Suppose another religion has dietary laws that overlap with those of Judaism. For example, Zoroastrianism prohibits eating all land animals and prohibits eating various kinds of fish and other sea animals depending on conditions such as the species, what time of year it is, and how the animal was raised. Also they are prohibited from eating all insects and have to wash and inspect all fruits and vegetables to make sure there is no bugs in them, also they are strictly prohibited from eating pork just like in Jewish dietary laws https://authenticgathazoroastrianism.org/2012/03/05/zoroastrian-dietary-laws-animal-friendship-and-stewardship/
Would a Jew be allowed to follow such dietary laws, along with the Jewish dietary laws?