Three thousand years of saffron, and where it grows now
Saffron has been cultivated for roughly three and a half thousand years, which makes it one of the oldest ingredients in continuous human use. It has been food and it has been medicine for almost all of that time, often at the same table.
That history is not decoration. It is the reason saffron sits in the food aisle rather than behind a pharmacy counter, and it is the context any modern research on it arrives into.
Where it appears in the written record
Saffron is in both of the great classical catalogues of useful plants. It appears in De Materia Medica, the Greek catalogue of medicinal plants that European practice worked from for centuries, and it appears in the Chinese Compendium of Materia Medica, the corresponding work in that tradition.
Very few ingredients are in both. Fewer still are in both and also in the ordinary cooking of the same regions, which is what makes saffron unusual: it was never only a remedy or only a flavour. Persian food and Persian medicine both used it, and the line between the two was not drawn where we draw it now.
What it does in a kitchen
Persian, Indian, Spanish, Moroccan and Italian cooking all use saffron, and they use it in the same way: a small amount, bloomed in warm liquid, carrying colour and aroma through a whole dish.
It is worth saying plainly that children in those cuisines have eaten saffron for as long as adults have. It is in the rice, the bread and the sweets, not in a separate category kept away from the family table. A food eaten by whole households for three thousand years is a different kind of ingredient from one synthesised in the last thirty.
Where it grows now
Commercial saffron production today is concentrated in a handful of countries: Iran, Spain, Greece and Morocco. The growing conditions are narrow. It needs a dry summer, a cool autumn and a great deal of labour available in a short window, because the flowers open over a few weeks and the stigmas have to come out by hand while they are fresh.
That combination of climate and labour is why the map has barely changed in centuries. The places that grow saffron are largely the places that have always grown it.
Traceable to a field
One of the more satisfying things about the saffron used in modern research is that you can follow it back to a specific place.
The extract that carries most of the published placebo-controlled trials is made from stigmas cultivated in Alborea, in the province of Albacete in Spain, and extracted at a facility in Madrid. The trial authors record it in their methods section rather than leaving it to a marketing page. (Lopresti et al., Journal of Affective Disorders, 2018, PMID 29510352.)
The extraction uses water and no other solvent, which is stated on the product specification. For an ingredient with a long food history, being able to name the region, the facility and the solvent is the modern equivalent of knowing your grower.
What the history is and is not
Three thousand years of use is a genuine signal, and it is worth being precise about what kind of signal it is.
It tells you that saffron is a long established part of the ordinary human diet, eaten at food amounts across many cultures and many centuries, which is exactly why it is regulated and sold as a food.
It does not, on its own, tell you what saffron does. That is what the last two decades of randomised, placebo-controlled trials have been for, and those trials are a separate body of work with their own standards. Tradition earned saffron a place at the table. The research is a different question, asked differently.
Both are true at once, and the combination is rare. Most of what is sold to families has a long history and no research, or research and no history. Saffron has both.
Studies conducted on individual ingredients, not on any finished product. Individual results may vary.