Vitamin D, 25-hydroxy (25-OH vitamin D)

Pick Ordered or Not ordered to see the note.

Indicated when

• —Osteoporosis, osteopenia, rickets, malabsorption syndromes, chronic kidney disease, or use of a medication that affects vitamin D metabolism: the conditions Ontario recognizes as insured indications [2]
• —Investigating confirmed or strongly suspected metabolic bone disease, unexplained hypercalcemia or hypocalcemia, or unexplained elevated parathyroid hormone, per Ontario laboratory guidance [4]

Not indicated when

• —Routine screening of a healthy, asymptomatic adult with no risk factor, including as part of a general wellness panel [1, 5]
• —Screening a general population group, including people with obesity or darker skin pigmentation, who were flagged for testing in older guidance but are not in the 2024 Endocrine Society guideline [5]
• —Confirming adequacy before or during empiric vitamin D supplementation at standard doses in an otherwise healthy adult under 75 [5]

Why not

The 2024 Endocrine Society guideline panel found no clinical trial evidence to support routine 25(OH)D testing in any population it considered, including people with obesity or darker skin, and could not identify a clear target level that testing would aim for [5]. The 2021 USPSTF review similarly concluded the evidence is insufficient to weigh the benefits and harms of screening asymptomatic adults, so a result outside a lab's reference range does not reliably predict who benefits from treatment [6]. Testing without a clear indication mainly adds cost and can prompt repeat testing on an assay whose reference ranges and cut-offs are not uniformly standardized.

Better first step

For a healthy, nonpregnant adult under 75 with a general concern about vitamin D intake, the 2024 Endocrine Society guideline itself points toward empiric supplementation at the standard recommended dose rather than testing first; testing is for the specific indications above [5].

Typical ND rationale

An ND may order 25-hydroxy vitamin D routinely for patients with fatigue, low mood, frequent infections, or musculoskeletal pain, reasoning that vitamin D deficiency is common in Canada, especially over winter, is easy to correct, and that a level lets dosing be individualized rather than guessed.

Ontario coverage & CONO orderability

OHIP status

insured_conditional

L606 25-hydroxy vitamin D is insured only for persons with osteoporosis, rickets, osteopenia, malabsorption syndromes, renal disease, or on medications that affect vitamin D metabolism [2]. Outside those conditions it is not an insured service; physicians must mark it uninsured. Insured only when ordered by a physician, midwife, or NP who has clinically assessed the patient (Reg. 552 s.22); the same test ordered by a naturopathic doctor is not insured and is billed privately regardless of indication [9].

CONO orderable

Yes — CONO list #131

CONO list item 131, blood: 'Vitamin D, 25-hydroxy.'

Linked conditions

• Vitamin D deficiency ↗
• tired ↗

Counselling script

“For most healthy adults, current guidelines advise against routine vitamin D testing, because the result rarely changes what we'd recommend. If you have a bone condition, a gut condition affecting absorption, kidney disease, or take a medication that affects vitamin D, that's a real reason to check it, and I'm happy to order it.”

Revisit if

• —New diagnosis of osteoporosis, osteopenia, rickets, or a malabsorption syndrome
• —New chronic kidney disease diagnosis
• —Starting a medication that affects vitamin D metabolism

References

1. [1]College of Family Physicians of Canada / Choosing Wisely Canada (2026). Family Medicine: Fifteen Tests and Treatments to Question. linkDon't routinely measure vitamin D in low-risk adults
2. [2]Ontario Ministry of Health (2026). Ontario Health Insurance Plan: Schedule of Benefits for Laboratory Services (effective April 1, 2026). link25-hydroxy vitamin D is insured only for osteoporosis, rickets, osteopenia, malabsorption syndromes, renal disease, or medications affecting vitamin D metabolism
3. [3]Ontario Health Technology Advisory Committee (OHTAC) (2010). OHTAC Recommendation: Clinical Utility of Vitamin D Testing. linkolder guidelineOHTAC does not recommend routine vitamin D testing
4. [4]Ontario Association of Medical Laboratories (OAML) (2010). Guideline for the Appropriate Ordering of Serum Tests for 25-hydroxy Vitamin D and 1,25-dihydroxy Vitamin D (CLP026). linkolder guidelineOntario laboratory guidance on when 25-hydroxy vitamin D testing is and is not indicated
5. [5]Endocrine Society (2024). Vitamin D for the Prevention of Disease: An Endocrine Society Clinical Practice Guideline. linkThe Endocrine Society panel found no clinical trial evidence to support routine 25(OH)D testing in any population considered, including obesity or dark complexion, and suggests against routine testing
6. [6]US Preventive Services Task Force (2021). Screening for Vitamin D Deficiency in Adults: US Preventive Services Task Force Recommendation Statement. linkCurrent evidence is insufficient to assess the balance of benefits and harms of screening for vitamin D deficiency in asymptomatic adults
7. [7]Ontario Ministry of Health (2026). Ontario Health Insurance Plan: Schedule of Benefits for Laboratory Services (effective April 1, 2026). linkCommunity lab tests are insured only when ordered under the Schedule by an authorized prescriber
8. [8]Government of Ontario (e-Laws) (2026). Health Insurance Act, R.R.O. 1990, Reg. 552: General, s. 22 (insured laboratory services). linkA lab test is insured only when ordered by a physician, midwife, or NP who has clinically assessed the patient
9. [9]Ontario Ministry of Health (2026). Ontario Health Insurance Plan: Schedule of Benefits for Laboratory Services (effective April 1, 2026). linkTests ordered by anyone other than an authorized provider, including NDs, are not insured services