What actually moves the needle on health — and how sure we are
This is a source-grounded appraisal of the nutrition, exercise, and lifestyle evidence: what an exposure does, for whom, how much, and how confident we should be — with every claim traced back to the study or guideline it came from.
It is built to answer one question: would this change what someone should do, on an outcome they care about, in a way they couldn’t already have reached? If not, it isn’t here.
The guides
Start here — each is a short, ranked, honestly-caveated guide for a particular situation:
- The Biggest Health Levers for a Typical Adult — the largest levers for a typical drifting-into-middle-age Western adult, sorted so the guidance helps the majority without harming the leaner minority.
- The Biggest Health Levers After 70 — how those priorities invert with age: function, muscle, bone and falls move to the front, and aggressive weight loss flips from a lever into a hazard.
- Carnivore vs Animal-Based: A Head-to-Head — a strict-carnivore vs a medium-fat animal-based pattern, for someone with elevated cardiometabolic risk.
- What to Measure: A Minimal Health Checklist — the small set of readily-capturable health metrics that do most of the work of placing you in the right group.
Common questions, answered honestly
Appraisals of the questions people actually ask — with the effect sizes where they exist, and a plain statement of what the evidence can’t yet settle:
- Are artificial sweeteners bad for us? — cancer, appetite, insulin, weight, cravings — and why the answer depends entirely on what the sweetener replaces.
- Is organic food better for us? — pesticides, nutrients, and outcomes, and why “pasture vs grain” often matters more than the organic label itself.
- Do we need fibre in our diet? — cholesterol, gut transit, blood sugar and satiety, soluble vs insoluble — and why “essential” oversells a modest, supporting lever.
Beyond the guides, you can follow the links into the underlying claim pages — the frameworks, concepts, tensions and diagnostics they are built from.
What makes it different
- Ranked by effect size × certainty — big rocks first. Most of the achievable benefit sits in a handful of large exposures (not smoking, staying active, avoiding excess visceral fat, sleeping enough). The endless refinements share what’s left. We say so plainly instead of burying the large levers among small ones.
- Honest about uncertainty. We keep four states apart — benefit, harm, no meaningful effect, and not enough evidence to say — and we never let the last two blur together. Where the evidence is thin, we say the evidence is thin.
- Surrogates are not outcomes. A number that moves (cholesterol, blood sugar) is not the same as a life lived longer or better. We flag when a result rests on a marker rather than on what you actually care about.
- Symmetric standards. A long-standing recommendation earns no free pass from age or authority; a contrarian claim earns none from novelty. The same scrutiny applies to both.
- Gaps are findings. When the levers left for you are small and uncertain, that is the answer — it tells you it’s okay to stop optimizing.
Read this first — the honest limits
- This appraises evidence; it does not prescribe. It says what the evidence shows for a group of people. Selecting, dosing, screening for contraindications, and managing your medications are things only a clinician who knows you can do. This is not medical advice.
- A group is not a person. Every finding is about a reference class. You may differ from it in ways that matter — which is exactly the judgment that belongs to you and your clinician, not to a page.
- The loop is open. This grades whether the reasoning is internally sound and faithful to its sources — not whether following it made anyone better off. A clean, well-sourced page can still be wrong about the world. Nothing here has been tested against real outcomes, and we don’t pretend otherwise.