Improvement after a supplement is not the same as a comparative result
Start with the comparison. A before-and-after change alone cannot isolate the contribution of an ingredient.
Psyllium
Digestion and gut health
Partial research summary
Human studies reported between-group improvement in Constipation symptoms.
Single-ingredient studies · Human studies · Includes patient groups · between-group comparison
Publications for this result: 2 (1 awaiting review included)
Other outcomes and study details
Distinct publications linked to this topic: 9
- Study conditions differ; results are shown descriptively and are not pooled.
- Some publications have not cleared source or interpretation review.
- Some papers could not be reviewed, so this summary covers only findings that could be confirmed.
What has been studied?
Distinct human comparison papers: 2
Bristol stool scale score
- Comparison result:A better result than the comparison group was reported.Single ingredient
Measurement and study conditions
- Controlled human study
- Randomized trial
- Single ingredient
- Unspecified population
- Outcome role not specified
- Between-group comparison
- Timepoint: unspecified
- Study comparison: unspecified
Constipation symptoms
- Comparison result:A better result than the comparison group was reported.Patient group · Single ingredient
Measurement and study conditions
- Controlled human study
- Randomized trial
- Single ingredient
- Patient group
- Outcome role not specified
- Between-group comparison
- Timepoint: unspecified
- Study comparison: unspecified
Stool frequency
Research with unclear study subject or type
- A change was reported, but the comparison could not be confirmed.Patient group · Single ingredient
Measurement and study conditions
- Meta-analysis
- Meta-analysis
- Single ingredient
- Patient group
- Outcome role not specified
- Study subject not identified
- Timepoint: unspecified
- Study comparison: unspecified
- The study reported improvement in this measurement.Patient group
Measurement and study conditions
- Meta-analysis
- Meta-analysis
- Unknown intervention
- Patient group
- Outcome role not specified
- Between-group comparison
- Study subject not identified
- Timepoint: unspecified
- Study comparison: unspecified
symptoms
Other human research, including observational studies and reviews
- A change was reported before and after use. Its cause cannot be isolated.Patient group · Single ingredient
Measurement and study conditions
- Other evidence
- Clinical trial
- Single ingredient
- Patient group
- Primary outcome
- Within-group comparison
- Timepoint: unspecified
- Study comparison: symptom relief described after psyllium; placebo comparison is reported for microbiota but no compar
This result is held for interpretation. That does not mean research found no effect.
Outcome groups needing additional review (1)
- small bowel obstruction · Distinct papers needing additional review: 1Direction unclear: 1
One paper can appear under multiple measured outcomes or review reasons, so these counts should not be added together.
Research topics to explore
Research topics to explore
Review findings reported in each research area.
Topics with more linked papers appear first.
- View results
Blood lipids
Related papers 23 · human comparison papers 8
- LDL cholesterol · Study conditions differ · Some studies included patients or people with a deficiency
- plasma LDL-cholesterol concentration · Improvement reported
More outcome groups: 7
- View results
Glucose and metabolic health
Related papers 17 · human comparison papers 5
- Body weight · Improvement reported · Some studies used more than one ingredient · Some studies included patients or people with a deficiency
- Fasting blood sugar · Improvement reported · Some studies included patients or people with a deficiency
More outcome groups: 10
- View selected result
Digestion and gut health
Related papers 9 · human comparison papers 2
- View results
Blood pressure and vascular health
Related papers 2 · comparison findings need further review
- Systolic blood pressure · Some studies included patients or people with a deficiency · Comparison details unconfirmed
- View results
Exercise performance
Related papers 1 · comparison findings need further review
Data coverage and detailed study classifications
Paper counts are separated by research topic below. One paper may contribute to multiple findings.
Analysis status: Public-ready
Ingredient analysis date:
How the grade was determined: B
The 65.0 evidence score includes 1 independent human studies and 1 clinical studies in the representative benefit area. The B tier remains conservative because of limited repetition across independent human clinical studies, too few clinical findings with an explicit effect direction.
The grade is based mainly on the research area with the most evidence. It does not mean the same result was found in other areas.
Papers linked to this ingredient overall: 84
Papers linked to this topic 9 · distinct papers 9 · papers with a confirmed human comparison 2 · papers needing additional review 4
Ingredient-wide papers, topic-linked papers, and sources in outcome groups use different scopes. Adding source counts may count the same paper more than once.
