BSHH 314 - Unit 1 Energy Balance Equation BSHH 314 - Energy - PDF document

BSHH 314 - Energy Metabolism BSHH 314 - Unit 1 Energy Balance Equation BSHH 314 - Energy Metabolism Counting Calories • Diets and counting calories o World Health Organization o USDA o Department of Health and Human Services o Institutes of Health o CDC • First law of thermodynamics o Conservation of energy o What comes in = what’s used + what leaves 1

BSHH 314 - Energy Metabolism Counting Calories (continued) • Allegedly an insight into the plague of obesity • In fact, almost completely unhelpful in its simple form • In this course, the simple form is unpacked BSHH 314 - Energy Metabolism Energy Balance Equation • Calories in = calories out • What’s a calorie? o A measure of energy o 1 calorie  Raises the temperature of 1 gram of water  By 1° C (one degree Celsius) o 1 kilocalorie (1 kcal) = 1000 calories  1 kilogram of water by 1° C o Confusingly, calorie counts are in kcals • An alternative system uses joules as the measure of energy 2

BSHH 314 - Energy Metabolism Calories in = Calories out • What’s measured is potential chemical energy o The potential that a chemical has to release energy o The potential chemical energy of the food coming in o Is a promise to body that it can turn  Food chemicals  Into biochemicals  The body can turn into actual energy • “Calories in” measures fuel value of food • “Calories out” measures the fuel value of biochemicals from food • Fuel in = fuel used BSHH 314 - Energy Metabolism Fuel In = Fuel Used • What’s “in” and what’s “out” o “In” is what the body takes in o “Out” is what the body uses o “Out” includes potential energy that remains fuel o “Out” is also what leaves the energy cycle  For other purposes in the body  Or is removed as waste • Fuel in = Energy consumed + Fuel stored + Non-fuel use + Waste 3

BSHH 314 - Energy Metabolism Example, Fuel In = Fuel Used • Fuel in = Energy consumed + Fuel stored + Fuel converted + Waste • Fuel in: a bowl of chicken noodle soup o Chicken: protein and fat o Noodles: carbohydrates • Fuel used o Energy consumed: heart beat o Fuel stored: body fat o Fuel converted: enzymes o Waste: excreted in urine BSHH 314 - Energy Metabolism Fuel In = Fuel Used • What does “=“ represent? • Digestion o From outside the body o To inside the body • Unit 2 - Food to Fuel 4

BSHH 314 - Energy Metabolism Fuel In • Food • Macronutrients o Carbohydrates o Protein o Fats • Other caloric constituents o Alcohol o Polyols  Artificial sweeteners such as mannitol and sorbitol o Fiber o Organic acids  Such as acetic acid (vinegar) and lactic acid (milk) BSHH 314 - Energy Metabolism Fuel In (continued) • Potential energy in food (counting calories) • Macronutrients o Carbohydrates = 4 calories per gram o Protein = 4 calories per gram o Fat = 9 calories per gram • An example, chicken noodle soup o Carbohydrate: 17.3g x 4 cal/g = 69.2 calories o Protein: 7.4g x 4 cal/g = 29.6 calories o Fat: 5.6g x 9 cal/g = 50.4 calories o Total: 149.2 calories 5

BSHH 314 - Energy Metabolism Fuel In (continued) • Adjustments to energy value of food o Digestive waste o Food preparation o Micronutrients deficiencies o Energy used to convert food to fuel o Timing of eating o Manipulation of eating • Fuel in = Food energy ± Food preparation - Waste - Energy use - Deficiencies ± Timing ± Manipulation BSHH 314 - Energy Metabolism Fuel In (continued) • Digestive waste o State of digestion  For example, gall bladder and fat digestion o Reaction of digestive system  For example, allergic reaction to protein impairs digestion • Food preparation o For example, cooking  Predigests food  Denature proteins (allergens) 6

BSHH 314 - Energy Metabolism Fuel In (continued) • Energy used to convert food to fuel o Digestion breaks down molecules o From least to most energy required  Fat  lipids (fatty acids)  Carbohydrates  glucose and other sugars  Protein  amino acids o The body uses energy to  Convert macronutrient to constituent  Transport constituent into blood stream • Conventionally accounted for as fuel used • Should be deducted from the caloric value of the food BSHH 314 - Energy Metabolism Fuel In (continued) • Micronutrient deficiencies o Nutrient rich food versus empty calories o Micronutrients for digestion, assimilation, and use o For example, B vitamins essential for energy metabolism 7

