Japanese research uncovers age and gender influences on dietary patterns

A recent study in Japan has shed new light on dietary patterns among young and middle-aged Japanese individuals. The findings provide insights for personalized nutrition that addresses individual deficiencies, highlight professor Katsumi Iizuka and his team from the Department of Clinical Nutrition, Faculty of Medicine, Fujita Health University.

The analysis found no significant variation in the frequency of consuming individual food items between male and female participants, with the exception of women consuming fruits more frequently than men.

However, when participants were grouped by age and sex, the researchers observed noticeably different dietary patterns pertaining to the intake of meat, fish, eggs, fruits, seaweed, dairy products, vegetables, and potatoes.

“Being aware of the gender- and age-specific differences in dietary patterns and diversity can lead to individualized nutritional improvement for each age and gender group,” says Iizuka.

Age-related preferences

The research team studied anonymized responses from a dietary survey obtained during health checkups of 2,743 Fujita Health University employees. Participants were categorized into four age groups: 20–29, 30–39, 40–49, and 50–59 years.

They filled out a food intake frequency questionnaire that looked at how frequently they consume 10 different foods: meat, fish, eggs, dairy products, soy, green vegetables, seaweed, fruits, potatoes, and oil.

The survey reveals women generally exhibited more diverse dietary patterns compared to men.The questionnaire also covered the frequency of drinking sugar-sweetened coffee, tea, soft drinks, and alcohol.

The survey reveals women generally exhibited more diverse dietary patterns compared to men. Younger men were least likely, while older women were most likely, to follow a meat- or egg-centered dietary pattern that included fruits and dairy products.

Conversely, older men tended to prefer a fish- and fat-centered traditional Japanese diet, while younger women leaned toward plant-based foods such as fruits, vegetables, and potatoes.

Changes over time

The survey demonstrates that differences in dietary patterns between males and females diminished with age, suggesting that dietary preferences change over time.

Dietary diversity and the intake of beneficial foods, including fruits, seaweed, and dairy products, increase with age for both men and women, according to the paper.

This trend may be attributed to generational gaps between adults in their 20s and those in their 40s, with younger adults often living alone, which can influence their food intake and choices, suggest the study authors.

Furthering research

The researchers believe their results may contribute to the understanding of how dietary variations impact gut health and microbiota, as well as the occurrence of diseases such as obesity, diabetes, heart disease, and cancer.

Moreover, this deeper understanding of dietary variations can assist nutritionists tailor their guidance to address individual deficiencies.

“By eating fiber-rich foods and fermented products from a young age, it is possible to reduce the risk of developing heart diseases and cancer,” concludes Iizuka. “Visualizing differences in dietary patterns across generations can improve the general public’s understanding of dietary balance and diversity.”

The findings were published in Volume 17, Issue 13 of the Nutrients journal.