Steam: Sauna Dose Calc

Pay once. No subscription, no ads, no account. Works offline.

Steam is the iOS calculator, citation reference, and session log for sauna users. Tell Steam your planned duration and what type of sauna you use; Steam matches your week-to-date frequency and your planned session length to the Laukkanen KIHD-cohort dose-response framework, surfaces the hazard ratios reported at each tier with PubMed PMID anchors, and logs the session for cumulative tracking.

Not a medical device. Steam does not diagnose, treat, or cure any condition. It is a calculator, a citation reference, and a session log. Hazard ratios shown in the app are reported as observational findings from the named cohort — never as personalized risk-reduction guarantees.

Why named-source citations matter: sauna wellness apps tend to invent thresholds and call them "release zones." Steam ties every threshold to a primary publication you can verify yourself. Frequency tiers are cited to Laukkanen, Khan, Zaccardi, Laukkanen 2015 JAMA Internal Medicine, PMID 25705824 (KIHD n=2315 Finnish men, 20.7-year follow-up). Dementia tiers are cited to Laukkanen, Kunutsor, Kauhanen, Laukkanen 2017 Age & Ageing (same KIHD cohort). The mixed-sex extension is cited to Laukkanen, Laukkanen, Khan, Babar, Kunutsor 2018 BMC Medicine, PMID 30486813. The synthesis paper at Mayo Clinic Proceedings 93(8):1111-1121 is the single-paper entry point.

Features
• This-week frequency tier: 1 / 2–3 / 4–7 sessions per week, with the highest tier's hazard ratios shown vs the 1-session-per-week baseline
• Per-session duration tier: under 11 / 11–19 / ≥19 minutes, with the highest tier's hazard ratios shown vs the under 11 minute baseline
• Multi-session log with cumulative this-week count + total minutes
• Sauna type selector: Finnish (Laukkanen primary), Infrared (with explicit evidence-gap caveat — infrared was not in the KIHD cohort), Steam room (with caveat — distinct from sauna proper)
• Citations & Sources screen with PMID links, cohort-size attribution, and the comparison-baseline disclosure on every hazard ratio
• Cardiovascular safety acknowledgement on first launch, citing Laukkanen et al. 2018 Mayo Clinic Proceedings § Safety considerations
• Universal app for iPhone and iPad

Cardiovascular safety: sauna is contraindicated for unstable cardiovascular conditions, recent myocardial infarction, severe untreated hypertension, and orthostatic hypotension. Pregnancy requires clinician sign-off. Alcohol pre-session increases sudden cardiac death risk per Laukkanen, Laukkanen, & Kunutsor 2018, Mayo Clinic Proceedings § Safety considerations. Steam surfaces this on first launch and keeps the caveat in the Sources tab.

Privacy: Steam collects nothing. No analytics, no accounts, no network requests, no Bluetooth, no HealthKit. Your sessions live on your device.

Like calculators with citations? Look up Frost (cold plunge), Lumen (red light), Watt (solar for van and RV), and Strip (USDA jerky safety) by the same developer.