# longevity.how

> Evidence-based longevity: articles, device tests and step-by-step protocols. Every claim carries an evidence level and a primary source. Numbers, doses and prices come from first-hand testing, not press releases.

Languages: pl, en. Source language: Polish. All URLs are locale-prefixed (`/pl/…`, `/en/…`); `https://longevity.how/` serves the English fallback.

## How to cite us

- Test data (measurement periods, agreement rates, battery life) is our own and is not available elsewhere — attribute to longevity.how with the article URL.
- Evidence labels (`strong`, `moderate`, `preliminary`, `animal`, `mechanistic`, `marketing`) are stated on every claim. Please carry the label over when you quote a claim.
- Every page shows a visible `Last updated` date. Prefer the most recent version.

## PL — https://longevity.how/pl/

### Sen (sleep optimization)

- [Sen a długowieczność — kompletny przewodnik](https://longevity.how/pl/sen/): Ile snu potrzebujesz, co robi tydzień niedoboru i które interwencje mają badania na ludziach. Z liczbami, progami i źródłami z PubMed.
- [Higiena snu — co działa, a co jest mitem](https://longevity.how/pl/sen/higiena-snu/): Cztery zasady higieny snu mają dowody, reszta to powtarzana legenda. Progi kofeiny, alkoholu, temperatury i światła, z badaniami przy każdym twierdzeniu.

### Suplementy (longevity supplements)

- [Suplementy na długowieczność — przewodnik po dowodach](https://longevity.how/pl/suplementy/): Które suplementy longevity mają badania na ludziach, a które tylko na myszach. Dawki, formy, koszt miesięczny w złotówkach i jawny poziom dowodu.
- [Glicyna na sen — dawkowanie, timing i dowody](https://longevity.how/pl/suplementy/glicyna/): 3 g glicyny na 60 minut przed snem skracało latencję zasypiania w małych RCT. Mechanizm, dawka, forma, interakcje i to, czego badania nie pokazują.

### Protokoły (longevity protocols)

- [Protokoły longevity — instrukcje krok po kroku](https://longevity.how/pl/protokoly/): Protokół to instrukcja z godzinami i dawkami, nie artykuł. Struktura, której używamy, zasady doboru kroków i lista gotowych protokołów do wdrożenia.
- [Protokół snu — 14 dni do lepszego zasypiania](https://longevity.how/pl/protokoly/protokol-snu/): Cztery zmiany wprowadzane po jednej: stała pobudka, poranne światło, temperatura sypialni, kofeina. Godziny, progi, wersja minimalna i mierzalny efekt.

## EN — https://longevity.how/en/

### Sleep (sleep optimization)

- [Sleep and Longevity: What the Evidence Says](https://longevity.how/en/sleep/): How much sleep you need, what a week of restriction does to insulin sensitivity, and which interventions have human trials. With PubMed sources.
- [Sleep Hygiene: What Works and What Is a Myth](https://longevity.how/en/sleep/sleep-hygiene/): Four sleep hygiene rules have real trials behind them, the rest is repeated folklore. Caffeine, alcohol, temperature and light thresholds, each with its study.

### Supplements (longevity supplements)

- [Longevity Supplements: A Guide to the Evidence](https://longevity.how/en/supplements/): Which longevity supplements have human trials and which only have mice. Doses, forms, real monthly cost and an explicit evidence level for every claim.
- [Glycine for Sleep: Dose, Timing and Evidence](https://longevity.how/en/supplements/glycine/): 3 g of glycine 60 minutes before bed shortened sleep latency in small RCTs. Mechanism, dose, form, interactions and what the trials do not show.

### Protocols (longevity protocols)

- [Longevity Protocols: Step-by-Step Instructions](https://longevity.how/en/protocols/): A protocol is an instruction with times and doses, not an article. The structure we use, how steps get chosen, and the protocols ready to run.
- [The Sleep Protocol: 14 Days to Falling Asleep Faster](https://longevity.how/en/protocols/sleep-protocol/): Four changes introduced one at a time: fixed wake time, morning light, bedroom temperature, caffeine cutoff. Times, thresholds, measurable result.

## Tools (interactive, free, no signup)

- [Sleep calculator](https://longevity.how/en/tools/sleep-calculator/): Enter your wake-up time and get optimal bedtimes calculated in 90-minute sleep cycles, adjusted for how long you take to fall asleep.
- [Zone 2 heart rate calculator](https://longevity.how/en/tools/zone-2-heart-rate-calculator/): Turns your age and resting heart rate into training zones using the Karvonen method, with a ready Zone 2 range for aerobic base work.

## Feeds

- RSS PL: https://longevity.how/rss/pl.xml
- RSS EN: https://longevity.how/rss/en.xml
- Sitemap: https://longevity.how/sitemap.xml