Skip to main content
Evidence-Based Supplement Research
Evidence-Based Supplement Research

Bitter gourd (Momordica charantia L.) supplementation for twelve weeks improves biomarkers of glucose homeostasis in a prediabetic population.

  • 2025-05
  • Journal of ethnopharmacology 347
    • Jurriaan J Mes
    • Maartje van den Belt
    • Sandra van der Haar
    • Els Oosterink
    • Teus Luijendijk
    • Koen Manusama
    • Lotte van Dam
    • Tessa de Bie
    • Renger Witkamp
    • Diederik Esser

Study Design

Type
Randomized Controlled Trial (RCT)
Sample size
n = 38
Population
prediabetic subjects (two studies: n=30 and n=38)
Methods
Two randomized controlled trials: a 4-week cross-over (n=30) with 2.4 g/day freeze-dried bitter gourd juice vs cucumber control, and a 12-week parallel (n=38) with 3.6 g/day freeze-dried whole fruits vs matched control
Duration
4 weeks and 12 weeks

Ethnopharmacological relevance

Bitter gourd (Momordica charantia L.) is known for its ability to reduce parameters of diabetes, but its effects on prediabetic subjects have been scarcely studied.

Aim of the study

To assess the efficacy of Momordica charantia supplementation in a prediabetic population on markers of glucose homeostasis.

Methods

Two randomized controlled studies were conducted to assess the effect of bitter gourd supplementation in a prediabetic population. Study 1 was a 4-week cross-over intervention trial (n = 30), with freeze-dried bitter gourd (BG) fruit juice (2.4 g/day) or a cucumber-based control product (CC). Study 2 was a parallel trial (n = 38) lasting 12 weeks, with freeze-dried whole fruits (3.6 g/day) or a cucumber-based matched control supplement. Effects on fasting plasma glucose (FPG), insulin, HbA1c, fructosamine, postprandial glucose after an oral glucose tolerance test, and several safety biomarkers were also analyzed in both trials before and after the interventions.

Results

In Study 1, no significant differences were found between the bitter gourd and placebo interventions. However, a reduction in FPG in subjects with higher baseline values were found following bitter gourd supplementation, which was not observed in the control group. However, in Study 2, we observed significant reductions of FPG (p = 0.014), fasting insulin (p = 0.007), and HOMA-IR (p = 0.003) after a 12-week intervention with the bitter gourd supplement. In addition, between treatment analysis resulted in significant effects on FPG levels (p = 0.026) and HOMA-IR (p = 0.045) with no significant effects on other biomarkers related to glucose metabolism. On average, bitter gourd intervention reduced FPG by ∼0.05 mmol/L per week, whereas FPG remained unchanged following placebo. In both studies, there were no indications of health risks or side effects from consumption of the supplements.

Conclusion

Results suggest that supplementation with bitter gourd fruit can have positive effects on fasting plasma glucose and insulin among prediabetic subjects when provided over an extended period of at least 12 weeks.

Research Insights

  • significant reductions of FPG (p = 0.014), fasting insulin (p = 0.007), and HOMA-IR (p = 0.003) after a 12-week intervention with the bitter gourd supplement.

    Effect
    Beneficial
    Effect size
    Small
    Dose
    3.6 g/day
  • significant reductions of FPG (p = 0.014), fasting insulin (p = 0.007), and HOMA-IR (p = 0.003) after a 12-week intervention with the bitter gourd supplement.

    Effect
    Beneficial
    Effect size
    Small
    Dose
    3.6 g/day
  • significant reductions of FPG (p = 0.014), fasting insulin (p = 0.007), and HOMA-IR (p = 0.003) after a 12-week intervention with the bitter gourd supplement.

    Effect
    Beneficial
    Effect size
    Small
    Dose
    3.6 g/day
Back to top