reproductive · Outcome
Bring cycles back into a predictable rhythm.
How to measure:
Three levers, one stack. Each works through a different mechanism. They compound.
+79% regularity
2000-5000 IU daily
Evidence
Effect size
Corpus
12 papers
range 78–80 · n=2 quantitative claims
“25-hydroxyvitamin D insufficiency (<30 ng/ml) was associated with increased risk of generalized aches and pains in women with regular menstrual cycles.”
Noticeable
45-120 min, 3-4x per week
Evidence
Effect size
Corpus
4 papers
1 small · 8 moderate · 1 large · 2 unclear
No corpus-backed pick yet
We require at least 3 corpus papers for a food to surface here. The literature on this outcome × pillar is still being extracted.
Everything we found, ranked by how strongly we recommend it. Tap any to see the studies.
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Every pick has two signals. They answer different questions and we never bundle them into one number.
Effect size
How big is the change on cycle regularity, in the units that matter for this outcome.
Confidence
How sure are we the effect is real for cycle regularity, given the studies we have.
For every pick, the “papers” number is how many studies we've cataloged that test this entity for cycle regularity. “Favorable” means the study reported the direction you want.
The tier badge (S, A, B…) on the entity itself is its overall research confidence across all outcomes. It's the same letter wherever you see this entity on the site, not specific to cycle regularity.
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“Strength loss following exercise is greater during the early follicular phase compared to the midluteal phase of the menstrual cycle.”