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
Selected research topic
Glucose and metabolic health
Some measured outcomes improved in human comparison studies. Read these findings with their populations and conditions.
Findings from a combination study cannot be attributed to this ingredient alone.
Animal and cell findings do not establish the same effect in people.
Some findings concern patients or people with a deficiency.
- Publications for this topic
- 17
- Human comparison publications
- 5
- Publications needing review
- 3
Findings in the studies
Body weight
Human comparison research
- A better result than the comparison group was reported.
Several ingredients were tested together, so this ingredient’s individual effect is unknown.
What the comparison group used was not confirmed.
Patient group · Combination studyMeasurement and study conditions
- Study type
- Randomized controlled trial: subjects were randomly assigned to groups for comparison.
- Study population
- Human participants · Patient group
- Ingredients tested
- Ingredient combination
- How results were compared
- Results were compared between groups.
- Measurement time
- Not confirmed.
Research with unclear study subject or type
- A change was reported, but the comparison could not be confirmed.Single ingredient
Measurement and study conditions
- Study type
- Meta-analysis
- Study population
- Recorded population category: Patient group. Whether the research involved humans needs confirmation.
- Ingredients tested
- Single ingredient
- Measurement time
- Not confirmed.
Fasting blood sugar
- A better result than the comparison group was reported.
What the comparison group used was not confirmed.
Patient group · Single ingredientMeasurement and study conditions
- Study type
- Randomized controlled trial: subjects were randomly assigned to groups for comparison.
- Study population
- Human participants · Patient group
- Ingredients tested
- Single ingredient
- How results were compared
- Results were compared between groups.
- Measurement time
- Not confirmed.
HbA1c
Human comparison research
- A better result than the comparison group was reported.
What the comparison group used was not confirmed.
Patient group · Single ingredientMeasurement and study conditions
- Study type
- Randomized controlled trial: subjects were randomly assigned to groups for comparison.
- Study population
- Human participants · Patient group
- Ingredients tested
- Single ingredient
- How results were compared
- Results were compared between groups.
- Measurement time
- Not confirmed.
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 · 8 weeks
Measurement and study conditions
- Study type
- Randomized controlled trial: subjects were randomly assigned to groups for comparison.
- Study population
- Human participants · Patient group
- Ingredients tested
- Single ingredient
- How results were compared
- Changes within the same group were compared. · Study comparison: Intervention-group pre/post HbA1c change; abstract does not provide HbA1c between-group significance
- Additional measurement information
- Primary outcome
- Measurement time
- 8 weeks
Research with unclear study subject or type
- The study reported improvement in this measurement.Single ingredient · study durations varied
Measurement and study conditions
- Study type
- Meta-analysis
- Study population
- Recorded population category: General population. Whether the research involved humans needs confirmation.
- Ingredients tested
- Single ingredient
- How results were compared
- Results were compared between groups. · Study comparison: pooled psyllium versus placebo comparison
- Additional measurement information
- Primary outcome
- Measurement time
- study durations varied
HOMA-IR
- A better result than the comparison group was reported.Patient group · 10–12 weeks
Measurement and study conditions
- Study type
- Meta-analysis
- Study population
- Human participants · Patient group
- Ingredients tested
- Unknown intervention
- How results were compared
- Results were compared between groups. · Study comparison: Added fiber interventions vs maltodextrin or crushed-wheat controls across included trials
- Additional measurement information
- Secondary outcome
- Measurement time
- 10–12 weeks
Other measured outcomes (8)
Insulin
- A better result than the comparison group was reported.
What the comparison group used was not confirmed.
Patient group · Single ingredientMeasurement and study conditions
- Study type
- Randomized controlled trial: subjects were randomly assigned to groups for comparison.
- Study population
- Human participants · Patient group
- Ingredients tested
- Single ingredient
- How results were compared
- Results were compared between groups.
- Measurement time
- Not confirmed.
Fasting blood glucose
Other human research, including observational studies and reviews
- A change was reported, but the comparison could not be confirmed.Patient group · Single ingredient
Measurement and study conditions
- Study type
- Other evidence
- Study population
- Human participants · Patient group
- Ingredients tested
- Single ingredient
- Measurement time
- Not confirmed.
plasma glucose
Other human research, including observational studies and reviews
- A change was reported, but the comparison could not be confirmed.Patient group · Single ingredient
Measurement and study conditions
- Study type
- Randomized controlled trial: subjects were randomly assigned to groups for comparison.
