Energy Balance and Health

Question 1

What is energy balance?

Answer 1

• Balance between how much energy is consumed (energy intake) and how much energy is expended (energy expenditure)
• State of energy balance: individuals who maintain their body weight over a sustained period

Question 2

What is energy imbalance?

• positive
• negative

Answer 2

• Positive energy balance
  
  • Energy consumed > energy expended
  • Results in weight gain
• Negative energy balance
  
  • Energy consumed < energy expended
  • Results in weight loss

Question 3

Describe obesity:

Answer 3

• Defined as excess accumulation of body energy, in the form of fat (adipose tissue).
• Excess energy in subcutaneous store, saturation causes stores in visceral abdominal tissue, and in organs like pancreas, heart(ectopic fat deposition)
• Visceral adipose tissue accumulation is a major risk factor for cardiometabolic disease, whereas subcutaneous fat seems to be neutral or protective.

Question 4

What knock on effects can obesity cause?

Is obesity income dependent?

Answer 4

• hypertension
• cancer
• heart, liver disease
• T2DM
• Mood, Reproductive disorders
• Obesity is not dependent on income, even low income countries suffer with obesity

Question 5

Describe the use of BMI:

How can ethnicity impact BMI?

Answer 5

• Surrogate measures of body fatness
• Measures excess weight(not fat) - proxy measure
  BMI = weight(kg)/height(m2)

Lower BMI cut-off points for Asian populations: due to ethnic differences in the relationship between BMI and health (e.g., differences in body fat distribution)

Question 6

What are some advantages of using BMI?

Answer 6

• Simple, inexpensive and non-invasive tool
• High BMI is an important risk factor for CVD and T2D
• Good tool for tracking and identifying population trends - comparisons across time, countries, population subgroups

Question 7

What are some disadvantages of using BMI?

Answer 7

• Surrogate measure of body fatness
• Age, sex, ethnicity, and muscle mass can influence interpretation
  e.g.: older people with the same BMI as a young person, would carry more body fat
• Does not distinguish between excess fat, muscle or bone mass
• Does not provide indication of body fat distribution. Fat around abdominal are at higher risk of CVD

Question 8

What are some of the other criteria, alongside high BMI an obese person must have in order to be clinically diagnosed?

Answer 8

• must have central obesity(waist circumference + ethnicity specific values)
  –> raised triglycerides
  –> reduced HDL cholesterol
  –> raised blood pressure
  –> raised fasting plasma glucose

Question 9

What are some factors which contribute to obesity?

Answer 9

• Societal influences, individual psychology, activity, environment, biology, food production, food consumption

Question 10

what percentage of the population eat out at least once a week

Answer 10

27% of the population eat out at least once a week

Question 11

Provide examples of:
G1 - unprocessed/minimally processed food
G2 - processed culinary ingredients
G3 - processed foods
G4 - ultra-processed foods

Answer 11

• fresh fruit and veg, grains, meat. fish. eggs
• plant oils, butter, cream, honey, salt
• canned veg, meat or fruit, wine, beer, cheese
• pop, chicken nuggets, ice-cream, ping meals

Question 12

Describe the issues associated with ultra-processed food in society:

What effect can these cause on obesity?

Answer 12

• Formulations mostly of cheap industrial sources of dietary energy and nutrients plus additives, using a series of processes’’ and contain minimal whole foods.
• May facilitate overeating and onset of obesity (typically high in calories, salt, sugar, and fat)
• May be engineered to have supernormal appetitive properties, may lead to excessive eating behaviour.
• Observational evidence suggest that ultra-processed food intake is a risk factor for obesity, poorer cardiometabolic health and all-cause mortality.