Guar gum, fenugreek and metabolic health in 50 trials
What it found
In 50 randomised trials in adults, guar gum was linked to more consistent improvements in cholesterol and other blood fats, while fenugreek was linked to more consistent improvements in blood sugar.
Body weight and BMI changes were less consistent.
What they found
Studies in people
Blood sugar
Fenugreek preparations consistently improved blood sugar measures. The largest drop in fasting blood glucose was from 157.33 mg/dL to 108.2 mg/dL with 20 g/day fenugreek seed powder for 2 months in people with type 2 diabetes.
Blood fats
Guar gum had more consistent effects on cholesterol and other blood fats. The largest improvements in blood fats were seen with 50 g/day fenugreek for 30 days in people with type 2 diabetes, where total cholesterol fell by 29.81 mg/dL, triglycerides fell by 60.24 mg/dL, and HDL cholesterol rose by 10.5 mg/dL.
Body weight and BMI
Effects on body weight and BMI were less consistent. The largest weight drop was 5.6% with 500 mg/day fenugreek seed extract, and the largest BMI drop was 6.5% with 3.5 g/day guar gum, but most studies found only small changes.
Side effects
No major harmful side effects of any fibre type were reported in any of the included studies.
Dose and duration
Doses varied widely, from 50 mg to 100 g per day, and study lengths ranged from 2 hours to 12 months, though most lasted 6 to 8 weeks. No clear dose-response relationship was seen for fasting blood glucose.
Other findings
Study quality
Most studies had some concerns or high risk of bias, mainly due to lack of blinding, co-interventions and incomplete follow-up. Outcome measurement was low risk in almost all studies because biochemical markers were used.
What the authors conclude
“Our findings suggest that the metabolic effects of galactomannans are source-dependent, with fenugreek-based interventions appearing to have greater potential for improving glycemic outcomes, while guar gum may be more effective in improving lipid parameters.”
Also in their conclusions
- They conclude that the metabolic effects of galactomannans depend on the source, with fenugreek appearing to have greater potential for improving blood sugar outcomes and guar gum possibly more effective for blood fats.
- They say that since these fibres can be easily consumed as dietary supplements, it is worth considering their regular, daily intake.
- They call for additional randomised controlled trials to test fenugreek seed supplementation in women with polyendocrine metabolic ovarian syndrome.
How it was done
The authors wanted to compare how different galactomannan fibres affect blood sugar, blood fats and body weight, because the evidence was mixed and it was unclear whether the source of the fibre matters.
They searched three databases for randomised controlled trials in adults that tested guar gum, locust bean gum, fenugreek or other galactomannans against a control. They found 50 trials, with 27 on guar gum, 20 on fenugreek, two on mixed galactomannan and one on locust bean gum. Doses ranged from 50 mg to 100 g per day, and study lengths ranged from 2 hours to 12 months.
What it can’t tell you
- The review cannot show cause and effect because it combines many studies with different designs, doses and populations.
- Most included studies had small sample sizes and some concerns or high risk of bias, so the results may change with better research.
- The evidence was uneven, with far fewer studies on locust bean gum and tara gum, so little can be said about those fibres.
Who paid
- Conflicts
- The authors declare no conflicts of interest.
- Authors work at
- Semmelweis University, Hungary
The paper
- Title
- Fenugreek Is Superior to Guar Gum, Locust Bean Gum and Tara Gum for Metabolic Health: A Systematic Review
- Type
- Systematic review
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Juhász AE, Kara TK, Csajbókné Csobod É, Juhász R (2026). Fenugreek Is Superior to Guar Gum, Locust Bean Gum and Tara Gum for Metabolic Health: A Systematic Review. Nutrients. doi:10.3390/nu18142394Free full textPubMed 42514462DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error