What intermittent fasting means
Intermittent fasting describes eating patterns that alternate between periods of eating and periods with no or very little food. It is an umbrella term, not one fixed program. Daily time-restricted eating, alternate-day fasting, and the 5:2 pattern all fit under it, but they ask different things of a person and are studied separately.
Pause focuses on time-restricted eating: choosing a daily eating window and tracking the time outside it. A 16:8 schedule, for example, has a sixteen-hour fasting period and an eight-hour eating window. It describes when food is eaten, not which foods belong on the plate.
Common daily schedules
A wider window such as 13:11 is often easier to fit around existing meals. A 16:8 schedule commonly keeps two meals inside an eight-hour window. The narrower 18:6 and 20:4 schedules leave less room for late meals or changes of plan. A 36-hour fast is not simply a tighter daily window and deserves additional caution.
See the schedule comparison for how the windows differ, or read the focused 16:8 guide.
What the evidence can and cannot say
Research on intermittent fasting includes several different eating patterns, study lengths, and participant groups. Recent systematic reviews report changes in some weight and cardiometabolic measures, but results vary by strategy and are often compared with continuous calorie restriction. That does not establish that one schedule is best for everyone or that benefits will persist long term.
The National Institute on Aging notes that much of the human evidence is short term and that researchers still need better evidence about long-term safety, feasibility, and effects across different groups. Treat confident universal promises as a warning sign.
When to ask for medical guidance
Speak with a qualified healthcare professional before fasting if you are pregnant or breastfeeding, take medication affected by meal timing, have diabetes or another medical condition, are underweight, or have a current or previous eating disorder. Children and teenagers should not use a general wellness app to make this decision.
Stop a fast if you feel unwell. A timer records time; it cannot assess symptoms, nutritional needs, medication risk, or whether fasting is appropriate for you.
Where tracking fits
A fasting tracker can remember a start time, show the remaining time, and keep a history. It can also keep optional water and weight records together. These are record-keeping tools, not evidence that a routine is safe or effective.
Pause provides a fasting timer for iPhone, Home Screen and Lock Screen widgets, a Live Activity, optional Apple Health connections, and offline-first storage. You start and end every fast yourself, and the app does not prescribe a schedule or tell you what to eat.