Last month, I was invited to discuss about “Aging” by storktalks on Den Haag FM.
Here is the link to the facebook live page. I mainly talked about how Japanese culture traditionally view the age.
You can also listen to it on Spotify.
While I was researching about Japan's long life expectancy, I came across with the interesting article titled [The “1975 Diet” and the Secret of Japanese Longevity]. I would like to share it with you.
The group from Tōhoku University conducted several experiments on Japanese diets. I summarized them below but you can also read the full article here.
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1. Japanese vs. American diet: Comparing the the health impact of a typical Japanese diet of the late 1990s with an American diet of roughly the same period using rats and mice
Result:
The Japanese diet group showed;
-increased expression of genes associated with energy, sugar, and lipid metabolism
-decreased expression of stress-response genes.
-less visceral fat stored within the abdominal cavity and lower levels of blood lipids.
The balance between carbohydrates, fats, and proteins was very similar in both diets. The disparities in the test results seem to relate to qualitative differences, such as whether the carbohydrates come from wheat or rice, and whether the protein is primarily from fish and soybeans or beef and pork.
2. Decline of the Japanese Diet: Comparing the the health impact of typical Japanese diets from 2005, 1990, 1975, and 1960 using rats and mice
The Japanese diet has changed with the times, and many believe that the spread of Western foods and eating habits among the Japanese is contributing to a marked increase in such lifestyle diseases as atherosclerosis (a condition where plaque builds up inside arteries) and diabetes.
Result:
The 1975 group had the lowest risk for diabetes and fatty liver.
Compared with the 2005 group, the 1975 and 1990 groups had
-less visceral fat and were less inclined to obesity.
In terms of content, the 1975 diet was higher in legumes, fruit, seaweed, seafood, seasonings, and spices than the other three. It also contained a greater variety of ingredients. At the same time, consumption of juice and sweetened soft drinks was relatively low.
3. Prevention of Aging-Associated Diseases: Comparing the health impact of these diets from different periods on longevity and the aging process using rats and mice
Result:
-At 24 weeks, aging progressed most slowly in the 1975 group.
-By 48 weeks, the 1975 group showed less loss of memory and learning capacity than the 2005 group.
The 1975 and 1990 groups also had longer lifespans on average than the 2005 group, and the 1975 group performed especially well in terms of longevity.
The results of these experiments strongly suggest that the Japanese diets of 1990 and 1975 are healthier for mice than that of 2005.
4-1. Gut Flora and Aging: Comparing the health impact of a typical Japanese diet of today to the health impact of the 1975 diet on moderately obese human subjects
Result:
The 1975 group members experienced;
-Significant decline in the average body mass index and weight along with waist circumference.
-Fall in the levels of LDL cholesterol and rise in the level of HDL cholesterol.
-Decline in the Hemoglobin A1C (used to diagnose and monitor diabetes and pre-diabetes).
4-2. Gut Flora and Aging: Comparing the health impact of a typical Japanese diet of today to the health impact of the 1975 diet on younger non-obese subjects with moderately intense exercises
Result:
The 1975 group members experienced;
-Reduced stress and increased fitness.
Changes found in the 1975 group’s gut microbiota include a smaller population of certain bacteria believed to be associated with a higher risk of lifestyle disease, suggesting that the health benefits of the 1975 Japanese diet may relate to gut flora and their metabolites.
In short, their research to date supports the hypothesis that, when it comes to health and longevity, the 1975 Japanese diet is superior to the typical Japanese diet of today.
5. Secrets of the 1975 Diet: What distinguishes the Japanese diet of 1975 to today’s westernized diet?
a.Variety: The daily menu featured a relatively large number of small dishes.
b.Cooking methods: The top three modes of preparation were simmered, steamed, and raw, followed by boiled and grilled. Frying and sauteeing were somewhat less common. Cooking at high heat, as when frying in oil, can cause nutrients to break down.
c.Ingredients: The 1975 diet was rich in soy products, seafood, tubers, green and yellow vegetables (including pickles), fruit, seaweed, mushrooms, and green tea. Eggs, dairy products, and meat were consumed as well, but in moderation.
d.Seasoning: The skillful use of fermented seasonings (soy sauce, miso, vinegar, mirin, and sake) along with dashi broth helped impart a satisfying flavor to foods without the heavy use of salt and sugar.
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I don't think the Japanese "1975 Diet" is for everybody. For example, soy products may contain antinutrients that reduce the body's ability to absorb essential nutrients. Seaweed is rich in iodine but excessive iodine could adversely affect the thyroid. Moreover, many people do not have gut bacteria to digest seaweed properly. The Mediterranean, low-carb, macrobiotic, Paleo, the Ayurvedic, vegan, gluten-free or other diet methods might be better for you.
But in general, most of people can get benefits from the diet tips listed below;
-greater variety of ingredients
-less high-heat cooking
-less processed food
-less saturated fat
-less sugarly sweets and drinks
-more fiber
-more fermented food
-greater use of fermented seasonings instead of salt and sugar
Please eat & move well and stay healthy!