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30 May 2025

Unraveling Rising Mortality: Statistical Insights from Japan and International Comparisons

Department of Internal Medicine, Osaka Dental University, 8-1 Kuzuhahanazonocho, Hirakata 573-1121, Osaka, Japan
Healthcare2025, 13(11), 1305;https://doi.org/10.3390/healthcare13111305
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Abstract

Since the onset of the COVID-19 pandemic, Japan has experienced a significant rise in mortality, with excess deaths surpassing historical projections. Statistical data indicate a sharp increase in mortality rates from 2021 onward, attributed to COVID-19, aging demographics, cardiovascular diseases, and malignancies. Preliminary 2024 data suggest continued excess mortality, fueling public debate. This review analyzes national and municipal mortality trends using official Japanese statistics and comparative data from South Korea, the U.S., and the EU. Findings reveal a sharp mortality rise post-2021 in Japan and South Korea, while Western nations experienced peak deaths in 2020, followed by declines. The review explores contributing factors, including potential vaccine-related adverse effects, declining healthcare access, pandemic-induced stress, and demographic shifts. Notably, older adults’ reluctance to seek medical care led to delayed diagnoses, treatment interruptions, and preventable deaths. Although some argue that declining COVID-19 vaccination rates in 2023 may have contributed to rising mortality in 2024, available data suggest a multifactorial causation. Japan’s rapidly aging population, coupled with increasing mortality and declining birth rates, presents profound social and economic challenges. A nuanced approach, avoiding simplistic causal claims, is crucial for understanding these trends. This review highlights the need for a sustainable societal framework to address demographic shifts and improve healthcare resilience. Future pandemic strategies must balance infection control measures with mitigating unintended health consequences to ensure a more adaptive and effective public health response.

1. Introduction

Since the onset of the coronavirus disease (COVID-19) pandemic, rising mortality rates in Japan have become a topic of concern. In particular, reports indicate an increase in excess mortality, defined as the difference between observed deaths and the number expected based on historical data and statistical models [1]. Mortality rates have risen significantly since 2021, posing a major public health challenge. Statistical data up to 2022 suggest that, in addition to COVID-19, factors such as senility, cardiovascular diseases, and malignant neoplasms have contributed to this increase [2]. Moreover, the continued long-term monitoring of excess mortality and other quantitative data beyond 2022 remains essential [3]. In February 2025, nationwide and municipal-level statistical reports on mortality for 2024 were released. Meanwhile, discussions on social media platforms such as X have highlighted growing concerns over the renewed increase in deaths throughout 2024 (Table 1). The increase in mortality during the COVID-19 pandemic has been reported in countries other than Japan [4,5,6,7]. Even after the acute phase of the COVID-19 pandemic subsided, mortality rates in Japan have not decreased. In 2022, they rose again, in 2023 there was a slight decrease or plateau, and in 2024, a trend of rising mortality rates has been observed again.
Table 1. URLs of the social media reporting the increase in the number of deaths in Japan (accessed on 27 May 2025).
A recently published short opinion article discusses the relationship between COVID-19 vaccination and excess mortality in Japan [8]. This article describes the sharp increase in excess mortality in Japan following the emergence of the Omicron variant. Hypotheses regarding the potential association between mRNA vaccination and excess mortality include adverse effects such as myocarditis, autoimmune diseases, and cancer, as well as immune suppression due to repeated vaccinations. However, this article does not provide direct evidence demonstrating a causal relationship between mRNA vaccines and excess mortality. Instead, it outlines possible contributing factors and concludes that, due to insufficient research and data, the true cause remains unclear.
To clarify the relationship between vaccination and excess mortality, studies directly investigating the correlation between mRNA COVID-19 vaccination and excess mortality in Japan are necessary. However, as of now, no studies have comprehensively examined this association.
This review first examines trends in mortality counts and crude death rates over the past decade across Japan and its four major cities (the 23 wards of Tokyo, Yokohama, Osaka, and Nagoya), comparing these trends with those observed in other countries. It then explores potential factors contributing to the rise in mortality in Japan since 2021. Finally, the author offers insights into Japan’s future as the country enters an era of unprecedented population decline.
While this review article references numerous online sources, the author wishes to emphasize that these citations are intended solely to confirm objective facts and are not meant to defame or criticize any specific individual or group.