BSHH 314 - Energy Metabolism Fuel In (continued) • Timing of eating o Circadian rhythms o Body uses fuel differently through day, month, year o Affects  Appetite  Digestion  Energy metabolism BSHH 314 - Energy Metabolism Fuel In (continued) • Manipulation of eating o Eating for more than hunger  For example, comfort foods o Food manufactured to promoted “conditioned hypereating”  The End of Overeating by David Kessler o Social significance of food and eating  For example, ritual fasting 8

BSHH 314 - Energy Metabolism Fuel Used • Fuels have entered the blood stream o Glucose (blood sugar) o Amino acids o Lipids (fatty acids) • Taken immediately to liver • Then to location of need • Unit 3 - Fuel to Energy: Conversion Processes BSHH 314 - Energy Metabolism Fuel Used (continued) • Regulated by hormones o Insulin o Stress hormones (adrenal glands)  Adrenaline  Cortisol o Thyroid • Unit 4 - Fuel to Energy: Hormonal Regulation 9

BSHH 314 - Energy Metabolism Fuel Used (continued) • What happens to the three fuels • Fuel in = Energy consumed + Fuel stored + Non-fuel use + Waste o Energy consumed  Converted to energy used by cells  Unit 5 - Fuel to Energy: Cell Metabolism o Fuel stored  Converted to a stored potential chemical energy  Unit 3 - Fuel to Energy: Conversion Processes o Non-fuel use  Converted or used directly for purposes other than energy  Unit 3 - Fuel to Energy: Conversion Processes BSHH 314 - Energy Metabolism Fuel Used (continued) • Fuel in = Energy consumed + Fuel stored + Non-fuel use + Waste (continued) o Waste  Converted or eliminated as not usable by the body  Unit 3 - Fuel to Energy: Conversion Processes 10

BSHH 314 - Energy Metabolism Energy Consumed • Convert fuel to energy by cells o Three processes  Resting metabolism  Work  Non-exercise activity BSHH 314 - Energy Metabolism Energy Consumed (continued) • Resting metabolism o Also basal metabolism  RMR or BMR o Energy consumed for basic metabolic functions such as  Breathing and heartbeat  Body temperature  Cellular processes  Thinking • Unit 7 - Resting Metabolism 11

BSHH 314 - Energy Metabolism Energy Consumed (continued) • Resting metabolism (continued) o What affects energy consumed by resting metabolism  Fitness of skeletal muscle  Cardiorespiratory fitness  Age  Stress  Thyroid function  Infection and inflammation  Sex hormone imbalance o Environmental conditions that affect fitness, aging, stress, thyroid, immunity, and sex hormones BSHH 314 - Energy Metabolism Energy Consumed (continued) • Work o Also exercise, physical activity, or thermic effect of activity o Energy consumed by skeletal muscle to do things such as  Walk, run, climb  Lift weights  Gardening • Unit 6 - Physical Activity and Exercise 12

BSHH 314 - Energy Metabolism Energy Consumed (continued) • Work (continued) o What affects energy consumed by skeletal muscle  Fitness of skeletal muscle  Cardiorespiratory fitness  Stress  Age  Infection and inflammation  Sex hormone imbalance o Environmental conditions that affect fitness, aging, stress, immunity, and sex hormones BSHH 314 - Energy Metabolism Energy Consumed (continued) • Non-exercise activity o Also spontaneous physical activity o Energy consumed by skeletal muscle for involuntary actions such as  Shivering  Fidgeting  Startle response • Unit 7 - Resting Metabolism 13

BSHH 314 - Energy Metabolism Energy Consumed (continued) • Non-exercise activity (continued) o What affects energy consumed by non-exercise activity  Fitness of skeletal muscle  Cardiorespiratory fitness  Age  Stress  Thyroid function  Infection and inflammation  Sex hormone imbalance o Environmental conditions that affect fitness, aging, stress, thyroid, immunity, and sex hormones BSHH 314 - Energy Metabolism Fuel Stored • Stored in two basic forms o Glycogen is stored glucose o Adipose tissue (body fat) is stored fatty acids o Most glucose converted to lipids (fatty acids) and stored as body fat • 80% to 90% of fuel is stored • Unit 3 - Fuel to Energy: Conversion Process 14

BSHH 314 - Energy Metabolism Fuel Stored (continued) • What affects fuel storage o Energy demands  Resting metabolism  Work  Non-exercise activity o Hypothalamus  Metabolic set point  Affects – Thyroid – Stress hormones – Appetite and nervous system – Digestive hormones BSHH 314 - Energy Metabolism Non-fuel Use • Amino acids  proteins o Enzymes o Muscle o Cell membranes • Glucose o Stress hormones o Collagen • Lipids o Cell membranes o Hormones o Breast milk 15