Why our waistlines expand in middle age: aging stem cells shift into overdrive

Original Article ↗ Hacker News Discussion ↗

CICO: True but Often Unhelpful as Guidance

  • Broad agreement that Calories In, Calories Out (CICO) is a thermodynamic identity; no one “beats” it.
  • Major disagreement over usefulness:
    • Critics say it’s like “earn more than you spend” in finance—definitionally true but poor practical advice, especially given hard-to-measure CI/CO and body adaptation.
    • Defenders argue people mostly miscount intake, underestimate portion sizes, and use complexity as an excuse.

Measurement, Biology, and Individual Variation

  • Several comments highlight: digestion differences, thermic effect of food, microbiome, hormones, meal timing, and satiety as reasons why “a calorie is a calorie” is an oversimplification in practice.
  • Others counter that these all still resolve to CICO; they just change the numbers. For actual dieting, tracking intake and weight trends is seen as most actionable.
  • Debate over whether one should assume 100% absorption; some say it’s a good working approximation, others point to labeling inaccuracies and visible undigested food as objections.

Adherence, Willpower, and Choice

  • One camp insists weight is “100% within your control”; another stresses non-binary “choice” shaped by genetics, medications, mental health, time, money, and hunger drive.
  • Strong emphasis from multiple sides that adherence and satiety matter more than abstract thermodynamics: whole foods, higher-satiety diets, or intermittent fasting often work better than pure macro-counting for many.
  • GLP‑1 drugs and TRT are presented as powerful new tools, but some question cost, access, and the implication that pharmacological help is now part of the “choice.”

Health vs. Beauty and Cultural Norms

  • Tension between “accept bodies as they are” and claims that obesity is a major, objective health burden comparable to smoking.
  • Side thread on whether attractiveness standards are biologically fixed or heavily culturally shaped.

Biological Mechanism and Interventions

  • Clarification that the article really describes an age-enriched preadipocyte population driving visceral fat expansion, not just generic “stem cells in overdrive.”
  • Speculation about viral therapies for adipocytes meets concern about metabolic side effects and off-target impacts, especially given adipocytes in organs like the brain.