Chapter 8 Diet in the Prevention and Treatment of Obesity

Question 0

What does energy density of food have to do with the causes of obesity? 8.2.1

Answer 0

Energy density reflects energy content of foods and is expressed as per unit weight.
Foods with low energy density provide less energy relative to the weight than foods with a higher energy density therefore a larger and more satisfying amount can be consumed
Therefore foods high in fat can lead to an overconsumption of energy.
This is referred to as passive overconsumption.

Question 1

Discuss the relationship of water content of food, energy density and energy intake and weight control. 8.2

Answer 1

energy intake - energy output = 0

positive energy imbalances due to

1. increase in energy intake with no change in output
2. decrease in energy output
3. increase in energy intake and decrease in output.

Factors contributing to increased intake are;
Energy density
portion size
soft drinks
eating out
fast food
snacking

Question 2

How does soft drinks and portion size in recent years affect obesity? 8.2.2 and 8.2.3

Answer 2

portion size has dramatically increased leading to increased intake of energy
also sugar sweetened beverages (sodas, fruit drinks, energy and vitamin drinks) have increased globally leading to and increase of energy intake with little or not nutritional value.

Question 3

How has eating out and fast food contributed to obesity? 8.2.4

Answer 3

frequency of eating outside the home has increased greatly in recent years…this shift has occurred in parallel with increasing obesity.
Food eaten outside the home of are prepared are higher in fat, salt, cholesterol and lower in fibre and calcium. also amount of trans fats in these foods has been shown to contribute to risk of weight gain and abdominal fat.

Question 4

Is there a link between snacking and obesity? 8.2.5

Answer 4

snacking has increased but there is little evidence that snacking itself has been linked directly to obesity…unless type of snacks consumed are poor.

Question 5

What is the 600 kcal deficit diet? 8.3.1.2

Answer 5

a systematic review reported that it produces and 11.7lb weight loss in 12 months
This diets reduces energy intake below expenditure and is acceptable and feasible for the patient.

Question 6

Discuss the usefulness of Low-Carb Diets and it’s adverse side effects. 8.3.2.2

Answer 6

often viewed as an alternative to a lowfat diet for weight loss
-weight loss, beneficial metabolic changes have been documented such as improvements in lipid profile and glycemic control even in absence of weight loss and with increase in saturated fat intake.

Adverse effects:fatigue, constipation, accumulation of ketone bodies, headache, impaired liver and kidney function and difficulties in maintaining weight loss after the diet.

need more studies to show whether or not longterm low carb diets are safe and effective or not.

Question 7

What is the usefulness of the moderate protein diet in weightloss? 8.3.2.3

Answer 7

suggested that increasing the intake of protein to about 30 to 35% of the diet may facilitate weightloss.
This is achieved through satiety and reduced energy consumption…greater thermogenesis, enhanced energy expenditure, protein balance, gat oxidation and greater maintenance of lean muscle mass
This type of diet looks promising however studies are very limited to date and further work needs to be done.