Dr. Grey AI

Depression

Depression is a chronic state of low mood often associated with hopelessness, apathy, and fatigue. Unlike sadness, depression is a disorder that persists for weeks or months and interferes with daily life.

Quick Answer

What it is

Depression is a chronic state of low mood often associated with hopelessness, apathy, and fatigue. Unlike sadness, depression is a disorder that persists for weeks or months and interferes with daily life.

Key findings

  • Grade A: Depression Symptoms (St. John's Wort)
  • Grade A: Anxiety Symptoms (Curcumin)
  • Grade B: Combined Anxiety & Depression (Vitamin D)

Safety

No specific caution or interaction language was detected in the current summary/outcome notes.

ℹ️ Quick Facts

Quick Facts: Depression

  • Supplements Studied:30
  • Research Trials:67
  • Total Participants:81,835
  • Grade A Supplements:3
  • Top Supplement:Fish Oil (A)
67 trials
81,835 ppts
30 supps · 98 outcomes

Evidence-Based Protocol

Supplement stack ranked by research quality

Strong Evidence

Primary Stack (Tier 1)

Omega-3 Fatty Acids (EPA)A
1-2g EPA daily (EPA-dominant formula, EPA:DHA ratio >2:1)

EPA reduces neuroinflammation, modulates HPA axis, and enhances serotonin receptor sensitivity and neurotransmission

30 studies | 2,000 participants
St. John's WortA
300mg 3x daily (standardized to 0.3% hypericin)

Inhibits reuptake of serotonin, dopamine, and norepinephrine; modulates GABA receptors

35 studies | 6,000 participants

Supporting Stack (Tier 2)

SAMe (S-Adenosyl-L-Methionine)A
400-1600mg daily (start low, titrate up)

Methyl donor supporting neurotransmitter synthesis and phospholipid methylation in neuronal membranes

22 studies | 1,500 participants
Vitamin DB
2000-5000 IU daily (target 40-60 ng/mL)

Vitamin D receptors in brain regulate serotonin synthesis; deficiency strongly linked to depression

25 studies | 2,000 participants
Saffron ExtractA
30mg daily (standardized extract)

Crocin and safranal modulate serotonin and dopamine reuptake inhibition with anxiolytic effects

15 studies | 800 participants
CurcuminA
500-1000mg daily (enhanced bioavailability form)

Anti-inflammatory effects reduce neuroinflammation; enhances BDNF and modulates monoamine neurotransmitters

12 studies | 700 participants

How It Works

Depression involves complex changes in brain chemistry, inflammation, and neuroplasticity. While severe depression requires professional treatment, several supplements have strong evidence for improving symptoms, either alone for mild-moderate depression or alongside conventional treatment.

•Omega-3 Fatty Acids (EPA) have robust evidence for depression. The brain is highly enriched in omega-3s, and deficiency is linked to depression. EPA specifically reduces neuroinflammation (increasingly recognized as a factor in depression) and enhances serotonin signaling. Studies show significant benefit, especially with EPA-dominant formulas. The effect is strongest in people already on antidepressants (augmentation).
•St. John's Wort is one of the most studied natural antidepressants. It works similarly to prescription antidepressants by preventing the reuptake of serotonin, dopamine, and norepinephrine. Cochrane reviews show it's as effective as SSRIs for mild-moderate depression with fewer side effects. CRITICAL: Do not combine with prescription antidepressants or many other medications—it has major drug interactions.
•SAMe is a natural compound involved in neurotransmitter synthesis. It's been used in Europe for decades as a prescription antidepressant. SAMe supports the production of serotonin, dopamine, and norepinephrine. It works relatively quickly, often within 1-2 weeks. Also beneficial if taking medications that deplete SAMe.
•Vitamin D deficiency is very common in people with depression, and there's evidence the relationship is causal. Vitamin D receptors in the brain regulate genes involved in serotonin synthesis. Supplementation can improve mood, especially in those who are deficient.
•Saffron has surprisingly strong evidence—multiple studies show it's as effective as fluoxetine (Prozac) for mild-moderate depression. It works on serotonin and dopamine systems. It's expensive but effective.
•Curcumin addresses the inflammatory component of depression. Chronic inflammation is increasingly recognized as a driver of depression in many people. Curcumin also increases BDNF (brain-derived neurotrophic factor), which supports neuroplasticity.

