Definitions
Say what you mean by it.
Most disagreement in this field is vocabulary rather than evidence. Two groups use the same word for different things, and the argument that follows is unresolvable because it was never about the science.
These are the terms we use and what we mean by each. Where a term is contested or a measure is not yet validated, we say so rather than smoothing it over.
The biology of aging
What the science is actually measuring.
- Healthspan
- The period of life spent free of significant chronic disease and functional limitation. Distinct from lifespan, which counts years without regard to their quality.
- Lifespan
- Total years lived. A population's lifespan can rise while its healthspan does not, which produces a longer period of illness at the end of life rather than a longer period of health. That gap is the problem this field exists to close.
- Geroscience
- The study of the relationship between the biology of aging and the diseases of aging, on the premise that intervening in aging itself may delay several diseases at once rather than one at a time.
- Cellular senescence
- A state in which a cell stops dividing but does not die, remaining metabolically active and secreting inflammatory signals. Senescent cells accumulate with age and are implicated in tissue dysfunction.
- Inflammaging
- The chronic, low-grade inflammation that rises with age in the absence of infection, associated with frailty, cardiovascular disease and neurodegeneration.
- Proteostasis
- The cell's system for keeping proteins correctly folded, trafficked and degraded. Its decline is a shared feature of several neurodegenerative diseases.
- Biological age
- An estimate of physiological condition relative to chronological age, derived from biomarkers. Several methods exist and they do not always agree with one another, which is why we treat any single measure as provisional.
- Epigenetic clock
- A model that estimates biological age from DNA methylation patterns at selected sites. Widely used in research. Not validated as a clinical endpoint, and we do not present it as one.
- Biomarker of aging
- A measurable indicator that tracks the aging process and predicts outcomes better than chronological age alone. Few have been prospectively validated in humans.
How evidence is made
The vocabulary of a credible study.
- ICH-GCP
- International Council for Harmonisation Good Clinical Practice: the international ethical and scientific standard for designing, conducting and reporting studies involving human participants. Data generated to this standard is accepted across major regulators without rework.
- Pre-registration
- Publishing a study's hypothesis, endpoints and analysis plan before data collection begins, so that a result cannot be reframed after the fact. We treat it as a condition of support, not a courtesy.
- Multicentre study
- A study run at more than one site under a common protocol. Full site participation includes a role in design and in authorship, not only in enrolment.
- Investigator-initiated study
- A study designed and led by an academic investigator rather than by a commercial sponsor.
- Institutional review board
- An independent body that reviews research involving human participants for scientific merit and ethical acceptability before it may begin. Also called a research ethics committee.
- Independent replication
- Confirmation of a result by a laboratory with no stake in it. A finding that has not been replicated outside the originating group is a hypothesis, not a result.
- Real-world evidence
- Evidence about an intervention's effects drawn from routine care rather than a controlled trial. Strong for durability and generalisability, weaker for causal inference, and not a substitute for a trial.
- Endpoint
- The outcome a study is designed to move, specified in advance. A study that reports a different outcome than the one it registered has not demonstrated what it appears to demonstrate.
How work is funded
What the money actually is.
- Non-dilutive funding
- Capital provided without taking ownership. A grant is non-dilutive. An equity investment is not.
- Mission-aligned investment
- An investment made to advance a charitable mission rather than to maximise financial return. Any proceeds return to the Institute and are reinvested in the mission.
- Concentration limit
- A ceiling on how much may be committed to any single opportunity, set so that no one commitment can impair the Institute's other work.
- Conflict of interest
- A financial or personal connection that could reasonably be seen to influence a judgment. Our rule is disclose, recuse, abstain — not disclose and proceed.
- Implied endorsement
- The impression that support from an institution constitutes approval or validation of a product. Organizations we support may not describe themselves as approved, validated or endorsed by NGB.
Why this page exists
A definition is a commitment.
Every term above constrains something we can say. If we cannot state which outcome a program moves, we do not call it healthspan. If a measure is not validated, we do not present it as a clinical endpoint. Publishing the vocabulary is how those constraints become checkable rather than rhetorical.