2. Development and Efficacy of mRNA Vaccines: A Scientific Assessment of COVID-19 Protection

mRNA COVID-19 vaccines work by delivering mRNA encoding the viral spike protein into the body, prompting cells to produce the antigen and induce an immune response. Their rapid development was enabled by pre-existing mRNA technology research, the prioritization of funding and regulatory processes during the pandemic, and the concurrent execution of large-scale clinical trials. Extensive clinical trials and real-world data have confirmed their high efficacy, particularly in preventing severe disease, as well as their safety, with rare but minimal risks of adverse effects [9].
Japan’s Ministry of Health, Labour, and Welfare, along with related academic societies, strongly recommends additional vaccinations in the fall and winter of 2024 for the elderly and those at high risk of severe disease [10]. They maintain the stance that the benefits of COVID-19 vaccination far outweigh the risks. Numerous studies worldwide support the efficacy of COVID-19 mRNA vaccines, and infectious disease experts continue to recommend vaccination based on these findings.
Compared to unvaccinated individuals, vaccinated individuals have been shown to have a reduced risk of hospitalization and long-term symptoms [11]. In South Korea, vaccinated individuals had lower non-COVID-19 mortality rates compared to unvaccinated individuals [12]. In the Netherlands, the 2023 COVID-19 XBB.1.5 vaccine was associated with reduced hospitalizations and ICU admissions due to COVID-19 [13]. Even in breakthrough infections, vaccination has been shown to suppress household transmission [14]. In Japan, a report indicated that Omicron breakthrough infections in individuals with three or more vaccine doses or prior infections had a lower frequency of systemic symptoms [15]. Vaccination has also been associated with a lower risk of post-acute sequelae of COVID-19, with a third dose further reducing risks of heart failure, arrhythmia, cardiac arrest, pulmonary embolism, and new dialysis compared to two doses [16].
Many studies have reported the beneficial effects of vaccination on long-term symptoms. Booster doses have been shown to mitigate severe disease and post-acute sequelae [17,18]. Pre-infection vaccination has been strongly associated with a reduced risk of being diagnosed with long-term COVID-19 complications [19]. A systematic review and meta-analysis have also confirmed that vaccines reduce post-COVID-19 conditions [20]. Additional reports suggest that the post-COVID-19 syndrome risk is lower among previously vaccinated individuals compared to unvaccinated individuals infected with the Omicron variant [21].
The updated 2023–2024 COVID-19 vaccines have demonstrated protective effects against hospitalizations caused by XBB and JN lineages, providing a rationale for promoting new vaccine formulations [22]. The BNT162b2 XBB vaccine offers statistically significant additional protection against various COVID-19 outcomes. However, older vaccine formulations provided little to no long-term protection against hospitalization, irrespective of the dose number or vaccine type, reinforcing the need for updated vaccinations [23]. The relative effectiveness of ancestral-strain mRNA vaccines against Omicron infections has been shown to be higher than that of viral vector and protein subunit vaccines [24].
Accordingly, the U.S. Advisory Committee on Immunization Practices (ACIP) has recommended COVID-19 vaccination for all individuals aged six months and older using FDA-approved or authorized vaccines for the 2024–2025 season [25].
However, mRNA vaccines have been reported to cause more adverse reactions compared to Novavax’s protein-based COVID-19 vaccine (NVX-CoV2373) [26]. A Japanese study suggested that while COVID-19 mRNA vaccines are generally safe, there was a potential trend of increased pulmonary embolism following the first dose [27].
Despite ongoing discussions regarding COVID-19 vaccination, a substantial proportion of the elderly population in Japan had received booster doses up until 2023. However, the uptake of booster vaccinations in 2024 has declined considerably.

5. Excess Mortality and COVID-19 Vaccination

Preliminary mortality data for each municipality in January 2025 were released in February 2025, revealing a significant increase in deaths compared to the previous year. This sharp rise has become a topic of widespread discussion (Table 1).
A study in the United Kingdom has reported that the standardized mortality ratio (SMR) for all-cause mortality is higher in COVID-19 vaccinated individuals compared to unvaccinated individuals [41]. Opponents of COVID-19 vaccination argue that this surge in excess mortality is a direct consequence of the harmful effects of COVID-19 vaccines [42,43]. Infectious disease experts promoting COVID-19 vaccination appear in newspaper advertisements sponsored by vaccine manufacturers, continuing to advocate for booster doses [10]. However, it has been pointed out that the number of cases approved for compensation under the COVID-19 vaccines injury relief system, including deaths, far exceeds the total for all other vaccines combined over the past more than 40 years [44]. The number of deaths officially acknowledged under the Immunization Health Damage Relief System approaches 1000. It is anticipated that some may argue that the high number of compensation cases is due to the overwhelmingly large number of COVID-19 vaccines recipients. However, it has also been claimed that the incidence of adverse events is significantly higher for COVID-19 vaccines compared to influenza vaccines, despite both being widely administered [45].
Given such reports, it is understandable that the general public may grow increasingly distrustful of COVID-19 vaccines.
While the possibility that long-term effects of mRNA vaccines may have contributed to increased rates of cardiovascular diseases or immune dysfunction cannot be ruled out, multiple factors need to be considered [8]. After vaccination, cases of herpesvirus [46], varicella-zoster virus infections [47], autoimmune diseases [48,49], thrombotic thrombocytopenia [50], nephrosis [51,52], nephritis [53,54], myocarditis, and pericarditis [55,56,57,58,59,60] have been reported. Notably, a significant rise in deaths was already evident in 2021, the year COVID-19 vaccinations began. Some researchers have speculated that the increase in mortality observed from 2024 to 2025 could be a delayed manifestation of vaccine-related adverse effects or long-term complications.