- Bristol stool scale score: Sources represented in this measurement group: 1 · Distinct papers with human comparisons for this outcome: 1
- Constipation symptoms: Sources represented in this measurement group: 2 · Distinct papers with human comparisons for this outcome: 1
- small bowel obstruction: Sources represented in this measurement group: 1 · Distinct papers with human comparisons for this outcome: 0
- Stool frequency: Sources represented in this measurement group: 2 · Distinct papers with human comparisons for this outcome: 0
- symptoms: Sources represented in this measurement group: 1 · Distinct papers with human comparisons for this outcome: 0
Blood lipids
What the research found
serum total, LDL, and HDL cholesterol
Results for this measurement were mixed; no consistent conclusion can be drawn.
Controlled study in people · Single ingredient · Patient group
Between-group comparison
Analysis coverage and paper counts
1 paper · 1 measured outcome
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Total cholesterol
A change was reported before and after use. Its cause cannot be isolated.
Controlled study in people · Single ingredient · General population
Within-group comparison
Analysis coverage and paper counts
1 paper · 1 measured outcome
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
LDL cholesterol
The study reported improvement in this measurement.
Controlled study in people · Single ingredient · Unspecified population
Between-group comparison
Analysis coverage and paper counts
1 paper · 1 measured outcome
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
LDL-C
The study reported improvement in this measurement.
Controlled study in people · Separable contribution · Patient group
Between-group comparison
Analysis coverage and paper counts
1 paper · 1 measured outcome
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
LDL-C
The study reported improvement in this measurement.
Controlled study in people · Single ingredient · Patient group
Between-group comparison
Analysis coverage and paper counts
1 paper · 1 measured outcome
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
plasma LDL-cholesterol concentration
The study reported improvement in this measurement.
Controlled study in people · Single ingredient · Unspecified population
Between-group comparison
Analysis coverage and paper counts
1 paper · 1 measured outcome
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
ratio of total cholesterol to high-density lipoprotein cholesterol
The study reported improvement in this measurement.
Controlled study in people · Ingredient combination · Patient group
Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.
Between-group comparison
Analysis coverage and paper counts
1 paper · 1 measured outcome
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
serum total cholesterol
The study reported improvement in this measurement.
Controlled study in people · Single ingredient · Patient group
Between-group comparison
Analysis coverage and paper counts
1 paper · 1 measured outcome
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
TC levels
The study reported improvement in this measurement.
Controlled study in people · Single ingredient · Patient group
Between-group comparison
Analysis coverage and paper counts
1 paper · 1 measured outcome
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
serum total cholesterol
A change was reported before and after use. Its cause cannot be isolated.
Other evidence · Single ingredient · Patient group
Within-group comparison
Analysis coverage and paper counts
1 paper · 1 measured outcome
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
LDL cholesterol
A change was reported, but the comparison could not be confirmed.
Controlled study in people · Ingredient combination · Unspecified population
Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.
Analysis coverage and paper counts
1 paper · 1 measured outcome
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Serum cholesterol concentration
A change was reported, but the comparison could not be confirmed.
Other evidence · Single ingredient · Unspecified population
Analysis coverage and paper counts
1 paper · 1 measured outcome
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Cholesterol
The study needs further checking before its result can be interpreted.
Review · Single ingredient · Unspecified population
The comparison could not be confirmed.
Analysis coverage and paper counts
1 paper · 1 measured outcome
1 papers held from direction counts
Review overlap with primary papers is unknown; counts stay separate.
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
LDL-C
The study needs further checking before its result can be interpreted.
Controlled study in people · Separable contribution · General population
Within-group comparison
Analysis coverage and paper counts
1 paper · 1 measured outcome
1 papers held from direction counts
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Unspecified measured outcome
The study needs further checking before its result can be interpreted.
Controlled study in people · Ingredient combination · Unspecified population
Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.
The comparison could not be confirmed.
Analysis coverage and paper counts
1 paper · 1 measured outcome
1 papers held from direction counts
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Unspecified measured outcome
The study needs further checking before its result can be interpreted.
Animal study · indirect · Single ingredient · Patient group
This finding comes from animal or cell research. It does not establish the same effect in people.
The comparison could not be confirmed.
Analysis coverage and paper counts
1 paper · 1 measured outcome
1 papers held from direction counts
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Unspecified measured outcome
The study needs further checking before its result can be interpreted.
