Ch 9 Energy Balance and Healthy Body Weight

Why is body weight important for health?

Being underweight or overweight both present risks to health and life.

What is body composition?

The proportion of adipose tissue (body fat) to lean tissue.

What makes up body composition?

Muscle, bone, fat, and other tissues that make up total body weight.

Why are underweight individuals at higher risk during emergencies?

They are more likely to die during famine or siege.

What are hospital-related risks for underweight people?

Increased health risks, especially if NPO (nothing by mouth) for tests/surgeries.

What are condition increase death risk in underweight individuals?

Surgical complications and wasting diseases (unintentional weight loss)

What is a major cause of death risk in cancer patients related to weight?

Starvation

What diseases are linked to excess body fat?

Arteries, heart disease, stroke, diabetes, cancers (breast, colon, endometrium), kidney disease, non-alcoholic fatty liver disease

What do adipose tissues release?

Adipokines(hormones that regulate inflammation and metabolism)

What happens in obesity related to inflammation?

A shift in adipokines increases inflammation and insulin resistance.

How does weigh loss help?

Reduces inflammation and improves health

How is obesity classified?

A chronic disease (adiposity-based chronic disease)

What are obesity-related conditions?

Abdominal hernias, pregnancy/surgery complications, flat feet, gallbladder disease, gout, hypertension (HTN), medication dosing errors, reproductive disorders, sleep apnea, varicose veins, increased accident rates

Why does fat distribution matter?

It influences risk of obesity-related diseases

What is central obesity?

Excess fat around the trunk/abdomen

What is visceral fat?

Fat surrounding organs in the abdominal cavity

Why is visceral fat dangerous?

Higher risk of disease that subcutaneous fat

What is metabolic syndrome?

Combination of central obesity, diabetes/prediabetes, high blood glucose (insulin resistance), high blood pressure (HTV), altered blood lipids

What does metabolic syndrome increase risk factor?

Heart disease

Who is more prone to central obesity?

men of all ages, woman after menopause

What lifestyle factor is linked to abdominal obesity?

High alcohol intake

What correlates with leaness?

High physical activity

What happens as BMI (Body Mass Index) increases?

Health risks increase

What BMI indicates urgent need for weight loss?

BMI>30

What BMI range requires treatment if no other risk factors?

25-29.9 (focus on preventing weight gain).

What waist circumference increases risk?

>35 inches (women), >40 inches (men)

What diseases are linked to obesity risk?

Cardiovascular disease (CVD), impaired glucose tolerance, hyperthyroidism, high LDL

What is energy balance?

Relationship between energy intake (food) and energy expenditure.

What happens if you eat more that needed?

Weight gain

What happens if you eat less than you need?

Weight loss

What determines how many calories you need?

Gender, physical activity, and genetics

What is basal metabolism (BMR)?

Energy used for basic body functions (breathing, circulation, temperature).

What are voluntary activates?

Intentional movements like walking, sitting, running.

What is the thermic effect of food?

Energy used to digest food (increases metabolism after eating)

What are EERs(Energy Efficiency Ratio)?

Dietary Reference Intakes estimated energy needs

What factors affect BMR?

Age (decreases with age), Height/weight (higher=higher BMR), Growth (higher during growth), Lean body mass (more lean mass= higher BMR), gender (females have lower BMR than males)

How do thyroid hormones affect metabolism?

Higher thyroxine means higher BMR

How does fever affect BMR?

Increases BMR

How do stress and environment affects BMR?

Stress increases BMR; climate adjustments also affect it.

How does malnutrition affect BMR?

Lowers BMR

How does physical activity affect BMR?

Increases BMR

What is a healthy BMR range?

18.5-25

Why is BMI not accurate for athletes?

It doesn’t account for muscle mass

What is the ideal body composition?

Balanced fat and lean mass-not just weight

What body fat % is healthy?

males 18-21%, females 23-26%

How can central obesity be measured?

Waist circumference

What is a skinfold test?

Measures body fat using calipers.

What is a DEXA scan?

Imaging method to measure fat distribution

What is hunger?

Physiological need for food

What hormone increase hunger?

Ghrelin

What is appetite?

Desire to eat influenced by environmental and emotions

What reduces appetite?

Medications, disease states

What environmental factors affect eating?

Social situations

What influences food choices?

Personal preferences

What is satiety?

Feeling of fullness after eating

How long does satiety last

About 4-6 hours during the day, 12-18 hours overnight

What is leptin?

Hormone from fat that suppresses appetite.

Which macronutrients affect satiety?

Protein, carbs, and fat

Which macronutrient has greatest satiety effect?

Protein

What foods help satiety?

Carbs with soluble fiber.

What is set point theory?

Body maintains a certain weight.

What is role of microbiota?

May influence obesity

Does genetics guarantee obesity?

No, but strongly influences it

What triggers overeating?

Food environment

What lifestyle factors increase obesity?

Low activity, poor access to healthy foods

What happens in negative energy balance

Glycogen breaks down, fat used for energy

What happens in fasting/low carb?

Glycogen depleted, protein used, ketones formed

Are fasting/cleanses needed?

No

What happens in positive energy balance?

Carbs→ glycogen/fat, protein → fat, fat stored

What does alcohol do?

Adds empty calories and promotes fat storage

What is key for weight loss?

Portion control

What should you do when eating out?

Read menu, take leftovers home.

Meal frequency recommendation?

3 meals or smaller frequent meals

What foods should be eaten?

Lower calorie density foods.

What should be limited?

Sweets and alcohol

What is meal prep benefit?

Portion control

What is first step in weight loss?

Set realistic goals.

Do small reductions help with weight loss?

Yes, even modest loss improves health

Are fad (fast result) diets effective?

No most fad diets are unsustainable and can lead to nutritional deficiencies.

BMI>30 calorie reduction?

Up to 1000 kcal/day

BMI 25-35 reduction?

500-750 kcal/day

Typical calorie intake for weight loss?

Women: 1200-1500, Men: 1500-1800

What foods should be included in a healthy diet?

Fruits, veggies, nuts, legumes, fish, poultry, low-fat dairy, whole grains

Why is exercise important?

Maintains weight loss

How does exercise affect hunger?

Delays hunger

What does muscle do?

Burns fat

Other benefits of exercise?

Better sleep, less stress

Can you out-exercise a bad diet?

no

Warning signs of being underweight?

Fatigue, cold, BMI<18.5, missed periods

How to gain weight?

Eat nutrient-dense foods, frequent meals

When should you drink fluids?

Between meals

What type of trying helps?

Resistance training

How many extra calories for gain?

500-700/day

When are obesity medications used?

BMI> 30 or >27 with risk factors

What must obesity meds be combined with?

Diet and exercise

What is a common concern with meds?

Side effects

When is obesity surgery used?

BMI >40 or >35 with risk factors

How does surgery work?

Reduces stomach size and/or absorption

What must patients follow?

Strict diet before/after

Benefits of surgery?

reduces comorbidities (additional complications)