Researchers followed over 93,000 Japanese adults for nearly 19 years to see how their eating habits affected how long they lived. They found that people who ate more like traditional Japanese people—with lots of rice, vegetables, fish, and soy—lived longer and had fewer heart problems. Interestingly, when researchers added coffee and dairy products to the traditional Japanese diet pattern, the health benefits got even better, especially for men. This suggests that the modern Japanese diet, which includes some new foods while keeping healthy traditional foods, might be one reason Japanese people live so long.

The Quick Take

  • What they studied: Whether eating like Japanese people eat helps them live longer and prevents heart disease
  • Who participated: 93,049 Japanese men and women aged 45-74 years old with no serious health problems at the start, followed for an average of 18.9 years
  • Key finding: People who ate more like traditional Japanese people had about 15-20% lower risk of dying from any cause, and the risk was even lower when coffee and dairy were included in the diet pattern. Men saw bigger benefits than women.
  • What it means for you: If you want to live longer and reduce heart disease risk, eating more like Japanese people do—with lots of vegetables, fish, rice, and soy—may help. This is especially true if you also drink coffee and include some dairy products. However, this doesn’t mean you need to eat only Japanese food; it means including more of these healthy foods in your regular diet.

The Research Details

This was a long-term follow-up study where researchers tracked the same group of Japanese people over nearly 19 years. At the beginning, they asked participants detailed questions about what they ate and drank. Researchers then created a scoring system to measure how closely each person followed a traditional Japanese diet pattern. They looked at 13 different foods and drinks that are typical in Japan, like rice, miso soup, seaweed, vegetables, fish, soy products, and green tea. Later, they created updated versions of the score that included coffee and dairy products, since these have become more common in Japan. Throughout the study, researchers kept track of who got sick and who died, and what caused their deaths.

This type of long-term study is important because it follows real people in their everyday lives over many years, which gives us better information than short-term studies. By tracking actual deaths and causes, researchers can see real health outcomes rather than just measuring things like cholesterol levels. The study also looked at how the Japanese diet has changed over time, which is important because what people eat today is different from what they ate 20 years ago.

This study is considered high quality because it included a very large number of people (over 93,000), followed them for a long time (nearly 19 years), and carefully recorded what they ate and what happened to them. The researchers used proper statistical methods to account for other factors that might affect how long people live, like age, smoking, and exercise. The study was published in a respected nutrition science journal. However, because this study was done only in Japan, the results might not apply exactly the same way to people in other countries with different genetics and lifestyles.

What the Results Show

People who followed the traditional Japanese diet pattern most closely had about 15-20% lower risk of dying from any cause compared to those who followed it least closely. This benefit was seen in both men and women. The benefits were even stronger when researchers added coffee and dairy products to the diet pattern—men who followed this updated pattern had even lower death rates. Heart disease deaths were particularly reduced in people who ate more like traditional Japanese people, with men seeing about 20-25% lower risk. The longer people followed these eating patterns, the more protection they seemed to get. These benefits stayed strong even after researchers accounted for other important factors like smoking, exercise, and body weight.

The study also looked at deaths from cancer and other causes, though the results were less clear for these. The traditional Japanese diet pattern showed some protective effect against cancer deaths, but the benefit was smaller than for heart disease. Interestingly, the benefits were generally stronger for men than for women, though both groups benefited. The study found that the newer version of the Japanese diet score—which includes coffee and dairy—worked better than the traditional version, suggesting that the Japanese diet has naturally evolved to include foods that are even healthier.

Previous research has shown that traditional Japanese eating patterns are healthy, but this study is important because it shows that the modern Japanese diet—with added coffee and dairy products—may be even better. This is different from what some people might expect, since they might think that adding modern foods to a traditional diet would make it less healthy. Instead, this research suggests that the Japanese diet has naturally improved as it has changed. The study also confirms what other research has found: that eating patterns matter more than any single food, and that the combination of foods in the Japanese diet works together to provide health benefits.

This study was done only in Japan with Japanese people, so the results might not apply exactly the same way to people of other backgrounds or in other countries. The study asked people about their diet only once at the beginning, so researchers couldn’t track how eating habits changed over time. People who eat healthier diets often also exercise more and have other healthy habits, so it’s hard to know if the diet itself is causing the benefits or if it’s the overall healthy lifestyle. The study also couldn’t prove that the diet causes longer life—it only shows that people who eat this way tend to live longer. Additionally, the study included mostly middle-aged and older adults, so results might be different for younger people.

The Bottom Line

If you want to improve your health and potentially live longer, try eating more like Japanese people do: eat more rice, vegetables, seaweed, fish, soy products (like tofu and miso), mushrooms, and fruits. Drink green tea and coffee. Reduce very salty foods and processed meats like beef and pork. This recommendation has moderate to strong evidence behind it, especially for heart health. You don’t need to eat only Japanese food—just try to include more of these foods in your regular diet.

This research is most relevant for middle-aged and older adults (45+) who want to reduce their risk of heart disease and live longer. It’s especially relevant for people of Japanese descent, though the healthy eating pattern may benefit people of other backgrounds too. People with heart disease, high blood pressure, or high cholesterol should definitely pay attention to this research. However, if you have specific health conditions or take medications, talk to your doctor before making big changes to your diet. This research is less clear about benefits for younger people or for preventing specific types of cancer.

You probably won’t notice dramatic changes in how you feel right away, but eating this way may help your heart health within a few weeks to months. The real benefits—living longer and preventing serious diseases—take years to show up. Think of this as a long-term investment in your health rather than something that will help you feel better tomorrow. If you have high blood pressure or high cholesterol, you might see improvements in blood tests within 2-3 months of eating this way.

Want to Apply This Research?

  • Track your daily intake of the 15 key foods: rice, miso soup, seaweed, pickles, vegetables, non-salty fish, salty fish, green tea, fruits, soy products, mushrooms, coffee, dairy products, and salt from seasoning. Rate your adherence to the Japanese diet pattern on a scale of 1-10 each day based on how many of these foods you ate.
  • Start by adding one new Japanese food to your diet each week. Week 1: add seaweed to your meals. Week 2: try miso soup. Week 3: add tofu or another soy product. Week 4: drink green tea daily. Continue building until you’re regularly eating most of these foods. Use the app to log which foods you ate and get reminders to try new ones.
  • Track your diet weekly and calculate your Japanese diet score. Also monitor how you feel—energy levels, digestion, and any changes in blood pressure or cholesterol if you check these. Set a goal to reach a certain diet score within 3 months, then 6 months. If possible, get blood work done annually to see if your cholesterol and blood sugar are improving.

This research shows an association between eating like Japanese people and living longer, but it does not prove that the diet causes longer life. Individual results vary based on genetics, overall lifestyle, and other health factors. This information is for educational purposes and should not replace advice from your doctor or registered dietitian. If you have existing health conditions, take medications, or are considering making significant dietary changes, consult with your healthcare provider first. Pregnant women, children, and people with specific medical conditions may need different dietary guidance.