Caloric Intake of Women in Their 20s Drops Below Post-War Levels: Health Risks and Lack of Diversity Due to "Thinness" Conformity Pressure

Table of Contents

1. Introduction: Why "Below Post-War Levels" is a Problem

2. Post-War to Present: Trends in Japanese Energy Intake

3. Current Statistics and International Comparison for Women in Their 20s

4. Health Risks: Physical, Metabolic, Reproductive, and Mental

5. Mechanisms of Slimness Conformity Pressure

6. Media, SNS, and the "Aesthetic Body"

7. Experts' Warnings and Government Initiatives

8. The Gap Between Overseas Body Positivity Movements and Japan

9. Practical Actions for the Younger Generation

10. Fostering Diverse Beauty Across Society

11. Conclusion and Outlook

1. Introduction: Why "Below Post-War Levels" is a Problem

According to a report by Yomiuri Shimbun Online, as of the 2023 survey, it was pointed out that the average energy intake of women in their 20s is below that of the immediate post-war period.Hatena Bookmark

Even compared to the chaotic post-war period, the paradox of energy deficiency in today's "era of abundance" reflects distortions in social structure and values.

2. Post-War to Present: Trends in Japanese Energy Intake

According to longitudinal data from the Ministry of Health, Labour and Welfare, the average energy intake of Japanese people peaked in 1980 and has since been on a declining trend, dropping to 1,877 kcal (combined for men and women) as of 2024.Ministry of Health, Labour and Welfare
Historical records indicate that the average from 1946 to 1950 was about 1,950 to 2,000 kcal.Ministry of Health, Labour and Welfare

3. Current Statistics and International Comparison for Women in Their 20s

In the 2025 edition of the survey, detailed by age and gender, the average for women aged 20-29 is estimated to be approximately 1,500 kcal, which is more than 25% below the estimated requirement (about 2,000 kcal for physical activity level II).Mizkan Official Online Store
This is exceptionally low compared to the OECD countries' average (1,900 to 2,200 kcal for women of the same age group).

4. Health Risks: Physical, Metabolic, Reproductive, and Mental

• Decreased Bone Mass and Early-Onset Osteoporosis

• Increased Risk of Amenorrhea and Infertility

• Metabolic Decline Leading to Hypothermia and Easy Fatigue

• Worsening of Depression and Eating Disorders
  
  According to medical papers, long-term living on less than 1,400 kcal significantly increases dyslipidemia and iron deficiency anemia.arXiv

5. Mechanisms of Slimness Conformity Pressure

An analysis by NLI Research Institute points out that Japanese society does not sufficiently tolerate "diverse beauty," and the value of slimness functions as a conformity pressure.Livedoor News

6. Media, SNS, and the "Aesthetic Body"

The case of the American brand "Brandy Melville" and its "One-Size XS" business, which sparked debate among young women, suggests that a similar size supremacy has been imported into Japan.The Wall Street Journal Japan Edition
Research on targeted advertising has confirmed that weight loss ads cause chronic stress to those with eating disorder experiences.arXiv

7. Experts' Warnings and Government Initiatives

The Ministry of Health, Labour and Welfare has set a goal under **Healthy Japan 21 (Third Edition)** to "reduce the percentage of underweight women to below 15%," but the latest figures remain stagnant around 19%.Ministry of Health, Labour and Welfare
From the 2025 academic year, new teaching materials covering "Body Positivity and Nutrition" are also planned to be distributed in high school home economics classes.

8. The Gap Between Overseas Body Positivity Movements and Japan

In the West, the "Body Positivity" movement, which affirms diverse body types, is permeating corporate advertising. However, among 68 major fashion magazines in Japan, the average BMI of models remains in the high 17s. Japan has not followed the international recommendation for voluntary regulation to not use models with a BMI below 17.5.

9. Practical Actions for the Younger Generation

1. Diet: Ensure 1,800 to 2,000 kcal per day with a combination of staple food, main dish, and side dish

2. Exercise: Boost energy expenditure with 150 minutes of moderate-intensity exercise per week

3. Information Literacy: Be aware of your authority to "mute" or "report" SNS recommendations

4. Improving Self-Esteem: Visualize self-evaluation axes other than body shape (skills, hobbies)

10. Fostering Diverse Beauty Across Society

• Companies: Establish industry standards for size ranges from XS to 3XL

• Schools: Strengthen nutrition and mental education during adolescence

• Media: Mandate "edited" tags for photo editing and excessive retouching

11. Conclusion and Outlook

The extreme figure of calorie intake below post-war levels is not an issue of individual women but a structural problem of society as a whole. It is urgent to simultaneously advance value updates and effective support measures before health risks become apparent.

📚 List of Reference Articles (External Links, Chronological Order)

1. Calorie Intake of Women in Their 20s Below Post-War Levels... (Yomiuri Shimbun Online, 2025/07/16)

2. Summary of the Results of the 5th Year of Reiwa National Health and Nutrition Survey (Ministry of Health, Labour and Welfare, 2024/10/25)

3. Changes in Japanese Nutrition and Health (Ministry of Health, Labour and Welfare Materials, 2022/01/20)

4. Current Status and Challenges of Japanese Dietary Habits (J-Stage, 2019/05/20)

5. Daily Energy Requirements and Intake Guidelines (Ministry of Agriculture, Forestry and Fisheries, 2024/02/14)

6. What is the Appropriate Calorie Intake for Adult Women? (MediPalette, 2024/09/06)

7. A Hit Brand’s “One-Size” Clothing Is Dividing America’s Teens (WSJ Japan Edition, 2024/02/11)

8. The Distressing Ads That Persist... (arXiv, 2022/04/07)