Ch 10- Energy balance

What is energy?

The ability to do work.

Define energy intake.

Total energy consumed from food.

What does energy expenditure refer to?

Energy used to fuel basal metabolism, physical activity, and processing food.

What is energy balance?

When energy intake is equal to energy expenditure.

What are the three energy-yielding nutrients?

Carbohydrates, lipids, and proteins.

How much energy does alcohol provide?

7 kcal/g, but it is not a nutrient.

What percentage of energy expenditure is attributed to basal metabolic rate (BMR)?

Approximately 60-75%.

What are the 3 main purposes for burning energy?

Basal metabolic rate

Diet induced thermogenesis

Physical activity

What is basal metabolic rate (BMR)?

The amount of energy the body needs to perform its most basic, life-sustaining functions. Dictated by genetic

What is diet-induced thermogenesis (DIT)?

The energy used and dissipated as heat following food intake.

Which nutrient requires more energy to process in DIT?

Protein.

What is the main controllable factor that determines BMR?

Lean body mass.

What is physical activity in terms of energy expenditure?

Voluntary movements of the body that burn energy.

What happens when energy intake exceeds energy expenditure?

Excess energy is stored as lipid within adipocytes.

What leads to weight gain?

An increase in fat mass, lean mass, water mass, or glycogen storage due to consistent energy surplus.

What occurs during an energy deficit?

Lipids are removed from adipocytes, decreasing fat mass and weight.

What causes weight loss?

A decrease in fat mass, lean mass, water mass, or glycogen storage due to consistent energy deficit.

What is obesity?

A condition characterized by excessive body fat, often measured using BMI.

What are some complications of having too much stored energy?

Increased risk of obesity-related health issues.

What are the strengths of assessing body size?

Provides insight into health risks associated with weight.

What are the limitations of assessing body size?

May not accurately reflect body composition or health status.

What strategies can help maintain a healthy energy balance?

Balanced diet, regular physical activity, and monitoring energy intake.

What are common characteristics of eating disorders?

Distorted body image, unhealthy eating patterns, and potential health risks.

What are risk factors for developing eating disorders?

Genetic, psychological, and environmental influences.

What are adipokines?

Messengers secreted by adipocytes that communicate with other body tissues.

What effect do adipokines have below a certain level of fat mass?

They have a health-promoting maintaining effect.

What happens to adipokine secretion above a certain level of fat mass?

They are more likely to promote low-grade inflammation and disease.

What is leptin?

An adipokine (released by adiposites) that acts on the brain's hypothalamus to promote satiety.

How does leptin affect appetite when fat cells increase?

More leptin is released, which decreases appetite and promotes an energy deficit.

What is leptin resistance?

A condition where individuals with obesity do not respond effectively to leptin.

When did the Canadian Medical Association declare obesity a disease?

In 2015.

What are some factors contributing to obesity?

Genetic and lifestyle factors, with physical, mental, and social effects.

What evidence supports the link between genetics and obesity?

Identical twins have a stronger correlation in BMI than fraternal twins.

What are genome-wide association studies finding in relation to obesity?

They have found ~100 mutations more common in individuals with obesity, mainly associated with appetite.

Is obesity caused by a single gene mutation?

No, it is polygenetic in nature.

What is the difference between appetite and hunger?

Appetite is the drive to consume food, while hunger is the physiological need to eat.

What is satiation?

The feeling of fullness during eating that eliminates the desire to continue eating.

What is satiety?

The feeling of fullness after a meal that determines the time before the desire to eat returns.

How does the environment affect food consumption?

An abundance of food cues promotes high energy consumption, creating an obesogenic environment.

What psychological factors can affect eating and exercise?

Stress, mental health status, and self-perception can influence both eating and exercise habits.

What role does social psychology play in obesity?

It affects food preferences, body size acceptance, and physical activity.

What is the main controllable factor affecting energy expenditure?

Physical activity (PA).

What percentage of Canadians meet the recommended physical activity guidelines?

Only 15% meet the recommendation of 150 minutes of moderate to vigorous physical activity per week.

What is the relationship between energy imbalance and obesity?

It is easy to out-eat exercise, making it difficult to lose weight through exercise alone.

How do different individuals handle energy differently?

Differences in BMR, hormonal activity, genetics, and microbiome can affect energy balance.

What is the role of Firmicutes in individuals with obesity?

They are better at harvesting energy from food, increasing energy intake.

What are key appetite hormones involved in energy balance?

Neuropeptide Y promotes feeding; Ghrelin promotes appetite; Peptide YY reduces appetite after meals.

What is lipoprotein lipase (LPL)?

An enzyme on adipocytes that captures triglycerides and promotes fat storage.

What happens to LPL levels following weight loss?

LPL levels increase following weight loss.

What is the primary effect of leptin on the body?

Leptin inhibits appetite and promotes energy expenditure.

