A Japan study suggests, based on the results of a longitudinal analysis, that a traditional Japanese diet or TJD seems to reduce breast cancer incidence and mortality.
The traditional Japanese diet or TJD mainly consist of
a staple food such as – steamed rice or soba, ramen, or udon noodles, soup (miso,
vegetable, or noodle), main dish (fish, seafood, tofu, or natto with small
amount of meat, poultry, or egg), and side dishes (vegetables, wild plants,
seaweed, and raw or pickled fruit).
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Photo: Traditional Japanese Diet | InStyleHealth |
Researchers evaluated the longitudinal correlation
between TJD score and the incidence and mortality of breast cancer in an ecological
study. Experts obtained food supply and breast cancer incidence and mortality
by country from an international database.
The TJD score by country was calculated from nine food
groups, with the total score ranging from -9 to 9: higher scores indicated
greater adherence to a traditional Japanese diet.
Experts analyzed longitudinal correlations of interaction
between TJD score and fiscal year on breast cancer incidence and mortality in
139 countries with populations of 1 million or more. They also evaluated the
correlations utilizing four linear mixed-effects models with different
adjustment covariables.
Throughout 1990 – 2017, many countries with high traditional
Japanese diet (TJD) scores revealed lower distributions of breast cancer incidence
and mortality.
With longitudinal analysis utilizing a linear mixed-effect
model controlled for socioeconomic and lifestyle covariables, the interaction between
TJD score and fiscal year revealed a significant association with a decrease in
breast cancer incidence and mortality.
The researchers said that the traditional Japanese
diet is considered one of the important factors of health and longevity in
Japanese people, while noting that breast cancer is still the most common
cancer among women across the globe.
Source: Eur J Clin Oncol 2021;75:929-936