How Apple Health Metrics Become the MyBioAge Index™
Follow the path from Apple Health readings to My Bio Age’s weekly wellness estimate, including aggregation, data coverage and optional inputs.
By My Bio Age
The MyBioAge Index™ turns available Apple Health measurements into a weekly biological age estimate for wellness tracking. It is a model built from selected signals, not a direct measurement of the age of your cells.
Start with the source records
The app reads the Health categories you allow. These may be supplied by Apple Watch, other compatible devices or entries in Apple Health. The app cannot create a missing sensor measurement just because you have granted permission.
On first use, My Bio Age loads recent data and then the six-month Index window. Versions with extended history also import older available records into a local coach archive, resuming after interruptions. Later refreshes retrieve recent changes. What you see depends on the records present, permissions and coverage.
Complete weeks make up the Index
The weekly pipeline aggregates complete Monday-to-Sunday periods and can retain up to 24 weeks of Index results. It combines the available metric values with the model’s reference information and confidence assessment. The incomplete current week is not scored.
Which inputs contribute?
The core model has 12 weighted metrics, with systolic and diastolic blood pressure available as two additional inputs. These include fitness, cardiovascular, sleep, activity and derived recovery measurements. Stress Resilience and Circadian Alignment are separate daily scores, not additional weighted Index inputs.
Some underlying data are shared across features. That does not mean every dashboard number is added into the Index. Each feature has its own purpose, window and data requirements.
What confidence means
Confidence describes aspects of the available data and model coverage. It is not the probability that the biological age estimate is medically correct. When critical inputs or coverage are insufficient, the app can show a limited result and withhold comparisons.
Use the model as a starting point
A change in the Index should prompt a look at the contributing measurements. Source changes, missing weeks, settings changes and app updates can affect comparability. A falling estimate is not proof of longer life, and an increasing estimate is not a diagnosis.
All Index calculations run locally on your iPhone. Your health data is not sent to a clinical partner to calculate the score. For the distinction between the weekly estimate and daily Recovery or Training Load, review the relevant detail view rather than assuming every feature updates in the same way.
Explore what your existing Apple Health records contribute to a complete weekly picture. Download My Bio Age free on the App Store. The iPhone app is completely free, with no in-app purchases, subscription or account required. Your health data is processed privately on your iPhone, and optional AI answers run fully on device after a model download.