The University of Tokyo researchers conducted a groundbreaking study to quantify the consumption of highly processed foods (HPFs) and their impact on diet quality among Japanese children and adolescents.
Their findings revealed that HPFs make up over one-fourth of the total energy intake among youths, negatively impacting the consumption of healthy foods like fruits, vegetables, and pulses.
Additionally, HPF consumption was found to be linked to increased consumption of confectioneries. This study sheds light on the significant influence of highly processed foods on diet quality and public health, especially among young people. Understanding these findings is crucial for improving overall health and addressing the risk factors for diseases such as Type 2 diabetes.
“Our previous research on HPF consumption in adults in Japan found that higher consumption was negatively associated with diet quality. This significant finding prompted us to investigate whether similar associations exist in younger generations,” said Assistant Professor Nana Shinozaki from the School of Public Health.
“My team and I ran a cross-sectional study, one where many people are assessed in a short space of time rather than fewer people over a long period of time, to understand the association between HPF consumption and overall diet quality among Japanese children and adolescents. We found that higher HPF consumption is associated with poorer diet quality in 1,318 participants aged 3-17 years.”
It’s widely known that this is the first time concrete data has been gathered for this particular demographic. This could prove to be a crucial step in advancing public health initiatives. Researching diets poses challenges due to the lack of precise definitions in many areas.
To address this issue, Shinozaki and her team utilized an existing dietary classification framework from the University of North Carolina at Chapel Hill and employed the Healthy Eating Index-2020 and the Nutrient-Rich Food Index 9.3 to assess diet quality.
According to the UNCCH classification, HPFs are described as “multi-ingredient, industrially formulated mixtures processed to the extent that they are no longer recognizable as their original plant/animal source.”
“The biggest challenge was collecting detailed dietary data, which are essential to identify which foods are HPFs, on eight days over the course of a year from a large sample of about 1,300 individuals,” said Shinozaki. “This process of assessment by researchers, and assessments by participants or parents, was highly burdensome for both participants and investigators due to the need for accurate and consistent recording of dietary intake. Our research could not have been accomplished without the support of research dietitians throughout Japan, who played a crucial role in supporting participants and collecting data.”
The perception of Japan’s national diet as the epitome of healthy eating may be misleading and outdated.
“Professor Kentaro Murakami (of the University of Tokyo) recently found that in a nationally representative sample of Japanese adults, the mean total score of the Healthy Eating Index-2015, a widely accepted diet quality index, was similar to that of average Americans. This finding suggests that the Japanese diet would not be as healthy as expected,” said Shinozaki.
“Wherever you may be, at the individual level, increasing the consumption of unprocessed or minimally processed foods, especially fresh fruits and vegetables, would be helpful. At the societal level, public awareness campaigns, policy, and regulation, or food availability and market changes to promote the reduction of HPFs could be beneficial. Our findings support ongoing efforts to develop nutritional guidelines and public health strategies aimed at reducing the prevalence of diet-related diseases.”
Journal reference:
- Shinozaki N, Murakami K, Kimoto N, Masayasu S, Sasaki S. Highly processed food consumption and its association with overall diet quality in a nationwide sample of 1,318 Japanese children and adolescents: A cross-sectional analysis based on 8-day weighed dietary records. Journal of the Academy of Nutrition and Dietetics, 2024; DOI: 10.1016/j.jand.2024.06.001