Chapter 24 — Exercises

Three tiers. 🔄 retrieval; 🪞 reflection.

⚠️ A note before starting. Several exercises here involve reflecting on your own weight history. If that is distressing, or if you have an eating disorder history, do the Tier 1 and Tier 3 items and skip the 🪞 section. That is a legitimate answer and this book means it.

Tier 1 — Recall and Comprehension

R1. State the four numbered claims with their verdicts. ⚠️ Which one does the chapter say was defensible in 2015 and isn't now?

R2. ⚠️ Give §24.1b's determinants of body weight. Which is described as the most actionable and least discussed?

R3. What is the heritability range for BMI, and what is it comparable to? ⚠️ Why doesn't that contradict the environmental explanation for population-level change?

R4. Give §24.2's asymmetry table. ⚠️ Which row does the chapter say people most underestimate, and why?

R5. What is adaptive thermogenesis? ⚠️ What is established about it, and what is disputed?

R6. Describe the Biggest Loser follow-up: what it found, and four reasons not to generalize it.

R7. ⚠️ What did Sumithran et al. (2011) measure, what did they find, and what was the crucial finding about duration?

R8. Explain why §24.5 is described as "the bigger half."

R9. State the three models of weight regulation and one strength and one weakness of each. ⚠️ What asymmetry must any model explain?

R10. Give the National Weight Control Registry's common features. ⚠️ State the survivorship problem in your own words.

R11. ⚠️ What did the DPP achieve, at what weight loss? What did Look AHEAD find, and what did it not find?

R12. Give §24.8b's rate of loss, deficit size and protein target for a deficit. ⚠️ What are the three explanations for a plateau, in order of likelihood?

R13. ⚠️ Name four documented consequences of weight stigma. Which is described as the operative one for clinicians?

R14. ⚠️ Give the trial results for semaglutide and tirzepatide, and say what SELECT added.

R15. ⚠️ Give five caveats to the GLP-1 medications. Which does the chapter say is not optional?

R16. What are bariatric surgery's outcomes, and its costs? ⚠️ Why does diabetes remission often occur before much weight is lost?

Tier 2 — Application

A1. 🔄 The eight situations. Using §24.14b, give the appropriate approach for each:

a) A 52-year-old with prediabetes and a BMI of 33 b) A 29-year-old with a BMI of 27, normal markers, who "wants to be healthier" c) A 44-year-old who has lost and regained 15 kg five times and is distressed about it d) A 71-year-old who has unintentionally lost 6 kg in a year e) A 34-year-old who gained 14 kg in the eight months after starting a new medication f) A 16-year-old whose parent is worried about their weight g) A 38-year-old with obstructive sleep apnoea h) Someone who restricted severely in their twenties and now avoids the scale

A2. The plateau. Someone has lost 9 kg over five months and hasn't moved in three weeks.

a) ⚠️ List §24.8b's three explanations in order of likelihood. b) What should they do first? Be specific. c) ⚠️ Under what circumstances is the correct answer "nothing — stop here"?

A3. The energy gap, both ways. Population weight gain corresponds to a small daily surplus.

a) State the encouraging reading. b) ⚠️ State the misleading reading and give the two reasons it fails. c) Someone says: "so obesity is just fifty calories a day of laziness." ⚠️ Write the reply.

A4. Set the expectation. Write, in under 80 words, what you would tell someone starting a behavioural weight-loss programme, covering:

• ⚠️ Expected magnitude · expected trajectory · what will happen to appetite · what the maintenance plan needs to be

A5. Read the trial. Look AHEAD achieved sustained modest weight loss and did not reduce cardiovascular events.

a) ⚠️ Does this show lifestyle intervention doesn't work? Justify carefully. b) What DID it improve? c) ⚠️ How should this be presented to a patient with type 2 diabetes considering the programme?

A6. The medication conversation. Someone asks whether they should take a GLP-1 agonist.

a) ⚠️ What four things do you need to know first? b) What must accompany the medication? (§24.11) c) ⚠️ What happens if they stop, and how should that shape the decision?

Tier 3 — Analysis and Synthesis

S1. Mechanism before treatment. §24.11 notes the drugs work because §24.5 identified the mechanism.

a) ⚠️ How often does this sequence occur in this book? Name every case you can find. b) Name two cases where a clean mechanism did NOT produce a working intervention. (Chapters 13 and 19 both have one.) c) ⚠️ What distinguishes the successes from the failures? Is it predictable in advance?

S2. The survivorship problem, generalized. §24.7 argues the NWCR can't establish a route.

a) ⚠️ Construct the study that would. What's the design, and why hasn't it been done? b) Find two other places in this book where the same survivorship structure appears. c) ⚠️ The chapter still highlights two registry findings as worth taking seriously. Was that justified, or special pleading?

S3. ⚠️ Stigma and candour. §24.9 finds weight stigma associated with healthcare avoidance and subsequent weight gain.

a) Write the clinical guidance you'd give a GP for raising weight with a patient. b) ⚠️ Is there ANY circumstance where blunt weight-focused language is justified? Defend your answer. c) A clinician says: "if I don't mention it, I'm failing them." ⚠️ Reply.

S4. The equity break. §24's economics block notes this is the first chapter where the best-evidenced options are not the cheapest.

a) ⚠️ What does that do to the argument this book has been making for twelve chapters? b) Design the policy response. What does it cost, and who opposes it? c) ⚠️ Is it defensible for a health system to fund bariatric surgery and not GLP-1 agonists, or vice versa? Argue both.

S5. Steelman the other side. §24.13 gives the weight-neutral case.

a) ⚠️ Write the strongest version of the argument that this chapter is still too weight-focused. b) Write the strongest version of the argument that it is not weight-focused enough. c) ⚠️ The chapter says the two sides are often arguing about different patients. Test that claim — find a case where they genuinely disagree about the same patient.

S6. 🔄 ⚠️ Theo's four attempts. Every one produced weight loss. Every one was regained.

a) For each, name the most likely mechanism of regain using §24.5 and §24.8b. b) ⚠️ What single change to attempt #1 would have most changed the twenty-year trajectory? c) He concluded he was the problem. ⚠️ Trace exactly how the evidence and the culture combined to produce that conclusion. Whose failure is it?

🪞 Reflection

⚠️ Skip this section if it isn't useful to you.

M1. ⚠️ Draw your own version of Theo's graph. How many attempts, how many worked, how many were maintained past two years?

M2. For your attempts, ⚠️ what was the maintenance plan? If the honest answer is "there wasn't one" — was that ever pointed out to you?

M3. ⚠️ Theo said "I just can't be the person who lost it." Have you ever attributed a physiological pattern to a personal failing? What would it change to stop?

M4. §24.9 says shame is not an intervention. ⚠️ Have you used it on yourself? Did it work?

M5. ⚠️ §24.11 notes some objection to the medications is about virtue rather than health — "it's cheating." Do you feel any of that? Would you feel it about a statin? Sit with the difference.