# Deep Sleep (Slow-Wave Sleep)

To get more deep sleep (N3), the levers that actually work are behavioral and environmental, not pills: keep your bedroom at 17 to 20°C with warm feet, take a hot bath (40 to 43°C) one to two hours before bed, exercise aerobically in the evening, hold a fixed sleep schedule, and cut alcohol within three hours of bed. No supplement has sleep-lab evidence of meaningfully deepening deep sleep in healthy adults; glycine (3g) gets you there faster without adding more, and most "deep sleep" supplement claims come from wearables, not brain waves.

The slice of sleep that matters most as you age. What actually lifts it, and the honest truth about supplements.

## On this page

- What Is Deep Sleep (N3), Exactly?
- Why Does Slow-Wave Sleep Matter for Longevity?
- Why Does Deep Sleep Disappear With Age?
- How Do You Actually Measure SWS at Home?
- Which Behavioral Levers Actually Increase SWS?
- How Does Temperature Change Your Deep Sleep?
- Do Supplements Actually Deepen Deep Sleep?
- Do Magnesium Bisglycinate and Glycine Deepen Sleep?
- Does Lemon Verbena Plus Zinc Boost Deep Sleep?
- Do L-Theanine, Saffron, and Taurine Deepen Sleep?
- What to Avoid: Alcohol, Z-Drugs, High-Dose Melatonin
- What Is the Honest Deep-Sleep Protocol?

## FAQ

- How much deep sleep do I actually need?
- My Oura ring says I only get 30 minutes of deep sleep. Should I be worried?
- Does magnesium bisglycinate really give me more deep sleep?
- What about Magnesium L-threonate / Magtein for deep sleep?
- Can I really increase deep sleep with a cooling mattress?
- Will closed-loop auditory stimulation deepen my sleep?
- Is there a pill that genuinely deepens slow-wave sleep?
- Why does my deep sleep crash when I drink wine with dinner?

## Sources

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_Full guide: https://longevity-germany.com/en/guide/deep-sleep_

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_Canonical: https://longevity-germany.com/en/guide/deep-sleep · Part of Longevity Cities · Updated 2026-06-22_