- Study population
- Human participants · Patient group
- Ingredients tested
- Single ingredient
- Measurement time
- Not confirmed.
plasma glucose concentration
Animal and cell research · indirect evidence
- A change was reported in animal or cell research.Single ingredient
Measurement and study conditions
- Study type
- Animal study · indirect
- Study population
- This is animal research. The specific characteristics of the subjects need further review.
- Ingredients tested
- Single ingredient
- How results were compared
- Comparison unclear
- Measurement time
- Not confirmed.
fasting insulin level
Research with unclear study subject or type
- A change was reported, but the comparison could not be confirmed.Single ingredient
Measurement and study conditions
- Study type
- Systematic review
- Study population
- Recorded population category: Patient group. Whether the research involved humans needs confirmation.
- Ingredients tested
- Single ingredient
- Measurement time
- Not confirmed.
HOMA IR
Research with unclear study subject or type
- The study reported improvement in this measurement.Single ingredient · study durations varied
Measurement and study conditions
- Study type
- Meta-analysis
- Study population
- Recorded population category: General population. Whether the research involved humans needs confirmation.
- Ingredients tested
- Single ingredient
- How results were compared
- Results were compared between groups. · Study comparison: pooled psyllium versus placebo comparison
- Additional measurement information
- Primary outcome
- Measurement time
- study durations varied
insulin and glucose responses
Research with unclear study subject or type
- A change was reported, but the comparison could not be confirmed.postprandial
Measurement and study conditions
- Study type
- Review
- Study population
- Recorded population category: Patient group. Whether the research involved humans needs confirmation.
- Ingredients tested
- Unknown intervention
- How results were compared
- Study comparison: review summary across beta-glucan, psyllium, and guar gum; no single-ingredient comparison
- Additional measurement information
- Biomarker
- Measurement time
- postprandial
Lower GIs
Research with unclear study subject or type
- A change was reported, but the comparison could not be confirmed.
Several ingredients were tested together, so this ingredient’s individual effect is unknown.
Combination studyMeasurement and study conditions
- Study type
- Meta-analysis
- Study population
- Study subject not identified
- Ingredients tested
- Ingredient combination
- How results were compared
- Study comparison: formulations containing psyllium and other listed ingredients
- Additional measurement information
- Secondary outcome
- Measurement time
- Not confirmed.
Representative outcome and study details
Human studies reported between-group improvement in Body weight; while Studies with an unspecified organism reported a change with no confirmed comparison group in Body weight.
These conditions come from related studies and may not describe a single paper.
single- and combination-ingredient studies · Individual ingredient effects cannot be separated · Human studies · Includes patient groups · between-group comparison · comparator not confirmed
3 publications linked to this result
- Study conditions differ; results are shown descriptively and are not pooled.
- Combination, formula, or class studies do not isolate this ingredient or establish synergy.
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 17 · distinct papers 17 · papers with a confirmed human comparison 5 · papers needing additional review 3
A publication may appear in more than one count. These numbers should not be added. 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.
- Body weight: Sources represented in this measurement group: 3 · Distinct papers with human comparisons for this outcome: 1
- Fasting blood glucose: Sources represented in this measurement group: 1 · Distinct papers with human comparisons for this outcome: 0
- Fasting blood sugar: Sources represented in this measurement group: 1 · Distinct papers with human comparisons for this outcome: 1
- fasting insulin level: Sources represented in this measurement group: 1 · Distinct papers with human comparisons for this outcome: 0
- HbA1c: Sources represented in this measurement group: 3 · Distinct papers with human comparisons for this outcome: 1
- HOMA IR: Sources represented in this measurement group: 1 · Distinct papers with human comparisons for this outcome: 0
- HOMA-IR: Sources represented in this measurement group: 1 · Distinct papers with human comparisons for this outcome: 1
- Insulin: Sources represented in this measurement group: 1 · Distinct papers with human comparisons for this outcome: 1
- insulin and glucose responses: Sources represented in this measurement group: 1 · Distinct papers with human comparisons for this outcome: 0
- Lower GIs: Sources represented in this measurement group: 1 · Distinct papers with human comparisons for this outcome: 0
- plasma glucose: Sources represented in this measurement group: 1 · Distinct papers with human comparisons for this outcome: 0
- plasma glucose concentration: Sources represented in this measurement group: 1 · Distinct papers with human comparisons for this outcome: 0
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.
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.
No reviewed caution rules are available yet. Reported caution findings are shown below.
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