Saffron

What saffron is

Saffron is obtained from the dried stigmas of Crocus sativus. Characteristic are the coloring crocins, the bitter picrocrocin and volatile aroma compounds such as safranal. According to the University of Münster, very high-quality saffron can contain up to 30 percent crocin and 15 percent picrocrocin.

Studies and commercial products mostly use standardized extracts. One extract used in several Western studies is called Affron and comes from a Spanish manufacturer; it is typically studied at 28 mg daily, often split into two doses of 14 mg.

How it is supposed to work

Which constituent is active is still open. The research group at the University of Münster summarizes the state of knowledge as follows: crocetin, which is formed from the crocins in the gut, is probably responsible for the neuroprotective effects.

What has been measured in humans is mainly the clinical endpoints, that is, questionnaires on mood, anxiety and sleep. The causal chain in between has barely been quantified, and that sets saffron apart from substances for which the path from intake to effect can be traced.

Mood, anxiety and sleep

The data here are unusually broad for a plant extract. The 2026 meta-analysis by Mahmoudi and colleagues pools 34 randomized studies with 1,769 participants: on the Beck Depression Inventory, the score fell 4.39 points more than under control, on the Beck Anxiety Inventory 5.06 points. The authors rate the evidence as moderate according to GRADE. An older meta-analysis of 23 studies found large effects compared with placebo, Hedges’ g 0.99 for depression and 0.95 for anxiety.

There are also data in people without a diagnosis. In the largest single study to date, 202 adults with low mood received 28 mg of saffron or placebo for 12 weeks. 72.3 percent achieved a clinically meaningful improvement under saffron, 54.3 percent under placebo. In a study with 63 adults with self-reported sleep problems, 14 mg twice daily over 28 days improved the sleep index more than placebo.

Beyond mood, a meta-analysis found relief of premenstrual symptoms with a standardized mean difference of minus 0.64. For the eyes there are 10 smaller clinical studies with 20 to 50 mg daily, including on age-related macular degeneration.

Reports from tradition and practice

In South Asia and the Middle East, saffron is traditionally widespread during pregnancy. A 2026 review describes women taking it to promote the child’s complexion, their own strength and readiness for birth. These are cultural reports, not evidence of efficacy. Low amounts of around 250 mg daily at term have been studied clinically, for example for cervical ripening, while higher doses are associated with labor induction and miscarriage risk.

A single case report describes a 64-year-old man with atrial fibrillation who developed acute bleeding under rivaroxaban and a saffron product; laboratory findings pointed to a platelet disorder, and after stopping both products the bleeding stopped. A single case does not prove a connection, but it fits laboratory data according to which saffron inhibits platelet aggregation in a dose-dependent manner.

What the studies show

Mahmoudi 2026, the largest meta-analysis

Systematic review according to PRISMA with GRADE assessment, including randomized, placebo-controlled studies in adults lasting at least 4 weeks, 34 studies with 1,769 participants. Beck Depression Inventory minus 4.39 points across 14 studies, Beck Anxiety Inventory minus 5.06 points across 6 studies. On the Hamilton depression and anxiety scales and the POMS questionnaire there was no significant effect.

Lopresti 2025, the largest single study

Randomized, double-blind, placebo-controlled study with 202 adults aged 18 to 70 with subthreshold depressive symptoms, 12 weeks, 28 mg of Affron daily. The primary endpoint, the depression scale of the DASS-21, improved more than under placebo, Cohen’s d 0.39. The secondary endpoints did not differ, and the placebo response was large. Two co-authors work for the manufacturer of the extract.

Lopresti 2019, saffron added to an antidepressant

Randomized, double-blind study over 8 weeks with 160 adults with persistent depression despite an antidepressant, 139 evaluable, 14 mg of Affron twice daily. On the clinician-rated MADRS, scores fell by 41 percent versus 21 percent under placebo. On the self-report version of the same scale, by contrast, by 27 versus 26 percent, with no difference.

Shafiee 2025, saffron versus SSRIs

Meta-analysis of randomized studies that compared saffron directly with an SSRI. Across 8 studies no significant difference for depression, across 4 studies none for anxiety. Side effects were less frequent under saffron, risk difference minus 0.06.

Where the data stop

The findings depend heavily on who does the measuring. In the large 2026 meta-analysis, the effect appeared on self-report scales but not on the clinician-rated Hamilton scale; in the 2019 add-on study it was the other way round. The older meta-analysis of 23 studies found signs of publication bias and criticized the lack of regional diversity of the studies, and a 2021 meta-review sees the same risk. Non-inferiority to SSRIs does not mean that saffron can replace an antidepressant: the comparison studies are small and concern mild to moderate cases. Long-term data beyond one year are lacking, and for the eyes and PMS the study base is thin.

Status, approval and legal

As a spice, saffron is a food; extracts are on the market as food supplements. To the knowledge of the research group at the University of Münster, saffron has not yet been assessed by the EMA’s Committee on Herbal Medicinal Products, and in Germany there is no marketing authorization as a medicine for saffron products. There are no authorized health claims, because the assessment of botanical claims has been suspended for years. Quality is a real issue: a systematic review estimates that 20 to 30 percent of saffron traded worldwide is adulterated, 3.5 percent in the regulated EU market. Of 9 saffron food supplements tested in Münster, one probably contained no saffron at all but gardenia extract; the manufacturer withdrew it from the market.

Safety

In usual amounts, saffron is well tolerated. A 2026 systematic review of 102 clinical studies estimates the frequency of side effects at around 17.5 percent, mostly mild, self-limiting gastrointestinal complaints; between 15 and 100 mg daily, side effects did not noticeably increase with dose, and the longest study ran for 12 months. Among the reported side effects, restlessness, irritability and hypomanic symptoms accounted for 32 of 441 reports. Higher amounts have barely been studied: in a study with 200 and 400 mg over 7 days, 400 mg lowered standing blood pressure; blood values changed slightly but remained within the normal range. Because of the platelet inhibition and the case report, caution is advised with anticoagulants. In pregnancy, higher doses are associated with labor induction.

Sources

• Mahmoudi et al., Nutr Neurosci 2026
• Shafiee et al., Nutr Rev 2025
• Marx et al., Nutr Rev 2019
• Lopresti et al., J Nutr 2025
• Lopresti et al., J Psychopharmacol 2019
• Sarris et al., World J Biol Psychiatry 2022 (WFSBP/CANMAT)
• Hasheminasab et al., Health Sci Rep 2026
• Mehdizadeh et al., Crit Rev Food Sci Nutr 2026
• University of Münster, Institute of Pharmaceutical Biology: saffron food supplements
• Alshdefat et al., J Evid Based Integr Med 2026