Metabolism and Energy Pathways

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In the context of weight loss, what physiological basis is mentioned in the reading material as a cause for weight regain?

Metabolic adaptations (correct)

Reduced appetite

Increased resting heart rate

Improved insulin sensitivity

During prolonged fasting, what is the primary source of energy for the brain?

Fatty acids

Gluconeogenesis from glycerol

Ketone bodies (correct)

Glucose from glycogen

In prolonged fasting, what is the primary origin of blood glucose?

Exogenous

Glycogen; Hepatic gluconeogenesis (correct)

Glucose, ketone bodies

Glucose

In the context of fuel utilization during early fasting, which statement is true?

Relies mainly on glucose from glycogen stores Signup and view all the answers

What physiological changes occur in severe weight loss with respect to cardiovascular and renal functions?

Development of tachycardia as a compensatory mechanism Signup and view all the answers

What is the primary goal of adapting to fasting?

Meet energy needs Signup and view all the answers

Why does the brain require a consistent supply of glucose?

To prevent coma and death Signup and view all the answers

What is the energy paradox in relation to the brain's energy needs?

The brain requires glucose but almost all energy is stored as fatty acids Signup and view all the answers

Which macronutrient is the most likely to favor energy storage and weight gain according to the carbohydrate-insulin model of obesity?

Carbohydrates Signup and view all the answers

Why does burning glycogen and protein result in a greater weight loss that is mostly due to water loss?

Glycogen binds more water during metabolism Signup and view all the answers

What is the primary purpose of liver glycogen?

Immediate release of glucose into the blood Signup and view all the answers

What is the main reason for sparing protein during fasting?

To maintain muscle mass Signup and view all the answers

How do high carbohydrate and high fat intake together cause fat storage?

By causing excess energy intake Signup and view all the answers

What is the role of insulin in response to a meal?

To promote glucose uptake by tissues Signup and view all the answers

What happens to blood glucose levels in early diabetes or insulin resistance?

Blood glucose levels increase significantly Signup and view all the answers

How does the body adapt to fasting in terms of protein usage?

The body spares protein to maintain lean tissue mass Signup and view all the answers

What is the consequence of decreased insulin sensitivity in the context of the carbohydrate-insulin model of obesity?

Increased fat storage and weight gain Signup and view all the answers

According to the meta-analysis, what is the main driver of weight gain?

Excess energy Signup and view all the answers

What is the impact of a higher protein diet during energy-reduced low-fat diets?

Offsets REE by about 150 kcal/d Signup and view all the answers

What is the body's main adaptation to fasting, according to the study?

Switching main fuels from glucose to fatty acids and keto acids Signup and view all the answers

In weight-reducing diets, what effect does macronutrient composition (fat to carbohydrate ratio) have on total weight loss?

Has no effect on total weight loss Signup and view all the answers

What signals does energy restriction and weight loss induce, according to the study?

Increase appetite and food intake, decrease metabolism Signup and view all the answers

What did the study find about the effect of high-protein diets on weight maintenance after weight loss?

Aids in weight maintenance after weight loss Signup and view all the answers

What is the body's main response to increase in appetite and food intake during energy restriction and weight loss?

Decrease in metabolism Signup and view all the answers

What are the metabolic complications associated with nutritional repletion, as discussed in the text?

Rapid shift of electrolytes and intracellular anions and cations to extracellular space Signup and view all the answers

During refeeding, what is a physiological change that may lead to edema?

Increased glycogen synthesis Signup and view all the answers

What is the aim of providing 100-150g of glucose during refeeding?

To avoid refeeding syndrome Signup and view all the answers

In response to diet-induced weight loss, what physiological change leads to a decrease in energy expenditure?

Reduction in physical activity Signup and view all the answers

What is the primary cause of decreased energy expenditure after weight loss, as mentioned in the text?

Reduced sympathetic drive Signup and view all the answers

What is the effect of increasing exercise on energy expenditure, according to the text?

Initial increments in energy expenditure can be greater than expected Signup and view all the answers

What may be the result of consuming a diet high in carbohydrates according to the carbohydrate-insulin model?

Increased insulin secretion and fat storage Signup and view all the answers

What is the basis for the 'metabolic advantage' associated with low-carb diets as mentioned in the text?

'Increased lipolysis and use of free fatty acids' Signup and view all the answers

What did the 6-year follow-up study reveal about the magnitude of metabolic adaptation and its relation to weight regain?

The magnitude of metabolic adaptation increased after 6 years but was not related to weight regain Signup and view all the answers

What is a likely consequence of consuming an isocaloric diet high in carbohydrates based on energy partitioning?

Preferential energy storage as body fat over body protein Signup and view all the answers