Safron

Saffron is a spice derived from the flower Crocus sativus and has traditionally been used to flavor food. It has gained scientific attention recently for its potential anti-depressant effects and is available in extract form as a dietary supplement.

Enough evidence has accumulated that we can be confident that saffron has notable antidepressant effects, consistently outperforming placebo. Some studies have tested saffron against reference drugs, such as the SSRI fluoxetine and have found the effects to be comparable, though saffron still has less evidence and less of a real-world track record than many drugs. Additionally, it appears to have anti-anxiety effects, though the evidence for this isn't as strong, and more research in specific anxiety disorders is needed. Some preliminary research suggests that it may help to alleviate the symptoms of premenstrual syndrome, menopause, various inflammatory conditions, and improve sleep, but much more research is needed to be confident in its efficacy for these purposes.

It should be noted that the vast majority of studies have been conducted in Iran, which produces much of the world's saffron. While this should not discredit the results of the studies, and most seem to take reasonable measures to reduce the risk of bias, more replication from other researchers would go a long way toward solidifying saffron's effects. Additionally, much of the depression research from other countries is industry-funded, which carries an obvious conflict of interest.

There's also the possibility of a small effect on blood glucose, LDL, inflammation, liver health, blood vessels, and erectile dysfunction, but these are all of speculative efficacy.