In 2022, Japan was the country with the highest average life expectancy in the world. Every 25 years, the Japanese life expectancy increases by at least 4 years, with a very low rate of illness. By 2020, the average life expectancy of Japanese people had reached a record high for both genders (87.74 years for women and 81.64 years for men).

According to World Health Ranking data, Japan ranks 152nd in the world for stroke-related mortality, 134th for breast cancer mortality, 153rd for liver disease mortality, and 166th for lung disease mortality.

These figures are out of a total of 172 countries, meaning Japan’s mortality rates from these diseases are among the lowest in the world. Therefore, the Japanese are regarded as symbols of healthy and long living, admired and studied by many nations.

In fact, the secret to the Japanese longevity does not lie in luxury but is closely linked to their daily diet. The Japanese particularly favor three types of vegetables, considering them “longevity foods”: amaranth, garlic chives, and sweet potato leaves.

Fortunately, in Vietnam, these vegetables are also common, though not everyone understands their full health benefits.

1. Garlic Chives

For the Japanese, garlic chives are a healthy vegetable that greatly enhances well-being. In Eastern medicine, they are described as pungent, slightly sour, and warm in nature, often referred to as the “vegetable of the kidneys,” particularly beneficial for men’s vitality. Containing anti-inflammatory compounds even stronger than antibiotics, garlic chives can also be consumed daily as a natural remedy for gynecological infections in women.

Garlic chives are also rich in vitamins and crude fiber, which help improve intestinal motility, treat constipation, and prevent colon cancer. Additionally, they promote blood circulation, dissolve blood stasis, and support detoxification. Eating garlic chives regularly in winter and spring can help ward off colds, boost stamina, and enhance yang energy.

Despite their many nutritional benefits, garlic chives should not be eaten excessively at once, as they may upset the digestive system. The recommended intake is 100–200 grams per meal.

When cooking, chop them finely and stir-fry quickly over high heat. Overcooking will make them mushy and unpleasant while also degrading the beneficial sulfides.

2. Sweet Potato Leaves

The Japanese are especially fond of sweet potato leaves. In Japan, they are sold at high prices and hailed as a “longevity vegetable” thanks to their valuable nutrients. They are considered a vitamin treasure, containing 10 times more vitamin B2 than sweet potato tubers, along with high amounts of fiber, vitamin B6, vitamin C, and antioxidants.

According to Eastern medicine, sweet potato leaves are neutral in nature and slightly sweet, often used as a herbal remedy under different names such as cam thử and phiên chử. They are believed to treat spleen deficiency, poor appetite, and also help detoxify and clear internal heat.

Regular consumption helps cleanse internal organs, especially beneficial for intestinal detox due to their cooling properties. Their fiber content stimulates bowel movements and supports detoxification of organs such as the liver and kidneys.

Sweet potato leaves also protect eyesight, prevent cardiovascular disease, lower blood pressure, stabilize blood sugar, and strengthen immunity.

Rich in vitamin K, they reduce the risk of cancers such as colon, prostate, nasal, oral, stomach cancers, as well as heart disease. Research even shows that liver cancer patients who supplement with sufficient vitamin K daily can improve their liver function.

However, people with diarrhea or weak digestion should be cautious, as the high fiber makes them harder to digest. Those with gastritis or low blood sugar should also avoid them.

Sweet potato leaves should be blanched before stir-frying to reduce oxalic acid, which otherwise binds with calcium in the body to form kidney stones. Despite their many benefits, they should be eaten only about twice a week.

3. Amaranth

Amaranth is a staple vegetable in the Japanese daily diet. In Eastern medicine, it is sweet, cooling, and non-toxic.

It is called a “longevity vegetable” because it is rich in fiber, which supports digestion, protects the intestines and stomach, keeps the bowels moist, and ensures smooth intestinal movements.

Amaranth is also one of the vegetables with the highest iron content among fresh greens. Its high iron helps increase hemoglobin and red blood cell production, making it especially beneficial for people with anemia.

Moreover, it is abundant in calcium—easily absorbed by the body—playing a vital role in the development of bones and teeth, maintaining heart function, and preventing muscle cramps. Amaranth also contains twice as much carotene as most grains, providing essential nutrients and contributing to overall health.

Because of these outstanding nutritional values, amaranth is considered a food that promotes longevity.