For details, see Selenium & Brazil Nuts.
Article: (2016) Four Brazil Nuts Once a Month…. Dr Greger says:
In view of this video by Dr Greger, some people choose to consume 4 Brazil nuts on the 4th of every month :)
(3 mins) Transcript. Dr Greger's summary: "A single serving of Brazil nuts may bring cholesterol levels down faster than statin drugs and keep them down even a month after that single ingestion."