An unprecedented window into how diseases take hold years before symptoms appear

Study and “functional reserve”

• Commenters link the Biobank results to long-known ideas of “functional” or “cognitive” reserve: organs and cognition can compensate for damage for years before symptoms appear.
• Examples given: kidneys losing nephrons until reserve is exhausted; Alzheimer’s starting with mild forgetfulness decades before disability; HIV and SARS‑CoV‑2 effects being buffered by higher cognitive reserve.

Kidney function and eGFR anecdotes

• A healthy, fit person failed kidney-donor screening due to chronically low-but-stable eGFR, which later improved slightly; others note eGFR is an estimate that fluctuates and declines roughly 1 point/year after 30.
• Creatine supplementation and contrast dye from imaging are mentioned as possible confounders or harms.
• Cystatin C and direct GFR tests are cited as more accurate when donation risk is evaluated.

What “functional reserve” actually is

• Some argue it’s not a single thing: redundancy at many levels (two kidneys, many nephrons, vascular elasticity, etc.) add up to reserve.
• One explanation: only a subset of glomeruli filter at any given time; reserve units activate when others fail.
• Analogies are made to redundant cloud infrastructure; gradual failure only shows when enough components are lost.

Preventive care, incentives, and inequality

• Strong support for prevention as vastly cheaper than late treatment; used to argue for centralized systems like the NHS.
• Others note perverse US incentives: prevention often out-of-pocket, treatment often insured.
• Debate over whether “anyone can afford” prevention; critics highlight food deserts, unsafe neighborhoods, difficulty taking time off work.

Screening, diagnostics, and overtesting

• Several warn that “more data” is not always better: many screenings (blood panels, imaging) produce false positives and harmful interventions.
• PSA testing and widespread prostate cancer illustrate overdiagnosis vs meaningful disease.
• Popular longevity frameworks and tests (e.g., coronary calcium scans, VO2 max, DEXA) are seen by some as mainly for “worried well” enthusiasts; often they don’t change recommended lifestyle actions.
• CT scan radiation risk (one commenter cites “~5% of cancers”) is raised as a reason to avoid unnecessary imaging.

Self-healing, early detection, and Covid

• Commenters stress that the body often clears early cancers and infections unnoticed; “too-early” detection can mislead statistics and trigger unhelpful care.
• Some argue SARS‑CoV‑2’s long-term effects resemble known post-infection phenomena; others challenge blanket claims without specific evidence, noting huge publication volume alone proves little.