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Japanese Traditional Foodstuffs Hold the Secret to Longevity

November 7, 2016

Traditional Japanese cuisine: great for your health!

Japan has one of the highest life expectancies in the world: over 80 for both men and women. While various factors contribute to this, including improved medicine and health care, diet is crucially important.
A typical Japanese meal consists of rice, miso soup, a main dish and two side dishes-a combination referred to as One Soup, Three Dishes. Rice is the staple food and is a source of energy. Soup supplements liquid intake requirements. And the food dishes combine a wide variety of items, making it easy to enjoy a well-balanced and nutritious meal.
Such traditional Japanese cuisine - washoku - consists mainly of seafood and vegetables, so it’s low in both fats and calories. Added to that are the health benefits of traditional foodstuffs such as blue-backed fish, soybean products and fermented foods. These items help prevent lifestyle-related diseases.

Bluefish are rich in DHA and EPA

Blue-backed fish (or bluefish) refers to a category of fish with silver blue skin. Those used in Japanese cuisine include horse mackerel, sardines, mackerel and Pacific saury. If you don’t eat much seafood, you may not know what a blue-backed fish looks like. But even so, you’re probably familiar with tuna, especially if you’ve tried melt-in-the-mouth otoro and chutoro, the especially fatty portions of the fish. Tuna, too, is a bluefish.
Japan, being surrounded by the sea, has long relied on ocean resources for food. Bluefish, in particular, were a popular source of inexpensive but tasty seafood. Nowadays, with catches in decline, bluefish may not be as cheap as before, but it is still very widely eaten.
Back in the days when meat-eating was rare in Japan, people relied on seafood to supplement their intake of protein and calcium. Recent research has shown that seafood is rich in other nutrients as well. Bluefish in particular contains an abundance of the omega acids DHA (docosahexaenoic acid) and EPA (eicosapentaenoic acid).
DHA and EPA differ from the fatty acids found in beef, pork and other meat.
Meat contains saturated fatty acids which, when taken in abundance, increases the level of cholesterol and neutral lipids: factors in hardening of the arteries.
Bluefish, on the other hand, contain the polyunsaturated fatty acids DHA and EPA, which are omega fatty acids - also called n-3 fatty acids - that reduce cholesterol and neutral lipid levels, and help prevent blood clotting.
DHA, in particular, is highly effective in preventing blood clotting and hardening of the artery walls, both of which are associated with heart attacks and strokes.
EPA, in addition to improving concentration and helping to prevent dementia, enhances the development of the brain and nervous system. It is an important nutrient for both for growing children and adults.

Soybean products and isoflavones

Soybeans are the main ingredients in such essential items in Japan as tofu, natto, miso and soy sauce. Soybeans are rich in the polyphenols called isoflavones.
Polyphenols are compounds found in plants. They have strong antioxidant properties that protect cells from the damage caused by free radicals, thereby acting against both aging and cancer. In addition to being an antioxidant, isoflavones exert an effect similar to that of female hormones, and may help prevent and reduce menopausal disorders and osteoporosis.
Isoflavones also contain oleic acid, linoleic acid and alpha-linoleic acid, which strengthen artery walls and prevent hardening of the arteries.
Because they contain practically as much protein as beef, soybeans are often referred to as "meat from the fields."
In Japan, they have long been a key source of protein going back to the times when there was no custom of eating meat. Today, with the rise in obesity, they have become an important source of low-fat, low-calorie protein.

Fermented foods bursting with healthy nutrients

Several years ago, Japan saw a huge surge in sales of a natural seasoning called shio koji. It has now won acceptance as a versatile seasoning and is becoming popular internationally as well. On the US west coast and in New York, it’s known as Creamy Koji Sauce and its ability to draw out the umami flavor of ingredients has been noted.
Koji is made by inoculating steamed grains such as rice, wheat or soybeans with a type of mold. Then the grain is fermented under strictly controlled temperature and humidity conditions. Koji mold is essential to the production of a wide range of Japanese seasonings and alcoholic beverages: miso, soy sauce, mirin, sake, shochu and amazake.
Many other fermented products are made in Japan. Natto is made by fermenting soybeans with natto bacteria(Bacillus subtilis var. natto). Dried bonito flakes, one of the key ingredients for making dashi, is also a fermented product, and nukazuke are vegetables pickled in fermented rice bran. Fermented foods are part and parcel of Japanese cuisine.
The fermented foods commonly found outside Japan include yogurt, cheese and sauerkraut. But there must be very few individual countries that can rival Japan in terms of the sheer variety of fermented foods eaten on a daily basis.
Historically speaking, fermented products were developed in Japan to prevent foods from spoiling in a warm, humid climate. Before the development of refrigerators and freezer units, harnessing the power of fungi to process and ferment products was the best way to keep foods edible for a long time.
Fermentation also offered unexpected benefits. In addition to enriching flavor, it generated various health-enhancing components. They include amino acids that boost umami and the production of vitamins, enzymes that promote digestion, and oligo sugars that enhance the effects of lactic acid bacteria.
Natto, for example, contains several times more vitamins than soybeans. Nattokinase, an enzyme found only in natto, helps to dissolve blood clots and is believed to be an effective blood thinner that prevents hardening of the arteries.
Nukazuke pickles are rich in beneficial lactic acid bacteria that help maintain a healthy intestinal environment and regulate bowel movement. A healthy intestinal environment is key to a strong immune system.

People in the old days may not have had any scientific understanding of the properties found in fermented foods, but experience revealed their health benefits. Fermented products tend to have a strong smell that may seem pungent. But considering the benefits, it’s definitely worth giving them a try!
Bluefish, soybean products and fermented items: three key factors in the long and healthy life enjoyed by so many people in Japan.

Text: Manami Shigenobu

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