The Science of Weight Loss

• A. Basal metabolic rate
• B. Total daily energy expenditure ✓
• C. Thermic effect of food
• D. Caloric threshold

Why: Total daily energy expenditure (TDEE) is the sum of all calories burned, including basal metabolism, physical activity, and the digestion of food. Basal metabolic rate is only one component of it.

• A. Physical exercise
• B. Digesting food
• C. Basal metabolic rate ✓
• D. Fidgeting and non-exercise movement

Why: For most sedentary adults, basal metabolic rate, the energy needed to keep the body functioning at rest, makes up roughly 60 to 70 percent of total daily energy expenditure.

• A. The heat produced when food is cooked
• B. The energy the body uses to digest, absorb, and process nutrients ✓
• C. The calories stored as body fat after eating
• D. The temperature change in the stomach after a meal

Why: The thermic effect of food is the energy expended to digest, absorb, and metabolize what you eat. It typically accounts for about 5 to 10 percent of total energy expenditure, and protein has the highest thermic effect.

• A. Increased muscle mass
• B. Loss of lean muscle tissue ✓
• C. Higher daily protein intake
• D. Greater physical activity

Why: Adults tend to lose lean muscle mass with age, and since muscle is metabolically more active than fat, this loss lowers basal metabolic rate.

• A. Muscle tissue burns more calories at rest than fat tissue ✓
• B. Muscle directly converts fat into energy during workouts
• C. Muscle prevents the thermic effect of food from occurring
• D. Muscle reduces the amount of food the body needs to digest

Why: Muscle is more metabolically active than fat, so each additional pound of muscle modestly increases the calories burned at rest, helping to support a higher basal metabolic rate.

• A. The ratio of protein to carbohydrates in a meal
• B. The relationship between calories consumed and calories expended by the body ✓
• C. The amount of water retained in body tissues
• D. The balance between good and bad cholesterol levels

Why: Energy balance refers to how calories taken in from food and drink compare to calories the body uses for metabolism, physical activity, and digestion. A surplus tends to lead to weight gain, while a deficit tends to lead to weight loss.

• A. Consuming 2,500 calories while burning 2,000 calories
• B. Consuming 1,800 calories while burning 2,200 calories ✓
• C. Consuming 2,000 calories while burning 2,000 calories
• D. Consuming 2,200 calories while burning 2,200 calories

Why: A calorie deficit occurs when energy intake is lower than energy expenditure. Consuming 1,800 calories while burning 2,200 calories creates a deficit of 400 calories, which promotes weight loss over time.

• A. Protein
• B. Carbohydrate
• C. Fat ✓
• D. Fiber

Why: Fat provides about 9 calories per gram, while protein and carbohydrates each provide about 4 calories per gram. This is why fat-rich foods are calorie-dense even in small portions.

• A. It contains no calories
• B. It helps preserve lean muscle mass and promotes feelings of fullness ✓
• C. It directly burns body fat
• D. It eliminates the need for exercise

Why: Adequate protein intake helps preserve muscle mass during a calorie deficit and is more satiating than carbohydrates or fats, which can help people feel full and reduce overall calorie intake. Protein does contain calories and does not directly burn fat.

• A. Intentional exercise
• B. Digestion of food
• C. Basal metabolic rate, the energy used at rest to maintain basic body functions ✓
• D. Fidgeting and small movements

Why: Basal metabolic rate accounts for roughly 60 to 70 percent of total daily energy expenditure for most sedentary and moderately active people. It covers essential processes like breathing, circulation, and cell repair, and it exceeds the energy used in exercise for most individuals.

• A. Gentle stretching
• B. Moderate to vigorous aerobic exercise such as running or cycling ✓
• C. Slow, controlled balance poses
• D. Standing still with light arm movements

Why: Aerobic exercise at moderate to vigorous intensity raises heart rate and energy expenditure substantially, burning more calories per minute than stretching, balance work, or standing still.

