Get Ahead of Aging, by Rebuilding Your Sleep First.

How you sleep is tied to memory, mood, blood pressure, blood sugar, and whether you can show up for the people and activities that matter to you. For years, though, the tools we’ve had to measure sleep and long-term health risk have been fairly blunt: “how many hours,” questionnaires, or a diagnosis like sleep apnea.Now something new is arriving: large AI models that look at every second of your sleep study and try to map that pattern to future health. One of the latest examples is the 2026 project, SleepFM—developed by a multi-institution collaboration including researchers at Stanford & Harvard.SleepFM is a “foundation model” trained on more than half a million hours of clinical polysomnography (full overnight sleep studies with EEG, breathing, heart rhythm, and more).From one overnight sleep study, it can estimate risk for conditions ranging from dementia to heart failure and all-cause mortality.At the same time, other human studies are sharpening the picture of which features of sleep matter most in later life: how much deep slow-wave sleep you get, how stable your emotional brain feels after sleep, and how “old” or “young” your brain looks.In this article, we’ll cover:How the 2026 SleepFM study uses one overnight sleep study to predict risk for about 130 conditions, including dementia and cardiovascular disease.What new work in older adults shows about deep non-REM slow-wave sleep and anxiety, and why that matters for brain aging..How slow-wave sleep loss over years relates to your chance of developing dementia in late life.How deep-learning models that estimate your “sleep age” from overnight studies connect to life expectancy.All of this will stay grounded in what you can actually do with this knowledge: how to think about getting a sleep study, how to protect the parts of sleep that seem most tightly linked to brain and heart health, and how to view these new AI tools in a measured helpful way.Let’s get started.

Autonomic sleep disruption occurs when the body’s involuntary regulation — heart rate, stress hormones, and neural inhibition — fails to transition properly into sleep mode. Three mechanisms drive it:Weakened vagal tone — parasympathetic activation doesn’t engage at sleep onset, leaving heart rate elevated through the night Reduced GABA — the brain’s primary inhibitory neurotransmitter is insufficient, preventing entry into deep sleep Overactive HPA axis — cortisol surges too early, producing the characteristic 2-3am wakeup with a racing mind Chronic stress, neuroinflammation, gut microbiome disruption, and hormonal changes can each weaken these pathways. The hallmark experience is waking up alert — not groggy — often with a racing heart or the “wired but tired” feeling. Heart rate variability during sleep and cortisol patterns are measurable indicators.

Alcohol does increase deep non-REM sleep in the first few hours of the night. Studies show deep sleep running higher in that early window — you fall asleep faster, sleep looks more continuous.

Sleep and the gut.Two areas of longevity science I keep coming back to — both in my own work and in my own health. I think the gut-sleep connection is one of the more underappreciated intersections in health, and it’s something I’ve wanted to explore in a focused conversation for a while.Today I get to do that — through a written Q&A with Scott C. Anderson.Scott is a science journalist and co-author of The Psychobiotic Revolution: Mood, Food, and the New Science of the Gut-Brain Connection — a National Geographic bestseller he wrote alongside John F. Cryan and Ted Dinan, the researchers who coined the term psychobiotics. He also writes on Substack about the gut-brain connection.I asked Scott six questions about the gut-brain axis, cortisol, probiotics, and what the research says about improving sleep through the microbiome.Here’s what he had to say:

If We Rely on “Normal” Lab Ranges, We’ll Miss the First Signs of Decline.

Waking to urinate once or twice overnight sits within the range of normal kidney physiology — kidneys have their own circadian rhythm, and their activity reduces during sleep, but they don’t stop. The challenge is when waking to urinate becomes a disruption in itself: the peeing happens, and then sleep doesn’t return. That’s a different kind of problem than urination frequency alone. There are multiple explanations for this pattern, and they don’t all lead to the same place. Some are best ruled out with a physician — there are medical causes that are important to consider. Others trace back to sleep itself. And the details — when it happens, how consistently — tend to matter in distinguishing between them. Here are 3 reasons you might be waking up to pee at night, how to distinguish between them, and what to do so you can stay asleep through the night: