Nicotine · sleep · iPhone
Track Nicotine Pouches Against Your Own REM Sleep
Circa logs pouches by count or by milligram, carries the decay curve to your bedtime, and compares the nights you used nicotine after 20:00 with the nights you did not. It is a measuring instrument, not a quit programme.
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Logging
Pouches, in the unit you think in
Nicotine pouches are sold by strength, and people count them by pouch. Circa handles both. Log two pouches and the app converts them to a milligram equivalent so the curve and the statistics have something numeric to work with, or type the milligrams directly when you know them. Quick chips cover the common strengths.
From there it behaves like the caffeine side: a decay curve running to your bedtime, the total for the day, and the amount projected to still be with you when you go to bed.
The 20:00 line
Late nicotine is a separate variable
Circa treats any nicotine logged from 20:00 onwards as late nicotine, and that is not cosmetic. Late nicotine is its own input in two places.
In tonight's forecast
The driver model applies a signed penalty to predicted deep-sleep minutes when late nicotine is on the board, and shows that contribution as its own line rather than folding it into a single score.
In the audited comparison
Circa splits your complete nights into two groups, the ones with nicotine after 20:00 and the ones without, and compares the REM minutes your tracker recorded between them. The result is reported as a difference with a 95 percent confidence interval and a p-value, with the group sizes on show.
Group comparisons on small samples produce wide intervals, and Circa says so on the card rather than rounding the uncertainty away. The physiology reference the app cites here is Zhang et al., Am J Epidemiol 2006, on smoking and nocturnal sleep architecture.
Honesty
Circa is not a quit app
This matters enough to put in its own section, because the search that brings people here is usually about quitting.
- No quit plan, no taper, no streaks. There is no target, no countdown and no badge for a clean day.
- No craving support. No panic button, no trigger log, no coaching, no community.
- No notifications. Circa will never prompt you about anything.
- What it does instead is show you the cost side in numbers you can check: the curve, the forecast penalty, and the REM comparison across your own nights.
If you want to stop, a dedicated quit app will serve you far better, and several good ones exist. If you want to know what the pouch at 22:00 is doing to your sleep architecture, that is the question Circa was built for.
Circa is a personal tracking tool, not a medical device. It does not diagnose, treat, or prevent any condition, and it gives no medical advice. Its numbers describe your own logs and your own tracker readings, nothing more. Talk to a qualified professional before you change medication, supplementation, or anything else about your health.
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