Photo/Illutration Fermented natto beans (Asahi Shimbun file photo)

People who eat fermented soy-based foods such as "natto" and "miso" on a daily basis reduce the risk of dying from a stroke or heart attack by 10 percent, according to a long-term study by the National Cancer Center.

Researchers at the NCC started monitoring the health of about 90,000 adults, both male and female, in 1995, and spent 15 years looking into individual cases on average.

The team members interviewed each individual to find out what they ate each day, and categorized them into five groups based on their consumption of soybeans and fermented soy-based food.

The team analyzed the data after excluding the effects of other food items and drugs to reduce blood pressure.

The group of males and females who consumed about 50 grams of fermented soy-based foods on a daily basis lowered their risk of death from certain diseases by about 10 percent compared with the group with the lowest consumption of this type of food.

Natto generally is sold in 50-gram packages.

The survey finding of a reduced death risk from certain diseases was particularly pronounced among female participants.

When natto consumption was higher, the death rate caused by abnormalities in blood circulation, such as stroke and heart attack fell.

Norie Sawada, analytical epidemiology section chief at the NCC, said, “Fermented soy-based food retains minerals and isoflavone, which are beneficial to human health.”

The survey findings were reported in the British Medical Journal on Jan. 29. (https://www.bmj.com/content/368/bmj.m34)