Expected timeline: SAMe may show effects within 1-2 weeks. Saffron and curcumin effects typically appear within 4-6 weeks. Omega-3s require 8+ weeks for full benefit. St. John's Wort takes 4-6 weeks.

Generated from peer-reviewed researchSchema v2.0

Supplements for Depression

Sorted by strength of evidence

AFish Oil
1
↓Depression SymptomsImproves↓Postpartum Depression SymptomsImproves
ASt. John's Wort
1
↓Depression SymptomsImproves
ACurcumin
1
↓Anxiety SymptomsImproves↓Depression SymptomsImproves↓CortisolImproves
BS-adenosylmethionine
2
↓Depression SymptomsImprovesAttention↑ItchingImproves
BSaffron
1
↓Anxiety SymptomsImprovesAppetite↓Depression SymptomsImproves
BCoenzyme Q10
1
↓Depression SymptomsImproves↓Fatigue SymptomsImproves
BVitamin D
1
↓Combined Anxiety & DepressionImproves↓Depression SymptomsImproves
B5-HTP
1
↓Depression SymptomsImproves
BMelatonin
1
↓Depression SymptomsImproves↑Serum BDNFImproves
BFolic Acid (Vitamin B9)
1
↓Depression SymptomsImproves↓Schizophrenia symptomsImproves
BRhodiola Rosea
1
↓Depression SymptomsImproves↓Insomnia Signs and SymptomsImproves↑Subjective Well-BeingImproves
CZinc
1
↑AggressionImproves↓Depression SymptomsImproves↑Serum BDNFImproves
CProbiotics
1
↓Depression SymptomsImproves↑Sleep QualityImproves↑Sleep DurationImproves
CChromium
1
↓AppetiteImproves↓Depression SymptomsImproves↑LibidoImproves
CApigenin
1
↓Depression SymptomsImproves
CRed Clover Extract
1
↓Anxiety SymptomsImproves↓Depression SymptomsImproves
CNefiracetam
1
↓ApathyImprovesDepression Symptoms
CGABA
1
↓Depression SymptomsImproves
CTheanine
1
↓Anxiety SymptomsImproves↑AttentionImproves↓Depression SymptomsImproves
CMagnesium
1
↓C-Reactive Protein (CRP)Improves↓Depression SymptomsImproves↑Serum BDNFImproves

