Randomized, placebo-controlled, double-blind clinical trial on the contributions of vitamin D in the control of cardiovascular risk factors, depressive symptoms and suicide risk
American Heart Journal Plus: Cardiology Research and Practice https://doi.org/10.1016/j.ahjo.2025.100599
Brazil
| 50K weekly | Placebo | |
| Vitamin D | 58 ng | 21 ng |
| MADRS (Depression) | 7 | 22 |
| Suicide risk | 1 | 7 |
| Total Cholesterol | 193 | 239 |
| HDL | 46 | 39 |
| Triglycerides | 138 | 181 |
Objectives
To evaluate the contributions of vitamin D supplementation to the control of cardiovascular risk factors and the treatment of depressive symptoms, including suicide risk.
Methods
A randomized, placebo-controlled, double-blind clinical trial was conducted with 224 adults (18–61 years) diagnosed with major depressive disorder, recruited from psychiatric clinics of two universities in Northeast Brazil. Participants were randomized to receive vitamin D supplementation (50,000 IU/week; n = 112) or placebo (n = 112) for six months. Assessments included depressive symptoms, suicide risk, clinical/laboratory cardiovascular parameters, and serum vitamin D at baseline and day 180. Statistical analysis used chi-squared or Fisher's exact test, McNemar's test, Student's t-test or Mann-Whitney test, with odds ratios (OR) and 95 % confidence intervals (CI). Significance level was set at 5 %.
Results
Vitamin D supplementation significantly increased serum concentrations to adequate physiological levels and
led to marked reductions in
- depressive symptoms (p = 0.001) and
- suicide risk (p = 0.001).
Additionally, 13 of 15 evaluated cardiovascular risk factors showed normalization or significant reduction, without adverse events related to calcium metabolism or other side effects.
Improvements included better
- lipid profile,
- glycemic control, and
- inflammatory markers.
Clinically, these findings suggest potential for vitamin D as an adjuvant therapy in depression management, contributing to both mental health and cardiometabolic stability.
Strengths and limitations
Strengths include the rigorous double-blind, randomized design, probabilistic sampling, and comprehensive clinical-laboratory evaluation. Limitations involve the single-region sample, lack of long-term follow-up after supplementation, and the exclusion of patients with severe comorbidities, which may limit generalizability.
Conclusion
Weekly administration of 50,000 IU of vitamin D for six months proved effective in reducing depressive symptoms and suicide risk while improving cardiovascular health markers, highlighting its promise as an accessible, low-cost adjunctive therapy in psychiatric and primary care settings.
Download the PDF from VitaminDWiki
Depression Study Summary by Perplexity AI
Researchers in Brazil wanted to find out if taking vitamin D supplements could help people with depression feel better and improve their heart health. They were especially interested in whether vitamin D could reduce the risk of suicide and lower the chances of heart disease.
How The Study Worked
Who participated: 224 adults between ages 18-61 who had been diagnosed with depression by a psychiatrist
What they did: The researchers split the participants into two groups randomly:
- Treatment group: 112 people who took 50,000 IU of vitamin D once per week
- Control group: 112 people who took a fake pill (placebo) once per week
How long it lasted: 6 months
What they measured: The researchers checked depression symptoms, suicide risk, and various heart health markers before and after the treatment period.
Depression and Mental Health
- Depression symptoms got much better in people taking vitamin D compared to those taking the fake pill
- Suicide risk dropped significantly
- from 77.7% to 43.8% in the vitamin D group,
while it actually increased in the placebo group - People in the vitamin D group had fewer and less severe depressive episodes
Heart Health Improvements
The study found that 13 out of 15 heart disease risk factors improved in people taking vitamin D:
- Blood pressure: More people had normal blood pressure after taking vitamin D
- Cholesterol levels: Total cholesterol went down and "good" cholesterol (HDL) went up
- Blood sugar control: Better control of diabetes-related markers
- Heart function: The heart pumped blood better and there was less harmful thickening of heart muscle
- Inflammation: Markers of inflammation in the body decreased
Vitamin D Levels
- At the start: 82-85% of people had vitamin D deficiency
- After 6 months: 100% of people taking vitamin D supplements had adequate vitamin D levels, while 96% of the placebo group still had deficiency
Safety
The vitamin D supplements were very safe - there were no harmful side effects related to taking the supplements. The researchers carefully monitored calcium levels and other safety markers throughout the study.
Why This Matters
This study suggests that taking vitamin D supplements might be a helpful addition to regular depression treatment.
The benefits included:
- Better mood and fewer depression symptoms
- Lower risk of suicidal thoughts
- Improved heart health in multiple ways
- Safe and affordable treatment option
Important Notes
- This study was done in Brazil where there's sunshine year-round, so results might be different in places with less sun
- People in the study continued taking their regular antidepressant medications
- More research is needed to confirm these results in larger, longer studies
- Anyone considering vitamin D supplements should talk to their doctor first
Bottom Line
Taking 50,000 IU of vitamin D once per week for 6 months helped people with depression feel better mentally and improved their heart health significantly, with no serious side effects. This suggests vitamin D could be a valuable, low-cost addition to depression treatment, but more research is needed to confirm these promising results.
Related in VitaminDWiki
Weekly 50,000 IU
- Many symptoms vanquished by Vitamin D (50,000 IU weekly) - May 2025
- Depression in seniors greatly reduced by Vitamin D (50,000 IU weekly) – meta-analysis June 2023
- Breast Cancer cure rate by chemotherapy increased 2.3 X by Vitamin D (50,000 IU weekly) - RCT April 2025
- Optimal vitamin D supplementation strategies (D3 - weekly or monthly) – Feb 2017
- Multiple Sclerosis treated equally by UVB and weekly 50,000 IU of Vitamin D – RCT July 2023
- Weekly Vitamin D plus daily Magnesium is great (reduced depression in obese women in this case) – July 2021
- Stroke patients getting weekly 50,000 IU Vitamin D did better – trial March 2021
- Health problems fought by 50,000 IU weekly
50,000 IU
Depression and Suicide
- Depression substantially reduced by Vitamin D, Omega-3, Magnesium, etc – many studies
- Major Depressive Disorder RCTs often use Vitamin D: 50,000 IU weekly or single 300,000 IU - Review May 2025
- Depression: Low vitamin D in the strongest of 11 risk factors – Jan 2023
- Anti-depression medication about as good as big increase in vitamin D – meta-analysis of flawless data April 2014
- Depression reduced by 8,000 IU of Vitamin D daily – meta-analysis Nov 2024 Note: 50K weekly =7,140 IU daily
- Depression with low vitamin D increased risk of CVD and Cancer deaths – Jan 2024
- Suicide associated with low vitamin D - many studies
Cardiovascular
- Cardiovascular Disease is treated by Vitamin D - many studies 39+ meta-analyses
- Cardiovascular problems reduced by Omega-3 - many studies 34+
- Arteries and Atherosclerosis and Vitamin D - many studies 71+
- Atrial Fibrillation decreased by Vitamin D or Magnesium - many studies 26+