
Basal Metabolic Rate
Factors Affecting BMR
Growth Periods
• Growth hormones stimulate cell metabolism, raising BMR
• BMR rises first 5 years, levels off, then declines with age
• BMR rises with puberty, pregnancy and lactation
Basal Metabolic Rate
Factors Affecting BMR
Temperature (Bodyand Environmental)
• Fever increases BMR 7% for every degree over 98.6o F (0.83o C)
• BMR rises in cold weather to generate more body heat
Basal Metabolic Rate
Factors Affecting BMR
Illness and Disease
• Diseases causing increased cell activity (e.g., cancer) increase BMR
• Starvation and malnutrition states decrease BMR
Basal Metabolic Rate
Factors Affecting BMR
Hormonal Status
• The thyroid regulates metabolism
• Hypothyroidism decreases BMR
• Hyperthyroidism increases BMR
Basal Metabolic Rate
• Voluntary (conscious) work done by the body
• Goes above and beyond BMR / RMR
• Categorized by activity level
Physical Activity
Physical Activity
Physical Activity Level (PAL) Categories
• Sedentary Studying, watching TV• Low Active Slow walking 30 min / day• Active Moderate Activity 60 min / day• Very Active Vigorous Activity 5-7 hrs / day
Activity ‘counts’ when the heart rate is increased
Common Diseases that Increase BMR
• Cancer
• Heart Failure
• Emphysema
• Anxiety
Meeting the Energy Needs of Ill and Hospitalized Person
Used to described the nutritional status of patients
Less than IBW More than IBW
Ideal Body Weight (IBW)
Factors Contributing to Decreased Caloric Intake During Hospitalization
• Side Effects of Medications
• NPO and Dietary Restrictions
• Stress and Anxiety
• Personal Preferences (including Ethnic)
• Physical Barriers (unable to feed self)
Meeting the Energy Needs of Ill and Hospitalized Person
Meeting the Energy Needs of Ill and Hospitalized Person
Did you eat lunch yesterday? No, I was at
Physical Therapy.
Meeting the Energy Needs of Ill and Hospitalized Person
The nurses tell me you refused supper
last night.
They lost my teeth. I couldn’t chew the
meat.
Meeting the Energy Needs of Ill and Hospitalized Person
You have to try to eat or you won’t
get better.
Can I have my breakfast now?
Meeting the Energy Needs of Ill and Hospitalized Person
Not until we take a few tests. Maybe
this afternoon.Why are they blaming ME
for not eating?
What can you do to help?
What conditions interfere with people eating adequately in the hospital?
What can the nurse do to improve dietary intakes?
Meeting the Energy Needs of Ill and Hospitalized Person
What can you do to help?
• Oral Care before and after meals
• Limit care during mealtimes
• Provide snacks when possible
• Discuss personal preferences
• Remove barriers
Meeting the Energy Needs of Ill and Hospitalized Person