I’m a nutritionist from Japan, home to the world's longest-living people—here are 5 longevity foods we eat every day

CNBC 3/2/2023 Asako Miyashita, Contributor

I grew up in Japan, where I was taught from a young age to think of food as medicine. My grandmother is 92, and she also credits her longevity to eating the right foods.

Japan is home to some of the world's longest-living people: There are now 90,526 centenarians, or people aged 100 and above. That's more than five times the amount two decades ago, according to a 2022 report from the Ministry of Health, Labour and Welfare.

And the tiny, remote Japanese island of Okinawa has been singled out as having the highest concentration of centenarians in the world.

As a nutritionist who follows a traditional Japanese diet, here are five foods my family and I eat every day to stay healthy and live longer:

1. Japanese sweet potatoes

Hailing from Okinawa, these purple sweet potatoes (called "imo" in Japanese) are often eaten as a snack or dessert.

They are rich in healthy carbohydrates and anthocyanins, a group of antioxidants found in red and purple vegetables that contain anti-aging properties.

Studies have also shown they can help improve blood sugar levels and reduce the risk of cardiovascular disease.

2. Miso soup

The Japanese diet contains a variety of dishes containing fermented foods, and miso soup is a popular one. Miso is a paste made from fermented soybeans and grains.

The probiotics, live bacteria or yeast in fermented foods can help balance our gut health and boost the immune system.

A study found that men and women who ate the most fermented soy (such as miso, tofu and tempeh) had a 10% lower chance of dying early — from all causes — than those who rarely ate these foods.

3. Daikon radishes

Root vegetables are popular in Japanese cooking and provide a host of unique health benefits.

Daikon radishes have been known to help prevent colds and boost the immune system. One radish contains 124% of the daily recommended intake of vitamin C.

Other healthy root vegetables (that may be easier to find in U.S. grocery stores) include carrots, beets, parsnips and turnips.

4. Seaweed

Seaweed is rich in important minerals such as iron, calcium, folate and magnesium.

Eating it every day helps add fiber to my diet. Adequate intake of fiber has been associated with reduced risk of heart disease, stroke, hypertension and type 2 diabetes.

Seaweed also contains antioxidants like fucoxanthin and fucoidan, both of which have anti-inflammatory, anti-aging and anti-cancer properties.

5. Fish

I always include some protein in my daily diet, especially fatty fish like salmon and tuna. The omega-3 fats in fish can help lower blood pressure, lower triglycerides, and ease inflammation.

In Japan, we often say "itadakimasu," which translates to "I humbly receive," before meals to show our appreciation for the animals and farmers. I believe this practice of mindful eating contributes to our health and quality of life.

Asako Miyashita, MS, RDN, CDN, is a certified dietitian and nutritionist, with 20 years of experience in longevity research. Born and raised in Tokyo, Japan, she uses Western and Eastern perspectives in her work to help improve her clients' health. She has been a guest lecturer at several universities and organizations, including the Japanese Medical Society of America. Follow her on Instagram @miasako.

Don't miss: