Chap 6: Weight management

Question 1

What is BMI? What is considered as healthy weight according to BMI?

Answer 1

The ratio between weight and height
BMI = weight (kg)/height (m2

Question 2

What are the 2 waist circumferences?

Answer 2

Apple shape: more weight above waist

Pear shape: more weight below the waist

Question 3

What is waist-to-hip ratio?

Answer 3

• Waist measurement at the smallest point of the natural waist; hip measurement at the widest part of the hips
• Can be a good predictor of mortality in older people
• Takes into account differences in body structure

Question 4

Differentiate between essential fat and storage fat.

Answer 4

Essential fat
- Helps with physiological function (e.g., nerve conduction)
- Stored in small amounts in organs and muscles

Storage fat
- Helps keep us warm by insulating our bodies
- Higher body fat in women due to size of bones, muscle mass, fat fluctuation during menstruation, pregnancy, and menopause

Question 5

What are the measurements we can use to assess body fat?

Answer 5

Skinfold fat measurement
- A caliper is used to measure the amount of skinfold on various sites

Bioelectrical Impedance Analysis (BIA)
- Low-level electric current is passed through the body and the opposition to the flow of current is measured

Dual-energy X-ray absorptiometry (DXA)
- X-rays quantify the skeletal and soft-tissue components of body mass.

Hydrostatic (underwater) Weighing
- Measures weight of the displaced fluid

Air Displacement Plethysmography
- Total body volume is measured by air displacement

Question 6

Differentiate between EMR and RMR.

Answer 6

Resting Metabolic Rate (RMR): largest component of our daily energy budget
- 90% of daily caloric expenditure

Exercise Metabolic Rate (EMR): comes from all types of daily physical activities
- 10% of energy expenditure

Question 7

What is the impact on body if overweight?

Answer 7

1. Type -2 diabetes
2. Heart disease and stroke
3. Cancer
4. Premature death
5. Cognitive problems like dementia

Question 8

What are the 3 ranges of obesity?

Answer 8

Extreme obesity (BMI of 40+)
- medical treatment can be performed Gastric bypass surgery, laparoscopic gastric banding, gastric bubble

Moderate obesity (BMI of 30–39)
- 6-month trial of lifestyle therapy, including a supervised diet and exercise

Overweight (BMI of 25–29)
- Cut back moderately on food intake, focus on developing healthy eating and exercise habits

Question 9

Explain the income effect and substitution effect.

Answer 9

Income effect: option of purchasing and consuming things of value
- Purchasing food has increased, which has resulted in higher caloric intakes

Substitution effect: consumption of readily available foods, most of which are high in fat and low in quality