Dietary Vitamin D

  • Unitmcg
  • SinceiOS 8.0 (2014)
  • KindQuantity

By PulsHealth. Updated

Research reviewed .

What does Apple Health dietary vitamin D measure?

Dietary Vitamin D records an amount attributed to food or supplements. Apple defines it as a cumulative mass quantity. This page uses mcg for display. It records intake contributions rather than continuously measuring the body. A record may describe one food, one supplement or a source's daily total.

How do dietary vitamin D, IU and daylight differ?

Vitamin D supports calcium absorption and bone health. Dietary records can include food, fortified products and supplements. Standard vitamin D labels use 1 microgram = 40 IU, as explained by NIH ODS. Use that relationship to check a label, rather than treating IU as a generic HealthKit mass unit. A correct conversion still needs a correct serving size.

QuantityWhat it represents
Dietary vitamin D, mcgAmount recorded from foods or supplements
D2 or D3Form that needs a label or source description
Time in Daylight, minutesRecorded daylight exposure, not a vitamin D dose
Serum 25-hydroxyvitamin DLaboratory concentration, not logged intake

Sunlight can contribute to vitamin D production, but daylight duration alone cannot quantify it. Dietary intake also cannot be converted into a serum level. The unit field does not identify D2, D3 or how much was absorbed.

How should portions and unusual amounts be checked?

First identify the record's scope: a serving, a whole package or a daily summary. Inspect the source, unit and food description before combining amounts. The same meal imported through two apps can appear twice. A large entry may reflect a supplement, a portion multiplier or a unit error; its size alone cannot establish excessive intake or toxicity.

Intake reference values apply to a defined population and daily intake basis. They are not a physiological range for arbitrary sample amounts. Incomplete logs and unknown nutrient-form conversions make those comparisons especially uncertain.

Do timestamps identify when a meal was eaten?

Gaps between records describe logging or synchronization behavior. They do not establish meal timing, digestion or absorption. A cluster can come from retrospective logging, while a midnight timestamp may represent a day summary.

Comparisons with other nutrient types require compatible sources, portions and reporting-day coverage. Missing records remain unknown intake.

What did the database investigation support?

The investigated 365-day reporting window contained no raw vitamin D samples or stored aggregates for this type. Value ranges, extreme portions, source distributions, logging intervals and time-of-day patterns were unavailable. Relationships with other types could not be measured without vitamin D observations. No measured chart is presented.

These vitamin types are documented in the knowledge base but are not collected by the current PulsHealth sync catalog. Database absence therefore does not establish whether the phone's Apple Health store contains these records, or imply zero consumption or deficiency.

How can I make these records easier to interpret?

Use a consistent food database, confirm serving sizes and include supplements explicitly. Check whether imported totals contain individual food entries already recorded elsewhere. Summarize compatible contributions by source and reporting day, and show days with logs separately from recorded amounts.

Apple's nutrition documentation allows selected nutrient types to be recorded, so a calorie entry does not guarantee a vitamin D entry. Review contributing sources when changing nutrition apps. Optional food descriptions may help, but a matching timestamp does not prove membership in a HealthKit Food correlation.

Understanding your records

Recording frequency, source and coverage affect what you can conclude from this data. Read the recording guide.

One record
Cumulative recorded nutrient mass; sample scope may be a serving, supplement or source summary.
Frequency
Source-specific logging or synchronization; no documented fixed sampling frequency or confirmed meal schedule.
Context
Check the recorded amount and label units for food or supplements before combining entries from different sources.
Coverage and gaps
Missing records do not establish zero intake; sources may record only selected nutrients.
Summaries
Sum compatible contributions within a source and reporting window after checking units, portions, chemical-form basis and duplicate imports. State logged-day coverage.
Metadata
Optional food descriptions may help inspect portions and chemical forms but cannot supply missing form information or correlation linkage.

Recording guidance reviewed 2026-10-14

Technical details
IdentifierHKQuantityTypeIdentifierDietaryVitaminD
SourceHealthKit
Aggregationcumulative
Availability
iOS 8.0 (2014)
watchOS 2.0 (2015)
Last updated: 2026-10-14

Related Metrics