Energy and Body Balance - Exam 2

Weight management is related to …..

calories in vs calories out

Negative energy balance

calories consumed < expended; leads to weight loss

Positive energy balance

calories consumed> expended; leads to weight gain

Things that affect food intake

availability, serving size, energy density, cooking skills, living environment

Things that affect energy expenditure

metabolism, physical activity, energy efficiency

Energy balance is … and …

complex and variable

The body will … and … change in our weight

adapt, resist

The 3 ways calories/energy are expended

basal metabolic rate(BMR), physical activity, thermic effect of food (TEF)

Total energy expenditure

sum of calorie expenditure

Basal Metabolic Rate (BMR)

energy metabolism that occurs after waking up until 12 hours after the last meal

BMR includes energy functions that

sustain life such as breathing, heart beat, brain, kidneys, liver

Examples of things that can affect BMR

body mass, age, growth, stress, etc.

Components of Total energy expenditure

physical activity, thermic effect of food (TEF)

Physical activity

energy expenditure through voluntary physical effort, including daily activities, exercise or physical labor

Resting energy expenditure (REE)

calories burned while sitting or sleeping; less restrictive

What makes up most of the calories burned in a day

the resting energy expenditure

Energy needed for muscle contraction

15-30%

Exercise related thermogenesis (EAT)

structured/planned activity

Non-exercise activity thermogenesis(NEAT)

unstructured (posture, daily activities)

Thermic effect of food

the process of burning calories as you digest, absorb, transport, store, and metabolize food.

Body burns …. of calories consumed from meal

5-10%

Body Mass Index (BMI)

measure of weight relative to height often used to diagnose overweight/obesity

Standard formula to calculate BMI

weight in kg/(height in meters)2

BMI and disease risk

cardiovascular disease, diabetes, stroke, hypertension, gall bladder disease, etc.

Overweight BMI

25-29.5

Obesity BMI

over 30

Underweight BMI

Healthy weight BMI

18.5-24.9

Negative effects of being underweight BMI

decreased energy, respiratory complications, heart irregularities, infertility, delayed wound healing, weakened immune system, osteoporosis

Limitations of BMI

does not distinguish between fat and muscle mass : athletes(less body fat

Osteoporosis

decreased bone mass and density that can result in increased risk of fractures

Body composition

total body mass/body weight

Categories of body fat

essential fat and storage fat

Essential fat

fat necessary for normal physiological functioning

Storage fat

fat in adipose tissue, tissue under the skin, and fat that pads the essential organs

Percent of body fat differs with

age and body needs

Gynoid pattern

pear shaped; fat over muscle and under skin at hips and thighs; subcutaneous fat

Android pattern

apple shaped; body fat can be stored under abdominal muscle around the internal organs; visceral fat; associated with …

Visceral fat

stored around the organs; contributes to heart disease and diabetes

Subcutaneous

stored under the skin; temperature regulation

Waist circumference

35 in or greater in women/ 40in+ in men can lead to an increased risk in visceral fat risks/health conditions

Factors of obesity (3)

energetics, environment, genetics

Energetics

obesity is caused by a positive energy balance as a result of eating more calories than ya burn

Environmental factors of obesity

access to a grocery store, society, biking versus walking, social network (ppl you spend time with), and healthy affordable food is hard to purchase in some areas.

Set point theory

the body will adjust based on if you're gaining or losing weight to maintain a particular weight

Hunger

the physiological need to eat

Hunger may be triggered by

low blood glucose and low glycogen

Appetite

the desire to eat

The appetite is triggered by

the sight/smell of food.

Short term regulators of hunger

neuropeptide Y, ghrelin, and leptin

Neuropeptide Y

neurotransmitter that increases food intake and blood glucose levels promoting the storage of energy in fat cells and diminishes energy expenditure.

Ghrelin

hunger stimulating hormone when the STOMACH IS EMPTY

Leptin

hormone released by fat cells to signal the brain that the body has had enough to eat, signals to reduce food intake & increase energy metabolism

High levels of leptin leads to

decreased food intake, increased energy metabolism, long term weight control

Long term regulators of hunger

Leptin

Why don’t diets work

unrealistic to follow long term, good/bad foods

What works for weight loss/management

promote small moderate lifestyle changes to reduce energy in and increase energy burned: decrease portion size, increase physical activity.

Treating Childhood Obesity

must proceed with caution

What is the problem with calorie deficits with children

it can inhibit growth during rapid development phases

General Recommendations for Childhood obesity

weight maintenance, gain height and then grow into their weight

The best weight loss regimens

promote small moderate lifestyle changes, reduce energy in and increase energy out

The proposed focus on quality diet

a balanced diet integrating all food groups is encouraged to promote long term weight management; consume more fruits, vegetables, low-fat dairy products, protein from lean meats and vegetable source, unsaturated fats instead of saturated fats

Drug therapy is often used as a …

component of weight loss

Drug therapy for weight loss is recommended when

person is extremely obese & life threatening health complications exist

Cons of drug therapy for weight loss

it is not a permanent solution, it is ineffective without diet, physical activity, and behavior mods