Controlled study in people · Single ingredient · Patient group
Between-group comparison
Analysis coverage and paper counts
5 papers · 5 measured outcomes
5 papers held from direction counts
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Unspecified measured outcome
The study needs further checking before its result can be interpreted.
Controlled study in people · Single ingredient · Patient group
The comparison could not be confirmed.
Analysis coverage and paper counts
1 paper · 1 measured outcome
1 papers held from direction counts
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Unspecified measured outcome
The study needs further checking before its result can be interpreted.
Meta-analysis · Single ingredient · Patient group
The comparison could not be confirmed.
Analysis coverage and paper counts
1 paper · 1 measured outcome
1 papers held from direction counts
Review overlap with primary papers is unknown; counts stay separate.
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Glucose and metabolic health
What the research found
Body weight
The study reported improvement in this measurement.
Controlled study in people · Ingredient combination · Patient group
Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.
Between-group comparison
Analysis coverage and paper counts
1 paper · 1 measured outcome
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Fasting blood sugar
The study reported improvement in this measurement.
Controlled study in people · Single ingredient · Patient group
Between-group comparison
Analysis coverage and paper counts
1 paper · 1 measured outcome
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
HbA1c
A change was reported before and after use. Its cause cannot be isolated.
Controlled study in people · Single ingredient · Patient group
Within-group comparison
Analysis coverage and paper counts
1 paper · 1 measured outcome
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
HbA1c
The study reported improvement in this measurement.
Controlled study in people · Single ingredient · Patient group
Between-group comparison
Analysis coverage and paper counts
1 paper · 1 measured outcome
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Insulin
The study reported improvement in this measurement.
Controlled study in people · Single ingredient · Patient group
Between-group comparison
Analysis coverage and paper counts
1 paper · 1 measured outcome
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
HbA1c
The study reported improvement in this measurement.
Meta-analysis · Single ingredient · General population
Between-group comparison
Analysis coverage and paper counts
1 paper · 1 measured outcome
Review overlap with primary papers is unknown; counts stay separate.
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
HOMA IR
The study reported improvement in this measurement.
Meta-analysis · Single ingredient · General population
Between-group comparison
Analysis coverage and paper counts
1 paper · 1 measured outcome
Review overlap with primary papers is unknown; counts stay separate.
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
HOMA-IR
The study reported improvement in this measurement.
Meta-analysis · Unknown intervention · Patient group
Between-group comparison
Analysis coverage and paper counts
1 paper · 1 measured outcome
Review overlap with primary papers is unknown; counts stay separate.
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Body weight
A change was reported, but the comparison could not be confirmed.
Meta-analysis · Single ingredient · Patient group
Analysis coverage and paper counts
2 papers · 2 measured outcomes
Review overlap with primary papers is unknown; counts stay separate.
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Fasting blood glucose
A change was reported, but the comparison could not be confirmed.
Other evidence · Single ingredient · Patient group
Analysis coverage and paper counts
1 paper · 1 measured outcome
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
fasting insulin level
A change was reported, but the comparison could not be confirmed.
Review · Single ingredient · Patient group
Analysis coverage and paper counts
1 paper · 1 measured outcome
Review overlap with primary papers is unknown; counts stay separate.
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
insulin and glucose responses
A change was reported, but the comparison could not be confirmed.
Review · Unknown intervention · Patient group
Analysis coverage and paper counts
1 paper · 1 measured outcome
Review overlap with primary papers is unknown; counts stay separate.
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Lower GIs
A change was reported, but the comparison could not be confirmed.
Meta-analysis · Ingredient combination · Unspecified population
Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.
Analysis coverage and paper counts
1 paper · 1 measured outcome
Review overlap with primary papers is unknown; counts stay separate.
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
plasma glucose
A change was reported, but the comparison could not be confirmed.
Controlled study in people · Single ingredient · Patient group
Analysis coverage and paper counts
1 paper · 1 measured outcome
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
plasma glucose concentration
A change was reported in animal or cell research.
Animal study · indirect · Single ingredient · Patient group
This finding comes from animal or cell research. It does not establish the same effect in people.
The comparison could not be confirmed.
Analysis coverage and paper counts
1 paper · 1 measured outcome
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Unspecified measured outcome
The study needs further checking before its result can be interpreted.
Controlled study in people · Single ingredient · Patient group
Between-group comparison
Analysis coverage and paper counts
2 papers · 2 measured outcomes
2 papers held from direction counts
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Unspecified measured outcome
The study needs further checking before its result can be interpreted.
