Journal & science

The science of longevity,
made readable.

Long-form, physician-authored writing on hormones, skin, peptides, lasers and the evidence behind whole-body longevity medicine. Including the negative findings most clinics won't publish.

Written by Dr. Dusan Sajic, MD PhD Evidence cited, limits stated
Trend Radar

The September Longevity Medicine Trend Radar: 10 Signals That Change What We Measure

September 2026: semaglutide and lifespan in mice, four FDA approvals, a voice-based aging clock and an AI aging benchmark, each graded by evidence.

Longevity Protocol

Most Supplements Are Wasted on Most People. Test First.

The bloodwork that changes a supplement decision, the habits no capsule outruns, a 1.2 g/kg protein estimate and the short list of supplements that earn a place.

Measuring What Matters

Look Good. Feel Strong. Know What Changed.

Waist tape, DEXA or MRI: how visceral fat is really measured, why removing fat is not the same as better health, and what the CBL-514 headline does not prove.

Longevity Testing

Your Labs Are Normal. That Was Never the Question.

The 13 blood tests behind a longevity panel, grouped under three questions: how fast you are aging, what is quietly straining the system, and which “normal” results deserve a second look.

Protein & GLP-1 Care

The Scale Is Moving. What Are You Protecting?

The four-part plan that protects lean mass on a GLP-1 medicine, and what the 14-person ProGo salmon-peptide study did and did not test.

Molecular Aging

An Enzyme Removed a Mark We Thought Was Permanent.

CMLase stripped one glycation mark from lab-treated human tissue, not living skin: what it proved, what glycation tests can tell you, and the plan that works today.

Treatment Decoder

Chemical Peels vs. Lasers: The Percentage Is Only One Variable.

Jessner, TCA, CO2, Er:YAG, Fraxel, MOXI: how peel depth really works, a full peel and laser comparison, and the questions that expose a vague plan.

Iron & Recovery

Your Lab Says Normal. Your Hair May Disagree.

ASH now diagnoses iron deficiency at ferritin 30 or below: why a “normal” result can still be low, what it means for hair shedding and CO2 recovery, and what to do when ferritin will not move.

AI Drug Discovery

AI Moved Six Aging Clocks. Did It Reverse Aging?

An AI-discovered fibrosis drug shifted proteomic aging clocks in a small trial, but not the mortality clocks: what moved, what didn't, and which tests matter now.

Skin Recovery

“I’m Doing Everything Right. Why Is My Skin Getting Worse?”

Stacked actives, procedures, sun and stress can outpace your skin’s ability to repair: the Recovery Gap, what aggressive CO2 taught us, and how to measure real recovery.

Skin Quality

Stop Guessing. See What Your Skin Actually Needs.

Firmness, surface, tone and glow: the four skin quality parameters from a 2025 consensus Dr. Sajic co-authored, with a self-assessment and treatment sequence.

Trend Radar

The August Longevity Medicine Trend Radar: 10 Signals Reshaping Prevention, Muscle, and Aesthetics

August 2026: the UK’s oral GLP-1, a heart-outcomes label for tirzepatide, new under-eye, chin and knee options, and three studies that sharpen how we measure aging.

Microbiome

The Face Mite Isn't What's Aging You. The Bacteria You Can't See Are.

Demodex is gross and mostly harmless. The bacteria on your face shift with age, track wrinkles and elasticity, and decide how you heal after CO2 laser. The 60-second swab that maps them.

Treatment Planning

How Often Should You Actually Get Treatments?

Typical intervals for lasers, collagen treatments, internal protocols and diagnostics, plus a sample 12-month calendar.

Philosophy & Longevity

Aging Isn't Skin Deep: Why I Treat It From the Inside and Out

How longevity medicine, CO2 lasers and dermatology fit together in one practice: one disease process, treated from two directions.

Laser & Recovery

The Complete CO2 Recovery Guide

Pre-care, internal optimization, and validated recovery products: the protocol that separates exceptional CO2 laser outcomes from avoidable complications.

Cancer Prevention

What If We Could See Cancer Coming 5 Years Early?

A landmark Cell study identified a 14-protein blood signature that predicts lung cancer 5+ years before diagnosis. What it means, what you can do now, and how we apply it to skin.

Metabolic Fitness

The Metabolic Fitness Gene That Cuts Disease Risk by 60%

A million-person Nature study identified FNIP1, a metabolic brake gene. People without it get 60% fewer metabolic diseases. Here is how we measure and mimic it.

Zombie Cells

A Sunburn on Your Back Could Be Fueling Cancer on Your Toe

Senescent zombie cells broadcast inflammatory SASP signals through your blood. The systemic SASP hypothesis, the transplant-patient proof, and how CO2 laser and DNA repair fit in.

Combination Treatments

One Treatment Won't Save You. The Combination Will.

Aging is five mechanisms at once. Why the best results come from a coordinated, measured protocol of CO2, ultrasound, RF, biostimulators and strategic filler.

Microbiome

The Invisible Army on Your Skin That Decides How You Age

Your skin microbiome shapes UV response, inflammation and aging. What the research shows, how we test it, and how to support it.

Field Damage

How Did I Get Cancer Somewhere the Sun Never Burned?

Past sun exposure, distant-site cancer and one connected system: what research shows about systemic inflammation, the tests worth ordering, and the lasers and skincare that move the biology.

Longevity Science · Part 1 of 4

Hormonal Longevity & Skin Health: The Complete Guide

How estrogen, testosterone, thyroid, cortisol and insulin decide how skin ages, plus the full longevity bloodwork panel.

Peptide Research

Validating the Crowd: The Truth About BPC-157

66% miracle, 20% nothing, 19.6% neurological risk: our systematic analysis benchmarked against clinical controls.

Senescence & Longevity

Zombie Cells: What They Are, Why They Matter, and How to Clear Them

Cellular senescence, the SASP, and what the 2026 senolytic evidence really shows.

Laser & Longevity

Skin Cancer & Aging: The Same Disease

Shared biology, and the landmark studies showing laser can measurably reset both.

Laser & Longevity

The Skin Health Reset: Seeing the Invisible

See the hidden photodamaged field, treat it with high-density CO2, protect it afterward.

Laser & Longevity

The Wavelength That Rewrites Your Skin's Story

Nordlys 1940nm: 83% epigenetic reversal in a first-in-human pilot, with a fraction of CO2's downtime.

Philosophy & Longevity

From Vanity to Longevity

The shift from treating how skin looks to protecting how skin lives.

Skincare Science

How to Pick the Right Vitamin C

Why most serums fail: pH, stability, formulation, and how to know yours is actually working.

Injector's Deep Dive

Under-Eye & Tear Trough Filler

Anatomy, honest candidate selection, and the complications nobody warns you about.

Fellowship-Level Insight

The Delicate Art of Treating Festoons

Why the wrong treatment makes them worse, and the sequential approach that helps.

Longevity Science

Your Skin Is Aging You From the Inside Out

The inflammaging axis, and the tests that replace guessing with knowing.

EMF & Longevity

The $5 Panic: Why Your Watch Isn't Killing You

SAR physics vs. viral fear, and why a wearable is one of your best longevity investments.

Monthly Digest · Trend Radar

10 Breakthroughs That Changed Longevity Medicine This Month

July 2026: the FDA peptide vote, GLP-1s beyond weight loss, a 92% skin-cancer reduction, and more.

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