Best Supplements for Reduced Depression Symptoms
Ranked by research evidence. Compare 64 supplements across 82 papers from the biomedical literature, with effect direction, evidence strength, and dose range for each.
Top picks by evidence
- Moderate evidence3 studies
Across 3 studies, all reported beneficial moderate-sized effects on reducing depression symptoms, with 2 of 3 reaching statistical significance. The evidence primarily comes from reviews and meta-analyses including multi-species probiotics or Lactobacillus plantarum, with one review specifically targeting adolescents. No specific dose or duration could be identified due to inconsistent reporting.
- Low evidence4 studies
Across 4 studies, all reported beneficial effects of Lactobacillus helveticus Rosell-52 on depression symptoms, with effect sizes ranging from small to moderate. The most robust evidence comes from a 2025 meta-analysis of 7 RCTs showing a statistically significant moderate reduction in depressive symptoms (p = 0.03; SMD, -0.55; 95% CI, -1.04 to -0.06). Probiotics appear particularly beneficial in adults, though the evidence base is small and primarily derived from reviews and a single meta-analysis.
- Low evidence3 studies
Across 3 studies, all reported beneficial moderate-sized effects of Bifidobacterium bifidum Rosell-71 (as part of probiotic blends) on reducing depressive symptoms. Two of three studies reported statistically significant findings, including a 2025 meta-analysis showing a significant reduction (p=0.03; SMD=-0.55). The most-studied dose and form were not consistently reported, and populations included adults with depression or general adult samples.
- LowLactobacillus helveticus Rosell-52Across 4 studies, all reported beneficial effects of Lactobacillus helveticus Rosell-52 on depression symptoms, with effect sizes ranging from small to moderate. The most robust evidence comes from a 2025 meta-analysis of 7 RCTs showing a statistically significant moderate reduction in depressive symptoms (p = 0.03; SMD, -0.55; 95% CI, -1.04 to -0.06). Probiotics appear particularly beneficial in adults, though the evidence base is small and primarily derived from reviews and a single meta-analysis.4 beneficial4 studies
- ModerateBifidobacterium plantarumAcross 3 studies, all reported beneficial moderate-sized effects on reducing depression symptoms, with 2 of 3 reaching statistical significance. The evidence primarily comes from reviews and meta-analyses including multi-species probiotics or Lactobacillus plantarum, with one review specifically targeting adolescents. No specific dose or duration could be identified due to inconsistent reporting.3 beneficial3 studies
- LowBifidobacterium bifidum Rosell-71Across 3 studies, all reported beneficial moderate-sized effects of Bifidobacterium bifidum Rosell-71 (as part of probiotic blends) on reducing depressive symptoms. Two of three studies reported statistically significant findings, including a 2025 meta-analysis showing a significant reduction (p=0.03; SMD=-0.55). The most-studied dose and form were not consistently reported, and populations included adults with depression or general adult samples.3 beneficial3 studies
- LowSt. John's WortAcross 3 studies, all reported beneficial effects of St. John's Wort on reducing depression symptoms, with effect sizes ranging from small to moderate. The available evidence is preliminary due to the small number of studies, and no consistent dose, duration, or population data were extracted.3 beneficial3 studies