This population-scale atlas provides the first comprehensive description of real-world medication and dietary supplement timing, suggesting that temporal adherence may be considered an important dimension of medication-taking behavior.
Key Findings
Results
Medication use exhibited daily patterns, with most therapeutic classes following one of two dominant patterns: morning- or evening-predominant intake.
Analysis was based on more than 200,000 intake events from 26,069 adults
Data were collected via time-stamped records from the myCircadianClock smartphone application
The two dominant patterns (morning and evening) were observed consistently across therapeutic classes
This represents a population-scale atlas of real-world intake timing
Results
Dietary supplements displayed four distinct temporal patterns, compared to only two for medications.
The four supplement patterns largely corresponded to morning, meal-associated, or bedtime use
This contrasts with medications, which showed predominantly two patterns (morning or evening)
The greater variety of supplement timing patterns suggests more flexibility or user-driven scheduling in supplement intake
Results
Medication timing was highly consistent across age and sex, although the types of medications consumed varied substantially with age.
Despite demographic differences in which medications were used, the temporal patterns of intake were stable across age groups and between sexes
The consistency in timing across demographics suggests population-level behavioral norms around medication-taking schedules
Variation in medication types by age reflects expected differences in health conditions and treatment needs across the lifespan
Results
While the timing of many medications aligned with general chronotherapy recommendations, every therapeutic class exhibited considerable variability in intake timing.
A substantial proportion of intake events occurred several hours outside the predominant intake window for every therapeutic class examined
This variability was observed even for drug classes where timing is known to influence therapeutic efficacy and adverse effects
The findings indicate that real-world timing adherence is imperfect across all medication categories
Methods
The study generated the first comprehensive population-scale atlas of real-world medication and dietary supplement timing.
The dataset included 26,069 adults enrolled in the myCircadianClock smartphone application
More than 200,000 intake events were analyzed
Over 200 therapeutic classes were represented in the dataset
The atlas characterizes temporal patterns at the population level, providing a baseline for future chronotherapy research
What This Means
This research suggests that when people take their medications and supplements follows predictable daily patterns at the population level. Using data from over 26,000 adults who logged their medication and supplement use through a smartphone app, researchers found that most medications tend to be taken either in the morning or in the evening, depending on the drug type. Dietary supplements showed more variety, with four distinct timing patterns that generally corresponded to morning, mealtime, or bedtime use. These patterns were remarkably consistent regardless of a person's age or sex, even though older and younger people tended to use different types of medications.
However, the research also found that even when a medication class has a clear 'typical' time of use, a large portion of people take that medication several hours outside that typical window. This matters because research in the field of chronotherapy — the study of how timing affects drug effectiveness — has shown that when you take a medication can influence how well it works and what side effects it causes. The fact that real-world timing varies so widely from recommended patterns suggests there may be an underappreciated gap between clinical guidelines and everyday practice.
This research suggests that 'temporal adherence' — not just whether someone takes their medication, but when they take it — could be an important factor in understanding how well treatments work in the real world. The dataset represents the first large-scale, real-world map of medication and supplement timing and could serve as a foundation for future studies examining links between intake timing and health outcomes.
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Tran T, Varshney S, Rosmalen L, Levy J, Laing K, Manoogian E, et al.. (2026). Daily Patterns in the Timing of Medication and Supplement Intake.. Nutrients. https://doi.org/10.3390/nu18193291