Long-term research with 100,000 subjects: Higher fruit and vegetable intake can cut death risk by 10%
Eating vegetables more often can cut the mortality risk by nearly 10%, according to the report released on September 7, 2022, by a group of researchers from Yokohama City University (YUC), National Cancer Center Hospital, and other institutes. The data was obtained through the study of nearly 20 years on 100,000 male and female examinees in Japan. It’s the first research in Japan to reveal the relationships between the portion of fruit and vegetable intake and the risk of death, while there are some studies already done in Europe and the U.S. The study reconfirmed the importance of eating more fruits and vegetables.
The researchers used a “cohort study,” a longitudinal study that compares a group of subjects affected by a specific factor and another not affected to see if there are differences in their morbidity and mortality. They began tracking 94,658 examinees, 40 to 69 years old, in 11 regions from Tohoku to Okinawa in 1995 and asked them to state the frequency and the volume of their intakes of 147 items, including 29 vegetables and 17 fruits. Then, they followed their health statuses up until 2018 and confirmed 3,687 died during the study.
In the analysis, the subjects were divided into five groups based on their daily intake of vegetables such as carrots and spinach and fruits such as apples and mandarin oranges. Then, the death rate of each group was calculated. As for fruits, the number of deaths from all causes, including unintentional deaths such as traffic accidents and death from diseases such as diabetes, in the group with the second highest intake (median intake of 243 grams) was 9% lower than the group with the lowest intake (median intake of 41 grams). The number of deaths in the group with the highest fruit intake (median intake of 400 grams) was 8% fewer.
As for vegetables, the number of deaths from all causes in the group with the second highest intake (median intake of 240 grams) was 9% lower than the group with the lowest intake (median intake of 78 grams). Meanwhile, the number of deaths in the group with the highest vegetable intake (median intake of 361 grams) was 7% lower, suggesting eating more vegetables does not simply mean you live longer.
Further analysis of the diet records revealed that the recommended daily intake is 300 grams or more for vegetables and 140 grams or more for fruits. These are lower than the volumes recommended by the Japanese government, but actually, the average intakes in Japan are less than those suggested by the researchers, according to Atsushi Goto, professor of YUC. “I hope the government will utilize our findings when taking initiatives to improve eating habits,” he added.
A survey method that tracks the correlations between specific factors and mortality over a long period. It’s considered to yield highly reliable results. In Japan, the method was used in studies on the life expectancy of atomic bomb survivors and on the lung cancer mortality of smokers and non-smokers.