• A. It burns more fat than cardio during the workout
• B. It helps preserve and build lean muscle mass, which supports a higher resting metabolic rate ✓
• C. It directly converts muscle into fat-burning tissue
• D. It eliminates the need for a calorie deficit

Why: Muscle tissue is more metabolically active than fat tissue. Resistance training helps maintain or build lean mass during a calorie deficit, which supports a healthier metabolic rate and better body composition.

• A. Losing fat from a targeted body area through exercise; it is effective
• B. Losing fat from a targeted body area through exercise; it is not effective ✓
• C. Burning calories only during short bursts; it is effective
• D. Reducing muscle soreness in one area; it is effective

Why: Spot reduction is the idea that exercising a specific body part burns fat from that area. Research shows fat loss occurs across the body in a pattern largely determined by genetics, so targeted exercises like crunches do not selectively burn belly fat.

• A. Exercise alone is sufficient to produce significant weight loss without dietary changes
• B. Diet typically plays a larger role in creating a calorie deficit, while exercise supports the deficit and provides other health benefits ✓
• C. Diet and exercise contribute equally in all situations and for all people
• D. Exercise has no meaningful effect on weight loss

Why: Because it is generally easier to reduce calorie intake than to burn large amounts through exercise, diet tends to drive most weight loss. Exercise adds to the calorie deficit, preserves muscle, and improves cardiovascular and metabolic health.

• A. Excess Post-exercise Oxygen Consumption; the body uses more oxygen after intense exercise to recover, slightly raising calorie burn afterward ✓
• B. Estimated Physical Output Calculation; a formula for measuring workout intensity
• C. Enhanced Protein Oxidation Cycle; a process that only occurs during fasting
• D. Energy Pathway Override Chemical; a hormone that stops fat storage

Why: EPOC describes the elevated oxygen consumption that continues after intense exercise as the body restores its systems. It increases total calorie burn somewhat, though the effect is modest and should not be overstated.

• A. Restrained eating
• B. Emotional eating ✓
• C. Intuitive eating
• D. Cognitive dissonance

Why: Emotional eating refers to using food to cope with feelings rather than to satisfy physiological hunger. It is a common psychological pattern that can contribute to excess calorie intake and weight gain.

• A. To count the exact number of vitamins consumed each day
• B. To increase awareness of eating patterns, portion sizes, and triggers ✓
• C. To replace the need for physical activity
• D. To compare your body weight with others in your group

Why: Self-monitoring through a food diary increases awareness of what, when, and why a person eats. Research consistently links regular self-monitoring with greater weight loss success.

• A. Feeling well rested after sleep
• B. Seeing food advertisements or smelling appetizing food ✓
• C. Drinking a full glass of water before a meal
• D. Completing a 20-minute walk

Why: Environmental cues such as seeing or smelling food can trigger eating through learned associations, even without physiological need. Recognizing these external triggers is a key strategy in behavioral weight management.

• A. Eating as quickly as possible to save time
• B. Paying full attention to the experience of eating, including taste, texture, and hunger signals ✓
• C. Avoiding all foods that contain sugar or fat
• D. Eating only while standing at the kitchen counter

Why: Mindful eating involves focusing on the sensory experience of food and noticing physical hunger and fullness cues. This practice can reduce overeating by slowing down the meal and improving satisfaction.

• A. Their metabolism stops working entirely
• B. Old habits and eating triggers return when support and self-monitoring decline ✓
• C. Weight loss always causes permanent damage to the body
• D. Drinking water after meals causes fat storage

Why: Weight regain is often linked to the return of previous habits and environmental triggers once structured support and self-monitoring stop. Maintaining long-term behavior changes is a central focus of weight management psychology.

• A. Leptin
• B. Ghrelin ✓
• C. Insulin
• D. Cortisol

Why: Sleep deprivation raises ghrelin, the hormone that stimulates hunger, while leptin, which signals fullness, tends to decrease. This combination can increase appetite and food intake.

