After a long time of trying to publish this, it was finally published today (10 Nov 2026) in the Nutrition Bulletin (Wiley):
Selenium Levels in Brazil Nuts: A Global Review of the LiteratureWe included almost 150 "studies" (data sources) that provided original data on selenium levels in Brazil nuts. Check out the primitive figure that I made for a quick overview of data from different countries (Figure 1).
Most of these were journal articles in English, but we also included some other sources (some national nutrient databases, a dissertation, etc.). Some data sources were in German, Spanish, or (obviously) Portuguese - as most of the data comes from Brazil.
Most Brazil nuts in Europe, however, seem to come from Bolivia - at least in Germany this is the case.
There was much discussion with the editors and reviewers that we should not present Brazil nuts too positively ... Some even suggested that Brazil nut "farming" is harmful to the environment. However, Brazil nuts are largely not farmed but rather gathered (in the capsules that contain the in-shell nuts) in the wild, typically deep inside the Amazon rain forest.
The human rights (and other animal rights) issues associated with Brazil nuts are really interesting, many communities depending on the international trade, for example. This is obviously a very complex topic. Much more interesting that selenium levels in Brazil nuts.
With this article, our Brazil nut trilogy (see the first, radium, and the second, barium) is complete.
But ... the saga continues (!!+?!) ...
P.S.: For the authors' surnames, I made them as searchable and internationally type-able as possible, while trying to be sort of consistent too. Brazilian scientist authors tend to (?) use only their very last surname (often they have half a dozen) as their "English style" surname. This I have often stuck to. Citation manager programmes also mix things up in varied ways (e.g., Souza vs. de Souza), and journals have their own preferences on citation style. Many Eastern European language names (e.g., Polish or Turkish) have letters that English doesn't have, which makes it hard to search for these names. Some accents (diacritical marks) on letters remain, maybe reflecting my own subconscious language biases. ...
Moral of the story: If you can't find your surname, please try an alternative spelling.
P.P.S.: If you have a study with selenium levels in Brazil nuts that we didn't include, please let me know.
Reference:
Christian Koeder, Alexey Vladimirovich Galchenko, Markus Keller: Selenium Levels in Brazil Nuts: A Global Review of the Literature. First published: 10 November 2026 https://doi.org/10.1111/nbu.70079
It will show up on PubMed soon.
