Is a daily supplementation with 40 microgram vitamin D3 sufficient? A randomised controlled trial.
Study Goal
The researchers aimed to evaluate the effect of daily vitamin D₃ and calcium supplementation on serum 25-hydroxyvitamin D levels and markers of bone and mineral metabolism.
Results Summary
Supplementation with 40 μg vitamin D₃ and 1,000 mg calcium daily significantly increased serum 25(OH)D levels without adverse effects, while calcium alone did not affect these levels. Bone metabolism markers (BALP and TRACP5b) remained unchanged in both groups.
Population
45 community-dwelling adults (32 females), aged 55-84 years, living at 58° North latitude.
Effective Dosage
1,000 mg calcium per day.
Duration
1 year.
Interactions
None mentioned.
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
40 μg (1,600 IU) per day of vitamin D(3) | neutral | serum 25-hydroxyvitamin D (25(OH)D) and markers of bone and mineral metabolism | community-dwelling subjects (32 females), age 55-84 years, at 58° North latitude | - | was evaluated | #1 |
40 μg vitamin D(3) plus 1,000 mg calcium per day | neutral | - | community-dwelling subjects (32 females), age 55-84 years, at 58° North latitude | 1 year | supplemented | #2 |
40 μg vitamin D(3) plus 1,000 mg calcium per day | increase | 25(OH)D level | subjects supplemented with vitamin D(3) | above 50 nmol/L | reached a 25(OH)D level above 50 nmol/L | #3 |
40 μg vitamin D(3) plus 1,000 mg calcium per day | increase | Mean (SD) serum 25(OH)D | vitamin D(3) supplemented group | from 50.4 (13.5) nmol/L to 84.2 (17.5) nmol/L | increased from 50.4 (13.5) nmol/L to 84.2 (17.5) nmol/L | #4 |
1,000 mg calcium per day | no change | serum 25(OH)D | control group | 47.3 (14.1) nmol/L and 45.7 (13.4) nmol/L | corresponding levels were 47.3 (14.1) nmol/L and 45.7 (13.4) nmol/L | #5 |
40 μg vitamin D(3) plus 1,000 mg calcium per day | no change | serious adverse event | study group | - | No serious adverse event was recorded | #6 |
40 μg vitamin D(3) plus 1,000 mg calcium per day | no change | BALP and TRACP5b | - | - | did not change significantly | #7 |
daily supplementation with 40 μg vitamin D(3) | increase | 25(OH)D level | - | 50 nmol/L | is sufficient to secure a 25(OH)D level of 50 nmol/L | #8 |
daily supplementation with 40 μg vitamin D(3) | no change | side effects | study group | - | No side effects were observed | #9 |
PURPOSE: The effect of 40 μg (1,600 IU) per day of vitamin D(3) on serum 25-hydroxyvitamin D (25(OH)D) and markers of bone and mineral metabolism was evaluated. METHODS: This intervention study was designed as a double-blind randomised controlled trial. Forty-five community-dwelling subjects (32 females), age 55-84 years, at 58° North latitude were supplemented for 1 year with 40 μg vitamin D(3) plus 1,000 mg calcium per day, or with 1,000 mg calcium per day for controls. Safety parameters and 25(OH)D, intact parathyroid hormone (PTH), ionized calcium, bone-specific alkaline phosphatase (BALP), and tartrate-resistant acid phosphatase isoform 5b (TRACP5b) were measured over the study period. RESULTS: All subjects supplemented with vitamin D(3) reached a 25(OH)D level above 50 nmol/L. Mean (SD) serum 25(OH)D increased from 50.4 (13.5) nmol/L to 84.2 (17.5) nmol/L, range 55.0-125.0 nmol/L in the vitamin D(3) supplemented group and the corresponding levels for the control group were 47.3 (14.1) nmol/L and 45.7 (13.4) nmol/L, range 26.0-73.0 nmol/L. No serious adverse event was recorded and the highest 25(OH)D level reached, 125.0 nmol/L, is well below toxic levels. BALP and TRACP5b did not change significantly over the study period. CONCLUSIONS: This trial suggests that a daily supplementation with 40 μg vitamin D(3) is sufficient to secure a 25(OH)D level of 50 nmol/L. No side effects were observed in the study group.