Supplement
Synbiotics pair live beneficial bacteria with prebiotic fibers that feed them, aiming to support the community of microbes in your gut. The best-supported research looked at blood pressure in people with fatty liver disease, where the evidence is moderate but results were mixed across 319 participants. Elsewhere, studies found no clear difference in abdominal pain in irritable bowel syndrome, body fat in fatty liver disease, or height in malnutrition, and that evidence is very limited.
- Updated
- How we grade
- 7 studies cited
- Best evidence
- Grade B
- Conditions studied
- 5
- Outcomes
- 33
- Graded outcomes
- 0203
Evidence by condition
- Strong
- Moderate
- Limited
- Very limited
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Blood Pressure Mixed effect | 319 people | |||||
| Body Fat No effect | NoneNo effect | 227 people | ||||
| Liver Enzymes | Changes; see studies | 1 study | 957 people | |||
| Weight | Improves (the measure goes down) | 1 study | 701 people | |||
| Body Mass Index (BMI) | Improves (the measure goes down) | 1,921 people | ||||
| C-Reactive Protein (CRP) | Improves (the measure goes down) | 478 people | ||||
| High-density lipoprotein (HDL) | Improves (the measure goes up) | 1 person | ||||
| Insulin Resistance | Improves (the measure goes down) | 1,921 people | ||||
| Liver Fat | Improves (the measure goes down) | 137 people | ||||
| Liver Fibrosis | Improves (the measure goes down) | 238 people | ||||
| Low-density lipoprotein (LDL) | Improves (the measure goes down) | 1 person | ||||
| TNF-Alpha | Improves (the measure goes down) | 233 people | ||||
| Total cholesterol | Improves (the measure goes down) | 877 people | ||||
| Triglycerides | Improves (the measure goes down) | 1 person | ||||
| Waist circumference | Improves (the measure goes down) | 316 people | ||||
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Blood Pressure Mixed effect | 319 people | |||||
| Liver Enzymes | Changes; see studies | 1 study | 957 people | |||
| Weight | Improves (the measure goes down) | 1 study | 701 people | |||
| Body Fat | Improves (the measure goes down) | 227 people | ||||
| C-Reactive Protein (CRP) | Improves (the measure goes down) | 478 people | ||||
| Liver Fat | Improves (the measure goes down) | 137 people | ||||
| Liver Fibrosis | Improves (the measure goes down) | 238 people | ||||
| TNF-Alpha | Improves (the measure goes down) | 233 people | ||||
| Total cholesterol | Improves (the measure goes down) | 877 people | ||||
| Waist circumference | Improves (the measure goes down) | 316 people | ||||
Irritable Bowel Syndrome (IBS)
- Abdominal Pain
- Bloating: improves
- Irritable Bowel Syndrome Symptoms: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Abdominal Pain No effect | NoneNo effect | 8,315 people | ||||
| Bloating | Improves (the measure goes down) | 8,315 people | ||||
| Irritable Bowel Syndrome Symptoms | Improves (the measure goes down) | 8,315 people | ||||
| Quality of Life | Improves (the measure goes up) | 8,315 people |
Malnutrition
- Height
- Weight: changes; see studies
- Lower Respiratory Tract Infection Risk: changes; see studies
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Height No effect | NoneNo effect | 706 people | ||||
| Weight | Changes; see studies | 1 study | 708 people | |||
| Lower Respiratory Tract Infection Risk | Changes; see studies | 3,086 people | ||||
Cystic Fibrosis
- Lung Function: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Lung Function | Improves (the measure goes up) | 81 people |
Key findings
- Blood Pressure
- Body Fat
- Abdominal Pain
Shop the evidence-backed picks
Third-party tested Synbiotics products, in the forms the graded studies used where we can match them.
- Grade B
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Studies cited
7 studies from PubMed
- The efficacy of probiotics, prebiotics, and synbiotics on anxiety, depression, and sleep: a systematic review and meta-analysis of randomized controlled trials.
- The Efficacy of Probiotics, Prebiotics, Synbiotics, and Fecal Microbiota Transplantation in Irritable Bowel Syndrome: A Systematic Review and Network Meta-Analysis.
- The effect of gut microbiome-targeted therapies in nonalcoholic fatty liver disease: a systematic review and network meta-analysis.
- The effect of probiotic, prebiotic, and synbiotic supplements on anthropometric measures and respiratory infections in malnourished children: a systematic review and meta-analysis of randomized controlled trials.
- Effectiveness of Probiotics, Prebiotics, and Symbiotic Supplementation in Cystic Fibrosis Patients: A Systematic Review and Meta-Analysis of Clinical Trials.
- The effect of synbiotics on liver enzymes, obesity indices, blood pressure, lipid profile, and inflammation in patients with non-alcoholic fatty liver: A systematic review and meta-analysis of randomized controlled trials.
- Effect of synbiotics on the cardiovascular risk factors in patients with non-alcoholic fatty liver: a GRADE assessed systematic review and meta-analysis.