Loma Linda is the only blue zone in the USA, and it is dominated by adventists who are predominately vegetarian. The ones that are not are restricted on what types of meat they can eat (by the religion -- the list is in leviticus).
from the source:
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The people inhabiting Blue Zones share common lifestyle characteristics that contribute to their longevity. Among the lifestyle characteristics shared among the Okinawa, Sardinia, and Loma Linda Blue Zones are the following:[4]
Family - Family is put ahead of other concerns.
No Smoking - Centenarians do not typically smoke.
Plant-Based Diet - The majority of food consumed is derived from plants.
Constant Moderate Physical Activity - Moderate physical activity is an inseparable part of life.
Social Engagement - People of all ages are socially active and integrated into their communities.
Legumes - Legumes are commonly consumed. ------