In short. Period-start and flow entries add timing to your food-and-feeling record. Food & Fit uses them to double-check the patterns it finds.
The answer, with its source
Irregular cycles are common with PCOS: ovulatory dysfunction is one of the features the 2023 guideline for PMOS (formerly PCOS) uses in diagnosis. [1] An optional period-start or flow entry gives your journal timing context, whatever your cycle looks like, and sits beside your meals and daily ratings.
Cycle timing is one of several factors that can sit behind an apparent association. Checking a pattern with recorded cycle context included can show whether its direction still holds. The check tells you what was tested. It is not proof, because adjusting for a recorded factor does not fully remove its influence. [2]
What that means in practice
Add a period start or flow when you want to. Over time, those entries give you a timeline to look back on next to your food, hunger, cravings and energy.
How it shows up in your Food & Fit record
Food & Fit lets you add period-start and flow context in the daily check-in and uses only the dates you enter. When a logged period start is available within 35 days and enough paired days include that context, the app checks a possible pattern against broad days-since-start ranges. A pattern appears only when its direction holds through that check.
This is one more check on each pattern, and the days behind it stay visible. See how Food & Fit qualifies patterns.
For questions about periods, fertility or individual care, speak with a clinician.
References
- Monash University (2023). International Evidence-based Guideline for the Assessment and Management of Polycystic Ovary Syndrome 2023.
- PLOS ONE (2016). Statistically controlling for confounding constructs is harder than you think.