Saffron (Crocus sativus) tepal water extract for lowering meal-time blood sugar in obesity and prediabetes

Acute Effects of Water Extract of Crocus Sativus Tepals on Metabolic Health Parameters in Patients With Obesity and Prediabetes

EARLY_PHASE1 · University of Primorska · NCT07261475

This study tests whether drinking a cold water extract made from saffron tepals before a meal can lower blood sugar after eating in adults with obesity or prediabetes.

Quick facts

PhaseEARLY_PHASE1
Study typeInterventional
Enrollment20 (estimated)
Ages40 Years to 65 Years
SexAll
SponsorUniversity of Primorska (other)
Locations1 site (Izola)
Trial IDNCT07261475 on ClinicalTrials.gov

What this trial studies

This is a randomized, two-visit crossover early-phase 1 trial comparing a single dose of cold aqueous extract of Crocus sativus tepals to cold water, each given 5 minutes before a standardized meal of 100 g white bread. Adults with type I obesity (BMI >30 and ≤35 kg/m2) and/or prediabetes (fasting glucose 6.1–6.9 mmol/L) attend two in-person visits in random order to receive each intervention. Primary measurements include postprandial glycemia and insulin responses, with secondary measures such as resting energy expenditure and blood pressure taken acutely. Participants with diabetes, major medical conditions, pregnancy, celiac disease, electronic implants, or BMI >35 are excluded.

Who should consider this trial

Good fit: Adults with BMI over 30 (but not greater than 35) and/or fasting glucose in the prediabetic range (6.1–6.9 mmol/L), who are not pregnant, do not have diabetes, and have no major medical or gastrointestinal exclusions are ideal candidates.

Not a fit: People with diagnosed diabetes, BMI above 35 kg/m2, celiac disease or gluten intolerance, significant medical or psychiatric illness, pregnancy or lactation, electronic implants, or recent participation in other trials are excluded and unlikely to benefit from this protocol.

Why it matters

Potential benefit: If successful, the extract could offer a simple, low-cost way to reduce post-meal blood sugar spikes and possibly modestly increase resting energy use for people with obesity or prediabetes.

How similar studies have performed: Some small animal and human studies of saffron stigma and other saffron extracts have shown modest metabolic benefits, but use of tepal cold aqueous extract in humans is novel and not well established.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Obesity type I (ITM \> 30 kg/m2) and/or
* Prediabetes (fasting glucose levels 6,1 - 6,9 mmol/L)

Exclusion Criteria:

* Gastrointestinal diseases
* Diabetes mellitus of any type
* Pregnant or lactating, without contraception
* Serious clinical conditions such as cancer, severe infections, severe psychiatric disorders, autoimmune diseases, inflammatory diseases
* Participation in another clinical trial 3 months prior to the study
* ITM greater than 35 kg/m2
* Celiac disease of gluten intolerance
* electronic implant

Where this trial is running

Izola

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: Prediabetes, Obesity & Overweight, Crocus sativus tepals, Glycaemia, Oral glucose tolerance test, resting metabolism, blood pressure, insulin

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.