Estimates need context.

How to read data in the app

• Timelines concern consecutive time without smoking and restart after a cigarette; they do not describe the same effects for reduction alone.
• Percentages show progress between internal app milestones. They are not personal physiological measurements.
• Timing varies between people, and intermediate app milestones may sit within broader source ranges.
• SmettiAmo is not a medical device and this information does not replace medical advice.

Quitting and general recovery

1. World Health Organization — Tobacco: Health benefits of smoking cessation

   General timeline of changes after cessation, including heart rate, carbon monoxide, circulation, lung function and longer-term risks.

2. CDC — Benefits of Quitting Smoking

   Benefits over time, including blood nicotine, respiratory symptoms and risk reduction compared with continuing to smoke.

3. American Cancer Society — Health Benefits of Quitting Smoking Over Time

   Public timeline and general benefits, revised in 2025.

4. NHS Better Health — What could happen when you quit smoking

   Possible changes from the first day through later months, using language that recognises individual variation.

Cravings and withdrawal

1. National Cancer Institute — Tips for Coping with Nicotine Withdrawal and Triggers

   General symptom course, cravings, triggers and variation between people.

2. Smokefree.gov / NCI — Managing Nicotine Withdrawal

   Support for the first days and weeks, including the common difficulty of the first week.

Cardiovascular and respiratory estimates

1. CDC — Cigarettes and Cardiovascular Disease

   Cardiovascular risk reduction after cessation. Authoritative sources do not always use the same yearly threshold, so the app avoids a personal clinical percentage.

2. NHS Better Health — Benefits of quitting smoking

   Physical benefits, breathing, circulation and risk reduction. App milestones remain indicative.

Senses and short-term changes

Taste and smell information draws on the general WHO, NHS and American Cancer Society timelines listed above. The 7- and 14-day checkpoints are internal app milestones, not claims of complete clinical recovery.

Epidemiological life-time estimates

1. Jackson, Jarvis and West — The price of a cigarette: 20 minutes of life?

   Addiction, 2025. DOI 10.1111/add.16757; PubMed 39734064. This is a British population average, not a linear personal or clinical gain.

2. CDC — Very Low Nicotine Content Cigarettes

   Used to distinguish reduction from the greatest benefit of complete cessation. Reducing is not equivalent to the consecutive smoke-free timeline.

The motivational estimate uses population averages associated with the profile selected in the app; the unspecified value is an internal default. “Time without a cigarette in hand” instead uses an internal motivational model of about 5 minutes for each cigarette avoided.

The essential limit