Strong 69/100
Okinawa Centenarian Study
In plain English
More than 900 verified Okinawan centenarians were studied for diet, activity and family history over three decades. The traditional Okinawan diet — sweet potato, vegetables, soy, modest fish — was approximately 96% plant-based by calories and notably low in calories overall ('hara hachi bu', stop at 80% full).
Why it matters
Okinawan centenarians ate a ~96% plant-based traditional diet.
Informs: Blue Zones
Provenance
- Design
- Prospective cohort
- Sample size (n)
- 900
- Follow-up
- 30 years
- Peer-reviewed
- Yes
- Replications
- 2
- Funding
- Public / academic
- Funders
- Japanese Ministry of Health, US NIH
- Institutions
- University of the Ryukyus, Okinawa International University
decades.plus score
A transparent 0–100 weighted sum across six components. Higher scores reflect bigger, cleaner, more replicated work.
Strong 69/100
Caveats
Younger Okinawans have shifted to a Western diet and their longevity advantage is now eroding — a natural experiment in support of the dietary hypothesis.
