According to Gram Research analysis, vitamin D supplementation reduced anxiety symptoms in young people with depression and low vitamin D levels, with a statistically significant reduction of 1.78 points on anxiety scales compared to placebo (p=0.026). Young adults aged 18-24 with moderate-to-severe depression showed improvements in both depression and anxiety, though overall depression symptoms didn’t significantly improve across the entire group of 108 participants who took 4,800 IU daily for 8 weeks.
Researchers tested whether vitamin D supplements could help young people aged 10-24 who had depression and low vitamin D levels. In this study of 108 participants, those who took 4,800 IU of vitamin D daily for 8 weeks showed reduced anxiety compared to those taking a placebo. Interestingly, the vitamin D didn’t significantly reduce depression overall, but it did help young adults with moderate-to-severe depression feel less anxious. The results suggest vitamin D might be a helpful addition to depression treatment, especially for anxiety, though researchers say more studies are needed to confirm these findings.
Key Statistics
A 2026 randomized controlled trial of 108 young people found that vitamin D supplementation reduced anxiety by 1.78 points compared to placebo (p=0.026) in those with depression and vitamin D deficiency.
Among 108 participants aged 10-24 with depression and low vitamin D, young adults with moderate-to-severe depression showed significant improvements in both depression and anxiety after 8 weeks of 4,800 IU daily vitamin D supplementation.
In a 2026 study of 108 young people, vitamin D supplementation did not significantly reduce overall depression symptoms compared to placebo, but anxiety improvements were statistically significant (p=0.026).
The Quick Take
- What they studied: Whether taking vitamin D supplements could reduce depression and anxiety symptoms in young people who had low vitamin D levels and depression.
- Who participated: 108 young people aged 10-24 years old who had major depression and vitamin D insufficiency or deficiency. About half had mild-to-moderate depression, and half had moderate-to-severe depression.
- Key finding: Vitamin D supplementation reduced anxiety symptoms by about 1.78 points on the anxiety scale compared to placebo (p=0.026). For young adults with moderate-to-severe depression, vitamin D also reduced both depression and anxiety, though the overall group showed no significant depression improvement.
- What it means for you: If you’re a young person with depression and low vitamin D, taking vitamin D supplements might help reduce anxiety feelings. However, this is early research, and vitamin D shouldn’t replace other depression treatments like therapy or medication. Talk to your doctor before starting supplements.
The Research Details
This was a partially randomized controlled trial, which means some participants chose to take vitamin D while others were randomly assigned to either vitamin D or placebo (fake pill). The study lasted 8 weeks, with participants taking 4,800 IU of vitamin D3 daily. Researchers measured depression using two different scales: one where a doctor assessed symptoms, and one where participants rated their own symptoms. They also measured anxiety using a standard questionnaire.
The study included 108 young people split into three groups: 41 received vitamin D through randomization, 28 chose to take vitamin D, and 39 received placebo. This design allowed researchers to see if vitamin D worked better than placebo while also respecting participants’ preferences.
The researchers used computer-generated random assignments and kept everyone (participants, doctors, and researchers) blinded to who received vitamin D or placebo, which reduces bias in the results.
Using a randomized design with blinding is important because it helps prove that any improvements come from the vitamin D itself, not from expectations or other factors. By measuring depression and anxiety in multiple ways, researchers could see if vitamin D helped with specific symptoms. The 8-week timeframe is long enough to see real changes in mood.
This study has several strengths: it used randomization, blinding, and multiple measurement methods. However, the sample size of 108 is relatively small, which means the results are exploratory rather than definitive. The researchers themselves noted that larger studies are needed. The study was completed as planned with no safety concerns reported.
What the Results Show
The main finding was that vitamin D supplementation did not significantly reduce overall depression symptoms compared to placebo in the full study group. However, when researchers looked at anxiety specifically, they found that the vitamin D group had significantly lower anxiety scores than the placebo group (a reduction of 1.78 points, p=0.026).
When researchers examined subgroups, they discovered something important: young adults (ages 18-24) with moderate-to-severe depression who took vitamin D showed improvements in both depression and anxiety compared to placebo. This suggests vitamin D might be especially helpful for people with more serious depression.
Interestingly, adolescents (ages 10-19) with moderate-to-severe depression did not show the same benefits from vitamin D compared to placebo. This age difference suggests that vitamin D’s effects might work differently in younger teens versus older teens and young adults.
There were no safety concerns. Researchers checked for signs of too much calcium in the blood (hypercalcemia) and found no problems in either group.
Self-reported depression scores (measured by the Beck Depression Inventory) and anxiety scores (measured by the Generalized Anxiety Disorder scale) both showed improvements in the vitamin D group, though the depression improvement wasn’t statistically significant. The preference group (people who chose vitamin D) showed similar results to the randomized vitamin D group, suggesting that choice didn’t affect the outcome.
