Monthly supplements of vitamin D did not alter the incidence of hypertension, hypercholesterolemia, or type 2 diabetes in older, largely vitamin D-replete Australians.
Key Findings
Results
Vitamin D supplementation had no material effect on the incidence of hypertension in older Australian adults.
HR 1.00; 95% CI 0.93 to 1.08
Analysis included 10,964 participants (vitamin D, n = 5456 [49.8%]; placebo, n = 5508 [50.2%])
2672 participants (24.4%) developed hypertension over a median follow-up of 4.6 years
Incident hypertension was defined as commencing treatment with anti-hypertensive drugs, ascertained via linkage with the Australian Pharmaceutical Benefits Scheme database
Results
Vitamin D supplementation had no material effect on the incidence of hypercholesterolemia in older Australian adults.
HR 1.05; 95% CI 0.97 to 1.13
Analysis included 12,126 participants (vitamin D, n = 6038 [49.8%]; placebo, n = 6088 [50.2%])
2554 participants (21.1%) developed hypercholesterolemia over a median follow-up of 4.6 years
Incident hypercholesterolemia was defined as commencing treatment with lipid-modifying drugs
Results
Vitamin D supplementation had no material effect on the incidence of type 2 diabetes in older Australian adults.
HR 0.97; 95% CI 0.84 to 1.12
Analysis included 17,846 participants (vitamin D, n = 8931 [50.0%]; placebo, n = 8915 [50.0%])
779 participants (4.4%) developed type 2 diabetes over a median follow-up of 4.6 years
Incident T2D was defined as commencing treatment with anti-diabetic drugs
Methods
The D-Health Trial was a large randomized, double-blind, placebo-controlled trial of monthly high-dose vitamin D3 supplementation in older Australians.
Total enrollment was N = 21,315 participants aged 60-84 years
Intervention consisted of monthly doses of 60,000 international units of oral vitamin D3
Follow-up began 6 months after randomization
Outcomes were ascertained via linkage with the Australian Pharmaceutical Benefits Scheme database
Flexible parametric survival models were used to estimate the effect of vitamin D supplementation on each outcome
Background
Observational studies have found inverse associations between 25-hydroxyvitamin D concentration and risk of hypertension, hypercholesterolemia, and type 2 diabetes, but evidence from large-scale randomized controlled trials has been limited or inconclusive.
The study population was described as largely vitamin D-replete Australians
Participants were excluded if they lacked linked pharmaceutical data, were prevalent cases, or died prior to start of follow-up
The study used drug initiation as a surrogate endpoint for incident cardiometabolic conditions
Duarte Romero B, Armstrong B, Baxter C, English D, Ebeling P, Hartel G, et al.. (2026). Effect of Vitamin D Supplementation on Cardiometabolic Outcomes in Older Australian Adults-Results from the Randomized Controlled D-Health Trial.. Nutrients. https://doi.org/10.3390/nu18020357