What condition may obese individuals develop regarding leptin?

Leptin resistance.

What does body composition refer to?

The proportion of fat mass versus lean mass in the body.

What is a healthier body composition associated with?

More lean mass and less fat mass.

Why is Body Mass Index (BMI) limited in assessing body composition?

BMI does not fully capture body composition as it only considers height and weight.

What is the better measure for determining body composition than weight?

Percent body fat, which expresses fat mass as a percentage of total mass.

Where is visceral fat located, and why is it significant?

Visceral fat is found around organs and is associated with higher disease risk.

What is subcutaneous fat?

Fat found under the skin.

What is DEXA used for?

To measure body composition using low dose X-ray scans.

What is the significance of waist circumference in assessing obesity?

Waist circumference helps assess body composition and health risk when combined with BMI.

What is the male threshold for waist circumference indicating obesity?

102 cm.

What is the female threshold for waist circumference indicating obesity?

88 cm.

What is the recommended weight loss rate to avoid negative physiological changes?

0.5 to 2 lbs per week.

What is the energy deficit needed to lose one pound of fat?

A deficit of approximately 3500 kcal.

What percentage of body weight loss is associated with reduced disease risk?

A 5-15% reduction in body weight.

What is the National Weight Control Registry?

A database of individuals who have lost 30+ lbs and maintained the loss for at least one year.

What are some strategies for decreasing food intake?

Tracking food intake, portion control, and consuming whole foods.

What is willpower in the context of weight management?

The ability of the thinking brain to override other signals related to eating.

What psychological aspect impacts appetite and desire to be active?

Psychological health.

What is self-efficacy?

The belief in one's ability to achieve a certain task.

What is emotional eating?

Eating used to cope with negative emotions or feelings.

What is mindfulness in the context of eating?

The practice of being aware of and experiencing the present moment without judgment.

Why do many people regain weight after losing it?

Due to decreased energy expenditure and changes in appetite regulation.

What happens to fat cells when weight is lost?

Fat cells shrink but do not go away.

How many fewer calories does a formerly obese individual require to maintain their weight?

Approximately 300-400 kcal less per day compared to someone who never gained weight.

What are fad diets?

Diets that are popular for a period and often promise quick results that are not sustainable.

What is a red flag of fad diets regarding exercise?

They do not recommend exercising.

How do fad diets typically restrict food intake?

They are overly restrictive and significantly limit what foods can be consumed.

What financial aspect is a common red flag for fad diets?

They are often expensive and require the purchase of supplements or pre-packaged foods.

What type of endorsements are often associated with fad diets?

They are endorsed by celebrities and influencers who are paid to promote the product.

What phrase commonly appears in promotional materials for fad diets?

The words 'lose weight fast'.

What is a healthy diet characterized by?

It promotes a healthy dietary pattern that meets nutrient needs and can be maintained throughout life.

What is the recommended weight loss rate for a healthy diet?

Promotes reasonable weight loss of 250 g to 1 kg per week.

What is a key difference between healthy diets and fad diets regarding physical activity?

Healthy diets promote physical activity, while fad diets advertise weight loss without the need to exercise.

What is the best way to increase lean body mass?

Through muscle-building exercises.

What is Orlistat used for?

It blocks the activity of lipase in the small intestine, decreasing fat absorption.

What does Liraglutide do?

It increases the activity of GLP-1 and promotes satiety.

What is a common risk factor for eating disorders?

Genetics, female gender, socio-cultural factors, and personality traits such as perfectionism.

What characterizes binge eating episodes?

They occur in a specific amount of time, typically in the absence of hunger, and are associated with feelings of guilt and shame.

What is Bulimia Nervosa?

It involves binge eating followed by compensation behaviors such as vomiting or excessive exercise.

What distinguishes Binge Eating Disorder from Bulimia Nervosa?

Binge Eating Disorder involves binge eating without compensation.

What is Anorexia Nervosa characterized by?

A significant restriction in energy intake leading to an unhealthfully low body weight.

What is Night Eating Syndrome?

An increase in food intake at night, with abnormal eating patterns and lack of morning hunger.

What is Orthorexia Nervosa?

An obsession with eating healthy that has negative psychological implications.

What is the main treatment strategy for eating disorders?

Psychological treatments, such as cognitive behavioral therapy (CBT).

What is a recommendation for achieving a healthy energy balance?

Moderate caloric intake and regularly participate in physical activity.

What should individuals do if obesity significantly impacts their health?

Consult a doctor for potential medical interventions.

What is a common symptom of binge eating disorder?

Loss of control during eating episodes.

What can excessive vomiting in Bulimia Nervosa lead to?

Damage to teeth and electrolyte imbalances.

What is a sign of Anorexia Nervosa?

An intense fear of weight gain and a distorted perception of body weight.

What does the treatment for eating disorders often begin with?

Diagnosis by a healthcare professional.