• A. 4 to 5 hours
• B. 7 to 9 hours ✓
• C. 10 to 12 hours
• D. 5 to 6 hours

Why: The American Academy of Sleep Medicine and other health organizations recommend 7 to 9 hours of sleep per night for most adults, a range linked to better metabolic health and weight regulation.

• A. It improves insulin sensitivity
• B. It has no effect on insulin
• C. It decreases insulin sensitivity, raising blood sugar ✓
• D. It eliminates the need for insulin

Why: Short sleep reduces insulin sensitivity, meaning cells respond less effectively to insulin. Blood sugar stays elevated for longer, which over time raises the risk of weight gain and type 2 diabetes.

• A. Greater preference for high-calorie, high-sugar foods ✓
• B. Greater preference for raw vegetables
• C. Reduced desire to eat any food
• D. Increased physical activity levels

Why: Studies show sleep-deprived people often crave calorie-dense, high-carbohydrate foods, and the brain's reward responses to food can be heightened when tired, which can lead to overeating.

• A. Using screens in bed until falling asleep
• B. Drinking caffeine late in the afternoon
• C. Keeping a consistent sleep and wake schedule ✓
• D. Napping for several hours in the evening

Why: A consistent sleep schedule helps regulate the body's circadian rhythm, supporting more restful sleep and healthier hormone patterns. Late caffeine, evening screen use, and long evening naps can all disrupt sleep.

• A. Following a very low-calorie diet for the shortest possible time
• B. Regular physical activity and consistent self-monitoring of eating habits ✓
• C. Eliminating an entire food group from the diet
• D. Relying primarily on appetite-suppressing supplements

Why: Research on successful weight loss maintainers, such as the National Weight Control Registry, shows that regular physical activity and ongoing self-monitoring (like tracking food intake or body weight) are among the most consistent behaviors linked to keeping weight off over time.

• A. About 0.5 to 1 kilogram (1 to 2 pounds) per week ✓
• B. About 3 to 4 kilograms (6 to 8 pounds) per week
• C. About 2 kilograms (4 pounds) per day
• D. There is no recommended rate; faster is always better

Why: Losing roughly 0.5 to 1 kg (1 to 2 lb) per week is generally considered safe and sustainable. Faster losses often include significant water and muscle loss and are harder to maintain, increasing the likelihood of regaining the weight.

• A. Metabolism permanently stops working after any diet
• B. The body adapts by increasing hunger hormones and reducing energy expenditure, making maintenance difficult ✓
• C. Fat cells multiply permanently once weight is lost
• D. Drinking water with meals causes weight to return

Why: After weight loss, the body often increases hunger-promoting hormones like ghrelin, decreases satiety hormones like leptin, and lowers energy expenditure. These adaptations make it harder to sustain the reduced intake, which contributes to weight regain.

• A. Strictly banning all favorite foods to stay disciplined
• B. Eating only at specific fixed times and skipping all snacks
• C. Building meals around whole foods, adequate protein, and vegetables while allowing occasional flexibility ✓
• D. Replacing all meals with liquid meal replacements indefinitely

Why: Sustainable approaches emphasize nutrient-dense whole foods, adequate protein and fiber for fullness, and flexibility. Rigid restriction often leads to cravings and rebound eating, while flexible patterns are easier to follow long term.

• A. Sleep has no measurable effect on appetite or body weight
• B. Short sleep is linked to increased hunger hormones and a higher risk of weight gain ✓
• C. Sleeping more than 10 hours per night is required for weight loss
• D. Sleep only affects weight in people who exercise

Why: Insufficient sleep disrupts hormones that regulate appetite, increasing ghrelin and decreasing leptin, and is associated with greater calorie intake and higher risk of weight gain. Adequate sleep supports both appetite regulation and recovery for physical activity.