Detailed Outcomes

Grade:
Effect:
Size:
Sort:
|
A
Depression Symptoms
Moderate Improvement
18 studies
moderate↓Improves
A
Anxiety Symptoms
Large Improvement
5 studies
large↓Improves
?
Depression Symptoms
9 studies
↓Improves
?
Cortisol
1 study
↓Improves
?
Interleukin 1-beta
1 study
↓Improves
?
Serum BDNF
1 study
↑Improves
?
TNF-Alpha
1 study
↓Improves
A
Depression Symptoms
Moderate Improvement
4 studies
moderate↓Improves
?
Postpartum Depression Symptoms
2 studies
↓Improves
B
Combined Anxiety & Depression
Small Improvement
25 studies
small↓Improves
?
Depression Symptoms
10 studies
↓Improves
B
Depression Symptoms
Small Improvement
17 studies
small↓Improves
?
Serum BDNF
5 studies
↑Improves
B
Depression Symptoms
Small Improvement
11 studies
small↓Improves
D
Attention
No effect
1 study
none
?
Itching
5 studies
↑Improves
?
Osteoarthritis Symptoms
3 studies
↓Improves
?
Memory
1 study
↑Improves
?
Motivation
1 study
↑Improves
B
Depression Symptoms
Moderate improvement in depression symptoms
7 studies
moderate↓Improves
B
Anxiety Symptoms
Small Improvement
4 studies
small↓Improves
D
Appetite
No effect
1 study
none
?
Depression Symptoms
8 studies
↓Improves
?
Sleep Quality
2 studies
↑Improves
?
Homocysteine
1 study
↓Improves
?
Hot Flash Symptoms
1 study
↓Improves
?
Sexual Function
1 study
↑Improves
?
Subjective Well-Being
1 study
↑Improves
?
Weight
1 study
↓Improves
B
Depression Symptoms
Small Improvement
3 studies
small↓Improves
?
Schizophrenia symptoms
1 study
↓Improves
B
Depression Symptoms
Small Improvement
3 studies
small↓Improves
?
Insomnia Signs and Symptoms
1 study
↓Improves
?
Subjective Well-Being
1 study
↑Improves
B
Depression Symptoms
Moderate Improvement
2 studies
moderate↓Improves
?
Fatigue Symptoms
1 study
↓Improves
C
Depression Symptoms
Small Improvement
25 studies
small↓Improves
C
Anxiety Symptoms
Small Improvement
23 studies
small↓Improves
?
Quality of Life
9 studies
↑Improves
C
Depression Symptoms (Mild-Moderate)
Better than placebo for mild-moderate depression (Cochrane review)
10 studies
moderate↓Improves
D
Severe Depression
Not effective for severe depressive symptoms
5 studies
small↓Improves
C
Depression Symptoms
Small Improvement
2 studies
small↓Improves
?
Sleep Quality
6 studies
↑Improves
?
Sleep Duration
3 studies
↑Improves
?
Sleep Latency
3 studies
↓Improves
?
Sleep Efficiency
2 studies
↑Improves
C
Aggression
Small Improvement
1 study
small↑Improves
?
Depression Symptoms
4 studies
↓Improves
?
Serum BDNF
2 studies
↑Improves
?
Interleukin 6
1 study
↓Improves
?
Subjective Well-Being
1 study
↑Improves
?
TNF-Alpha
1 study
↓Improves
C
Appetite
Small Decrease
1 study
small↓Improves
?
Depression Symptoms
2 studies
↓Improves
?
Libido
1 study
↑Improves
C
Depression Symptoms
Moderate Decrease in Hamilton Depression Rating Scale
1 study
moderate↓Improves
C
Anxiety Symptoms
Moderate Improvement
1 study
moderate↓Improves
?
Depression Symptoms
1 study
↓Improves
C
Apathy
Small Improvement
1 study
small↓Improves
D
Depression Symptoms
No effect
1 study
none
C
Depression Symptoms
Improvement in depression scores (90-day trial with exercise)
1 study
moderate↓Improves
C
Anxiety Symptoms
Small Improvement
1 study
small↓Improves
?
Attention
1 study
↑Improves
?
Depression Symptoms
1 study
↓Improves
?
Executive Function
1 study
↑Improves
?
Motor Speed
1 study
↑Improves
?
Sleep Quality
1 study
↑Improves
?
Verbal Fluency
1 study
↑Improves
?
Verbal Memory
1 study
↑Improves
?
Working Memory
1 study
↑Improves
C
C-Reactive Protein (CRP)
Small Decrease
1 study
small↓Improves
?
Depression Symptoms
3 studies
↓Improves
?
Serum BDNF
2 studies
↑Improves
?
Serum Magnesium
2 studies
↑Improves
?
Interleukin 6
1 study
↓Improves
?
TNF-Alpha
1 study
↓Improves
D
Depressive Symptoms
Meta-analysis: SMD 0.15 (-0.01-0.32, p=0.07) - trend but not significant
12 studies
none
D
Cognition
No effect
9 studies
none
D
Depression Symptoms
No effect
5 studies
none
?
Fatigue Symptoms
1 study
↓Improves
D
Anxiety Symptoms
No effect
2 studies
none
?
Depression Symptoms
5 studies
↓Improves
D
Anxiety Symptoms
No effect
1 study
none
D
Depression Symptoms
No effect
1 study
none
?
Sleep Quality
1 study
↑Improves
?
Subjective Well-Being
1 study
↑Improves
D
Libido
No effect
1 study
none
?
Sleep Quality
1 study
↑Improves
D
Bipolar Disorder Symptoms
No effect
1 study
none
?
Depression Symptoms
4 studies
↓Improves
?
Schizophrenia symptoms
1 study
↓Improves
D
Depression Symptoms
No effect
1 study
none
D
Postpartum Depression Symptoms
No effect
1 study
none
?
Depression Symptoms
9 studies
↓Improves
?
Depression Symptoms
3 studies
↓Improves
?
Depression Symptoms
2 studies
↓Improves
?
Depression Symptoms
1 study
↓Improves
?
Sexual Function
1 study
↑Improves

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