Previous research has suggested a link between low vitamin D and depression, but studies on whether vitamin D supplements actually help have shown mixed results. This study adds to that evidence by showing that vitamin D may help with anxiety and possibly with depression in people with moderate-to-severe symptoms. The finding that vitamin D works differently in young adults versus adolescents is new and suggests age matters when considering vitamin D treatment.
The biggest limitation is the small sample size of 108 participants, which means the results are exploratory and shouldn’t be considered final proof. The study only lasted 8 weeks, so we don’t know if benefits continue longer. The study didn’t measure vitamin D blood levels after supplementation, so we can’t confirm everyone’s vitamin D actually increased. The age range (10-24) is quite broad, and the study shows effects differ by age, suggesting future research should focus on specific age groups. Finally, this study only included people with depression and low vitamin D, so results may not apply to everyone.
The Bottom Line
If you’re a young person (especially ages 18-24) with depression and low vitamin D levels, vitamin D supplementation may help reduce anxiety symptoms. The evidence is moderate strength—promising but not yet definitive. Vitamin D should be considered as part of a complete treatment plan that may include therapy, medication, and lifestyle changes. Always consult with your doctor before starting any supplement, especially if you’re taking other medications. The dose used in this study was 4,800 IU daily, but your doctor may recommend a different amount based on your individual needs.
Young people aged 10-24 with depression and confirmed low vitamin D levels should pay attention to this research. It may be especially relevant for those with moderate-to-severe depression. People with mild-to-moderate depression may see less benefit. This research is less clear for adolescents under 18, so younger teens should discuss vitamin D supplementation carefully with their doctor. Anyone with kidney disease, heart disease, or conditions affecting calcium metabolism should consult their doctor before supplementing.
In this study, anxiety improvements appeared within 8 weeks of starting vitamin D supplementation. However, individual results vary. Some people might notice changes sooner, while others might need the full 8 weeks. Depression improvements, when they occurred, also appeared within this timeframe. It’s important to continue other depression treatments while trying vitamin D, as it’s not a replacement for therapy or medication.
Frequently Asked Questions
Does vitamin D help with depression in teenagers?
Vitamin D may help reduce anxiety in young people with depression and low vitamin D levels. A 2026 study of 108 participants found anxiety reduced by 1.78 points with vitamin D versus placebo. However, effects appear stronger in young adults (18-24) than younger adolescents, and vitamin D shouldn’t replace other depression treatments.
How much vitamin D should I take for depression?
The study used 4,800 IU of vitamin D3 daily for 8 weeks. However, the right dose for you depends on your age, current vitamin D levels, and overall health. Talk to your doctor before starting supplements—they can test your vitamin D level and recommend the appropriate dose for your situation.
Can vitamin D replace antidepressants or therapy?
No. Vitamin D supplementation should be considered as part of a complete depression treatment plan, not a replacement for therapy, medication, or other treatments. This research suggests vitamin D may help reduce anxiety alongside other treatments, but it’s not a standalone cure for depression.
How long does it take for vitamin D to help with anxiety?
In this 8-week study, anxiety improvements appeared within that timeframe. Individual results vary—some people might notice changes sooner, others might need the full 8 weeks. Continue taking vitamin D consistently and track your symptoms to see if it’s helping you personally.
Is vitamin D supplementation safe for young people?
The 2026 study found no safety concerns with 4,800 IU daily for 8 weeks, with no cases of dangerously high calcium levels. However, safety depends on individual health conditions. Always consult your doctor before starting supplements, especially if you have kidney disease, heart problems, or take other medications.
Want to Apply This Research?
- Track anxiety levels daily using a simple 1-10 scale, and record vitamin D supplementation doses. Note any changes in sleep, mood, or energy levels weekly. Compare anxiety scores from week 1 to week 8 to see if vitamin D is helping.
- Set a daily reminder to take your vitamin D supplement at the same time each day (ideally with a meal containing fat for better absorption). Log your anxiety symptoms each evening using the app’s mood tracker. Share weekly summaries with your doctor to monitor progress.
- Use the app to create a baseline anxiety score before starting vitamin D. Track anxiety weekly for 8 weeks to match the study timeline. Create a chart showing your anxiety trend over time. If you see improvement, continue supplementation and discuss with your doctor. If no improvement after 8 weeks, discuss alternative approaches with your healthcare provider.
This research is exploratory and should not be considered definitive medical advice. Vitamin D supplementation is not a replacement for professional mental health treatment, including therapy and medication. If you or someone you know is struggling with depression or anxiety, please consult with a qualified healthcare provider, therapist, or psychiatrist. Always speak with your doctor before starting any new supplement, especially if you have existing health conditions or take medications. The findings apply specifically to young people aged 10-24 with depression and vitamin D insufficiency/deficiency; results may not apply to everyone. In case of mental health crisis, contact a crisis helpline or emergency services immediately.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.