PEP/NEWS — Peptide intel. Daily.

Sebastian Mallaby is the Paul A. Volcker senior fellow for international economics at the Council on Foreign Relations, a two-time Pulitzer Prize finalist, and the author of six books, including More Money Than God, The Power Law, The Man W

Attia's AMA 86 digs into the freshest numbers on lean mass loss during GLP-1 receptor agonist therapy. His takeaway: patients who hit protein targets and do resistance training lose very little muscle — but most patients aren't being counseled to do either.

New findings show that senescent cells accumulate rapidly after a heart attack and amplify tissue damage rather than supporting repair. In younger, healthier tissue the immune system clears them quickly — in older tissue, they linger and make the injury worse.

Scientists linked disrupted calcium balance to accelerated aging in mice, then restored it using a well-known antidepressant. Both progeroid (rapid-aging) and normally aging mice showed lifespan gains — though the mechanism still needs work before it points toward a human application.

Researchers found that SIRT6 gene variants common in centenarians produce measurably fewer senescent cells throughout life. The data supports the view that controlling cellular senescence — not just any single pathway — is a key lever for exceptional longevity.

Part 3 of the Research Vials cancer series confronts the harder questions: where GH secretagogues sit on the risk continuum, what washout windows the literature suggests, and what the honest case against certain peptide stacks looks like. Required reading for any researcher thinking carefully about oncogenic risk.

Johnson lays out four cardiovascular protocols with cited evidence — not just biohacker lore. His blood pressure now tests lower than 90% of 18-year-olds, which makes the underlying stack worth examining even if you discount the personal branding.

Transcriptomic analysis of aging human brain tissue found that mitochondrial double-stranded RNA builds up with age — and builds up more in Alzheimer's disease. The finding adds a new thread to the mitochondrial dysfunction narrative that underpins much of current longevity research.

A review collects the current evidence for how gut microbial composition directly influences sarcopenia and neurodegeneration. In animal models, restoring a younger microbiome profile measurably slows both muscle and brain aging — though human translation remains in early stages.

Instead of a single whole-body age score, researchers tracked aging trajectories in individual cell types and found they predicted specific disease onset with meaningful lead time. The approach could eventually make biological age a clinically actionable — not just descriptive — number.

A new meta-analysis links short sleep to reduced lifespan, but Attia unpacks why the study design can't establish causation — and why the behavioral advice holds regardless of what the data ultimately proves.

A non-coding RNA strand found only in primates appears to worsen cellular senescence as tissues age. The discovery matters because it is human-relevant in a way many rodent findings are not.