For the US Thanksgiving in November 24, the fasting rules vary with the eparchy and Church. For the Byzantine USA, the canonical fast day is Friday, so it is up to the individual to decide upon the extent and how the fast is kept, in the tradition Monday, Wednesday and Friday are more strict. Also in the fast period is the feast of St. Nicholas, and the Feast of the Conception of St. Anne.
A historical note: “The regulations for the fast were far more lenient than the Great Fast before Pascha. Only Monday, Wednesday, and Friday were days of strict fasting without meat, dairy products or oil (in Slavic countries). On Sundays fish was permitted. Laymen were at first permitted to eat fish on other days, too, until the monastic rigoristic influence prevailed. It is interesting to observe that the famous 12th century Byzantine canonist Balsamon expressed the opinion that it would be enough if laymen fasted only one week before Christmas.”
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