Blue Zones are five regions of the world with the highest concentrations of centenarians (people who live to 100+). Their diets share striking commonalities.

The five Blue Zones:

• Sardinia, Italy
• Okinawa, Japan
• Loma Linda, California (Seventh-day Adventists)
• Nicoya Peninsula, Costa Rica
• Ikaria, Greece

Common dietary patterns:

• Plant-predominant — 95% of calories from plants
• Legumes — beans, lentils, chickpeas eaten daily
• Whole grains and tubers as staples
• Minimal meat (Okinawans eat pork sparingly at feasts only)
• Very little sugar or processed food
• Moderate caloric intake (Okinawans practice "hara hachi bu" — eat to 80% full)

Key insight: Legumes are the single most consistent longevity food across all Blue Zones.

Reference:

Wikipedia: Blue zone

https://en.wikipedia.org/wiki/Blue_zone