Study Finds Little Evidence That Menstrual Tracking Apps Improve Health or Performance

Menstrual tracking apps and other digital "femtech" tools may create risks without providing the health benefits they claim, according to experts writing in The BMJ.

These technologies are widely promoted to women and girls through social media and technology companies. They claim to analyse personal menstrual cycle data to provide insights into health, wellbeing, exercise and nutrition.

However, experts say there is limited evidence that menstrual tracking or “cycle syncing” improves health or physical performance. Cycle syncing involves changing diet or exercise according to different phases of the menstrual cycle.

Decades of sports science research have found no consistent overall effect of menstrual cycle phase on exercise performance, injury risk or health. Where associations have been reported, they tend to be small and highly individualised. Evidence for diet plans based on menstrual phases is also generally inconclusive or speculative.

Experts also point out that even if an individual's health or performance changes during different menstrual phases, basic digital tracking tools cannot reliably predict these changes.

Beyond the limited evidence, researchers highlight several concerns surrounding digital menstrual tracking. These include privacy risks involving sensitive health data, unwanted surveillance and the time and effort required to regularly record information. Such technologies could also divert attention from broader efforts to address women's health needs.

Experts recommend stronger protections for consumer and workplace health data and greater awareness among users about how menstrual information may be collected, stored and used. They also suggest that healthcare professionals recommend tracking apps only when they meet appropriate standards for privacy, evidence and safety.

Overall, they say menstrual tracking technologies should not be treated as scientifically proven tools for improving health or performance. Greater regulation, evidence-based guidance and critical evaluation are needed to ensure these technologies do not create additional risks for women and girls.

REFERENCE: Lee, K. M. N., et al. (2026). Digital menstrual tracking risks creating more harm than benefit. BMJ. DOI: 10.1136/bmj-2026-100858.