Hi {{first name | there}},
I spent part of this month swimming in the Mediterranean, climbing Italian stairs, and eating almond granita in Sicily. I loved it.
Then came three conferences in Austin, Coronado, and New York, all in a week.
By the end, I felt spiritually amazing, and physically terrible.
My sleep had been difficult even during the lovely part of the trip, and now it's definitively wrecked!
Before planning any reset, let's talk what stress does to the body, what recovery can reverse, and where to start.
Speaking at so many conferences about bringing longevity into everyday care.
TL;DR
Short sleep affects focus, insulin response, and immune activity.
Recovery helps, but one good night may not be enough.
Start with a manageable routine. Use tests to answer a clear question.
What I keep hearing from clinicians
Longevity feels like it's everywhere. But clinicians are still wrapping their heads around what's real, what's hype, and what they can use in practice.
I spoke with hundreds of clinicians across my recent conferences, and several of my talks tackled that exact problem: what is ready for the clinic, and what might be used cautiously?
What I'm seeing more and more is frustration with half-answers. A test gives you a number. A product promises to improve it. But what are you actually supposed to do next?
Longevity also means meeting the patient where they are. We don't all want the same thing.
I'd be happy living as long as possible if I could still use a computer and hug my loved ones. My partner would rather look good and die at 70 😆.
Before choosing a test or treatment, I want to know what someone hopes to keep doing, what matters to them now, and what they're willing to take on to get there.
One of my talks was literally called Closing the Longevity Loop. Three ideas from it belong in your next health conversation:
1. Ready for what—and for whom? A treatment can help with a specific disease without being a proven way to slow aging. A test can measure something accurately without telling us how to improve it. Ask what the evidence supports for someone like you.
2. Cautious use needs a plan. If you and your clinician consider something with early evidence, agree on the goal, risks, what you'll track, and when you'll review it. Include what would make you stop. “Let's try it” leaves too much unanswered.
3. A result deserves a next step. What does it mean? Does anything need to change? Who will help, and when will you check again? Sometimes the answer is to leave things alone. You should still understand why.
I'm applying those same questions to my own wrecked sleep: what can I change, what will I track, and when should I get more help?
What being worn down means for your body
Travel, illness, an injury, and a demanding month can all leave us tired for different reasons.
Sleep loss is one common stressor, with well-studied effects:
Focus slips. In a 159-person study, five nights with four hours in bed impaired attention. And sad but true, even a ten-hour recovery night didn't fully restore attention.
Insulin works less well. Four nights with 4.5 hours in bed reduced insulin sensitivity by 23% in 19 healthy young men.
Immune activity shifts. In 14 adults, six weeks averaging 6.1 rather than 7.4 hours changed evening immune-cell counts and even how blood-forming cells regulate genes!
What can change back
Insulin sensitivity improved after two recovery nights averaging nearly ten hours in the 19-man study. But a different study in 15 men found incomplete recovery after two nights.
Some biological-age estimates fell during recovery, too. A study in humans and mice found that some scores rose during major stress and fell afterward. Human settings included surgery, pregnancy, and severe COVID-19; conference fatigue wasn't tested 😅.
Starting with recovery
My first goal is to feel and function better the next day.
1. Protect sleep. I'll keep a steady wake time, keep caffeine earlier, skip alcohol for now (bye bye Italian wine), and leave enough time to sleep.
2. Make room to recover. Fewer late commitments, an earlier stop to work, and regular meals with protein, carbs, and produce. No fasting either to compensate for vacation food.
3. Restart gently. If you're otherwise well, jump start exercise with walks or shorter, familiar workouts. Build as sleep, energy, and activity tolerance improve. Missed sessions don't need "making up."
Persistent insomnia may need cognitive behavioral therapy (CBT-I). With jet lag, light timing depends on your travel pattern.
After injury: follow your rehab plan. After an infection: if activity worsens symptoms 12–48 hours later, don't push through; ask your clinician about pacing.
Which tests and markers help?
Am I recovering? Track sleep, energy, focus, and how you feel after activity. If you use resting heart rate or heart-rate variability (HRV), compare your own trends (mine are the worst I've seen in a year, on both Apple Watch and Oura Ring!).
Why am I still tired? Sleeping enough but still exhausted? Check in with a clinician. Symptoms may call for a blood count and ferritin for anemia and iron status, thyroid tests, or a sleep-apnea assessment.
Has my age estimate changed? If you follow your biological age, try the same test method and note recent illness or poor sleep. Measurement error can change the score; a lower result doesn't prove slower aging.
Seek care for severe, worsening, or persistent fatigue that limits daily life. New chest pain, fainting, or marked breathlessness needs urgent care.
I want more swimming in my future. First, a few better nights.
Join me in Younger
I'm taking part in Younger 2027: baseline testing, six months to work on my habits, then retesting. Apparently, we've found a way to make going to bed earlier competitive.
The standard entry includes:
TruAge + TruHealth: at-home testing for biological-age and health-marker estimates, at baseline and retest. This is something I'll regularly use in my own patient population.
Brain and face: two rounds of NeuroGames cognitive testing and FaceAge estimates.
Function: a grip-strength tester and stopwatch. Participants also submit sit-to-stand videos and wearable VO₂ max estimates.
A digital Younger cookbook. For a handy reference, written by a neuroscientist and creator of this competition.
What I'm tracking alongside it:
Direct blood testing. TruHealth's markers are estimates from DNA methylation, so I also want conventional lab measurements.
Strength records in Hevy: tracking personal records (PRs), with weight and reps on the same lifts.
Wearable trends: heart rate, heart-rate variability (HRV), and, of course, my sleep.
Use CARECORE10 for 10% off.
NeuroAge provided my entry at no cost. I may earn a commission when you register with my code.
Until next time,
Hillary Lin, MD
From The Longevity Show
Dr. Mayoni and I discuss what we're seeing with peptides in practice—and why sleep, movement, and daily habits still come first.
⚡ Longevity quick hits
Sound during sleep improved recall in early Alzheimer's. A 37-person trial (preprint) found better overnight word-pair memory with timed sound than sham stimulation. One night; lasting benefits unknown.
Galleri won an FDA panel vote after a trial miss. The 142,250-person trial missed its main goal: fewer stage III/IV cancers combined across 12 types. Advisory support isn't FDA approval or proof of longer lives.
Liver injury worsened arthritis in mice. Disrupted selenium delivery linked the liver to cartilage damage. Selenium helped mice; benefit in people remains untested.
An experimental compound reversed paralysis in an MS mouse model. Kamuvudine-9 also reversed vision loss and preserved nerve insulation. Human benefit remains unproven.
Menopause-related proteins tracked with later brain health. Protein patterns differed even after accounting for age; higher scores linked to cognitive decline and dementia risk in older women. Association, not proof of cause.
A mouth bacterium had effects even after researchers killed it. Heat-killed Neisseria flavescens shifted molecular measures toward younger patterns in mice; live bacteria extended worm lifespan. Human rejuvenation remains unproven.
Where to find me
October 3, New York: I'm speaking at Her Longevity.
October 8, Boston: I'm joining the longevity medicine panel at the Translational Longevity Summit.
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