Brazil nuts are among the most radioactive foods there are, because of the radium they absorb from the soil.
Why it is true
The deep roots of the Brazil nut tree pick up radium from Amazonian soil, and the nuts can contain up to a thousand times more than other foods. Even so, the dose is so small that eating a few nuts is perfectly safe.
Source: Oak Ridge Associated Universities
Would you rather be asked first?
This is the reading side of the site, so the answer is in the sentence above — that is the whole point of it. Test yourself works the other way round: the question comes on its own, and the fact and the explanation only appear once you have answered.
