Topic

Interventions

Sauna, Zone 2, HIIT, sleep optimization, sunlight, fasting, and the specific named compounds and protocols. The Act 4 territory — calibrated reads on what's worth doing.

2 articles

Calibrated Signal hero card reading 'Real Mechanism. Wrong Certainty.' over a stylized coronary artery, with the line: 5-Amino-1MQ, injected mice, and the heart arrow nobody measured.

InterventionsEvidence Critique

The Longevity Compound Promoted on Half a Mechanism

Its entire case for your heart is one biochemical arrow. I followed the other one, the one that runs the wrong way, and as a guy with a stent I walked away.

Jul 2, 2026 · 18 min read

A left-to-right flow diagram on a dark background reading: Metformin, acts in the gut, less citrulline, less nitric oxide, less blood flow to muscle. The heading reads, the concern did not disappear, it moved upstream.

Aging BiologyInterventions

The Gut May Be the Point: Metformin, Citrulline, and the Exercise Question

A new Nature Metabolism paper places metformin's main effect in the gut, not muscle. That eases one exercise-blunting fear and raises a sharper one: citrulline and nitric oxide.

Jun 3, 2026 · 16 min read