Meta-analysis · Single ingredient · Patient group
Between-group comparison
Analysis coverage and paper counts
1 paper · 2 measured outcomes
1 papers held from direction counts
Review overlap with primary papers is unknown; counts stay separate.
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Digestion and gut health
What the research found
Bristol stool scale score
The study reported improvement in this measurement.
Controlled study in people · Single ingredient · Unspecified population
Between-group comparison
Analysis coverage and paper counts
1 paper · 1 measured outcome
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Constipation symptoms
The study reported improvement in this measurement.
Controlled study in people · Single ingredient · Patient group
Between-group comparison
Analysis coverage and paper counts
1 paper · 1 measured outcome
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
stool frequency
The study reported improvement in this measurement.
Meta-analysis · Unknown intervention · Patient group
Between-group comparison
Analysis coverage and paper counts
1 paper · 1 measured outcome
Review overlap with primary papers is unknown; counts stay separate.
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
symptoms
A change was reported before and after use. Its cause cannot be isolated.
Other evidence · Single ingredient · Patient group
Within-group comparison
Analysis coverage and paper counts
1 paper · 1 measured outcome
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Stool frequency
A change was reported, but the comparison could not be confirmed.
Meta-analysis · Single ingredient · Patient group
Analysis coverage and paper counts
1 paper · 1 measured outcome
Review overlap with primary papers is unknown; counts stay separate.
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
constipation symptoms
The study needs further checking before its result can be interpreted.
Controlled study in people · Single ingredient · Patient group
Between-group comparison
Analysis coverage and paper counts
1 paper · 1 measured outcome
1 papers held from direction counts
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
small bowel obstruction
The study needs further checking before its result can be interpreted.
Other evidence · Single ingredient · Patient group
The comparison could not be confirmed.
Analysis coverage and paper counts
1 paper · 1 measured outcome
1 papers held from direction counts
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Unspecified measured outcome
The study needs further checking before its result can be interpreted.
Controlled study in people · Single ingredient · Patient group
Between-group comparison
Analysis coverage and paper counts
1 paper · 1 measured outcome
1 papers held from direction counts
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Unspecified measured outcome
The study needs further checking before its result can be interpreted.
Cell study · indirect · Unknown intervention · Unspecified population
This finding comes from animal or cell research. It does not establish the same effect in people.
The comparison could not be confirmed.
Analysis coverage and paper counts
1 paper · 1 measured outcome
1 papers held from direction counts
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Blood pressure and vascular health
What the research found
Systolic blood pressure
A change was reported, but the comparison could not be confirmed.
Meta-analysis · Single ingredient · Unspecified population
Analysis coverage and paper counts
1 paper · 1 measured outcome
Review overlap with primary papers is unknown; counts stay separate.
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Systolic blood pressure
A change was reported, but the comparison could not be confirmed.
Review · Single ingredient · Patient group
Analysis coverage and paper counts
1 paper · 1 measured outcome
Review overlap with primary papers is unknown; counts stay separate.
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
Exercise performance
What the research found
Unspecified measured outcome
The study needs further checking before its result can be interpreted.
Other evidence · Separable contribution · Patient group
The comparison could not be confirmed.
Analysis coverage and paper counts
1 paper · 1 measured outcome
1 papers held from direction counts
Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.
How to read research findings
How should I read research findings?
Research guidesNo clear difference and an uninterpretable result are different
A reported null comparison contains a result. An abstract without an interpretable comparison leaves a question unresolved.
Paper counts and study counts are different
Count original research separately from research that reanalyzes it. Publication volume is neither replication nor a quality rating.
Side effects and combination findings
Findings from this ingredient alone are shown separately from those involving another supplement or medication.
Caution findings
2
Findings from individual and combined use, plus reviewed cautions
Key precautions
No reviewed caution rules are available yet. Reported caution findings are shown below.
These findings were reported in studies. They do not predict an individual's experience.
Findings to review with care
Side effects reported for the ingredient alone are separated from findings involving another supplement or medication.
Side effects reported with this ingredient alone
Symptoms or adverse events reported in studies without another active ingredient.
small bowel obstruction1 papers
Four patients experienced small bowel obstruction after oral psyllium seed husk use as a contrast agent.Human studies · Study type not identifiedIntestinal obstruction1 papers
Psyllium ingestion without adequate fluids caused intestinal obstruction in a 21‑year‑old man.Human studies · Observational study