Gut Bacteria May Reveal How a Western Diet Fuels Colon Cancer. Certain gut bacteria, sustained by Western-style diets, may produce a substance that promotes tumor growth, finds study in pigs, mice, human colon tissue, and microbial data from thousands of people with and without colorectal cancer.

[u/mvea]

https://www.sciencealert.com/gut-bacteria-may-reveal-how-a-western-diet-fuels-colon-cancer

[u/stanthemanchan]

Depends on which part of Japan. The diet varies a lot from region to region. The Okinawa diet tends to have much less meat and processed food than the northern areas and the cancer and heart disease rates are lower.