6. Other Contributing Factors to Increased Mortality

However, in addition to potential vaccine-related impacts, several other factors may have contributed to the rise in mortality. A key demographic factor is Japan’s aging population—by 2024, the baby boomer generation will have reached 75 years and older, an age range associated with naturally rising mortality rates. Healthcare access issues may have also played a role, including increased strain on medical institutions and a decline in healthcare-seeking behaviors. Japanese older adults have traditionally sought medical care more frequently than those in other countries. However, following the COVID-19 pandemic, an increasing number of elderly individuals refrained from seeking medical attention. As a result, cases emerged in which the treatment of previously managed diseases was interrupted, regular screenings were not conducted, making early detection difficult, and, in some instances, patients were unable to access appropriate medical care after disease onset, leading to preventable deaths. These effects may still persist today. Furthermore, this reluctance to seek medical care likely contributed to insufficient prevention and early intervention for conditions such as cancer, cardiovascular diseases, and cerebrovascular diseases.
The implementation of COVID-19 countermeasures aimed at minimizing interpersonal contact led to a decline in routine health check-ups among older adults, which is likely to have had a direct causal relationship with the observed increase in overall mortality. During the pandemic, elderly individuals increasingly refrained from seeking medical care due to concerns about infection risk. As a result, reductions in cancer screening participation and increases in the self-discontinuation of prescribed medications were observed. In a survey asking about “diseases for which patients were unable to seek care due to the impact of COVID-19”, 59.3% of care managers in Tokyo responded affirmatively. Among these, the most frequently cited conditions were “lifestyle-related diseases” (27.9%), followed by “dementia” (23.3%) and “dental diseases” (19.8%) [61]. These trends suggest that the health management of older adults and the healthcare delivery system were adversely affected during the pandemic, highlighting the need for targeted interventions going forward.
The adverse effects of delayed diagnosis and treatment have also been observed in patients with cardiovascular diseases requiring emergency care. Alarmist messaging by some infectious disease experts contributed to heightened public anxiety, which in turn led to delays in the diagnosis and treatment of more severe diseases. In Japan, the COVID-19 pandemic had a notable impact on patients with ST-elevation myocardial infarction (STEMI). Following the COVID-19 pandemic, primary PCI was performed significantly less frequently, and the incidence of mechanical complications resulting from ST-elevation myocardial infarction (STEMI) increased. Failing to seek immediate medical attention and waiting at home when experiencing heart attack symptoms may worsen outcomes for patients with STEMI [62]. A decrease in hospital admissions, delays in seeking care, and treatment initiation were observed [63]. The door-to-balloon time (DTBT), a critical indicator of timely reperfusion through primary percutaneous coronary intervention (PCI), was significantly prolonged during the pandemic [64,65].
Reperfusion therapy for acute ischemic stroke was also impacted by the COVID-19 pandemic. During the state of emergency, the number of stroke admissions decreased, and the time from hospital arrival to imaging and thrombolysis was longer compared to the period before the pandemic [66]. Thus, the fear of contracting COVID-19 has led to delays in the treatment of other life-threatening emergency conditions.
Furthermore, the pandemic was associated with a reduction in cancer screening and early detection. In Japan, population-based cancer screening participation declined by approximately 10–30% during the pandemic [67]. As of 2024, although the number of cancer screenings showed a partial recovery in 2021, levels have not returned to pre-pandemic baselines, except for endoscopic gastric cancer screening. This continued decline raises concerns about potential delays in cancer diagnosis and increases in cancer-related mortality, warranting close monitoring [68]. Notably, a transient decrease in the proportion of early-stage colorectal cancer diagnoses was also observed following the declaration of a state of emergency. Although some reports noted that treatment outcomes at individual medical institutions were not necessarily worsened, the cumulative impact of widespread disruption to the healthcare system likely contributed to adverse effects at the population level.
Moreover, frailty caused by the COVID-19 pandemic is also a problem due to older adults being afraid of contracting COVID-19, which has caused them to refrain excessively and stay at home. The aftermath of the pandemic has led to heightened stress levels and reduced routine health check-ups, potentially exacerbating chronic diseases.
It is well established that physical activity enhances antiviral immunity and may serve as a countermeasure against immune senescence [69]. Conversely, it has been suggested that reduced physical activity due to self-isolation and other infection control measures may have the opposite effect [70].
Several reports from Japan have examined the relationship between the COVID-19 pandemic and frailty and sarcopenia in older adults. In the first year of the pandemic, both physical activity and social engagement significantly declined, as indicated by previous studies [71,72]. The prevalence of frailty among older adults steadily increased from the pre-pandemic period through the first and second years of the pandemic [73]. A retrospective cohort study found that behavioral restrictions during the pandemic contributed to the loss of skeletal muscle mass in older patients with type 2 diabetes. These findings underscore the importance of interventions, such as exercise promotion and adequate nutritional intake, to prevent muscle loss [74]. Additionally, both older men and women experienced a decline in trunk muscle mass during the pandemic, suggesting the progression of sarcopenia. Muscle loss was also associated with increased risks of falls and cognitive decline in older men [75]. It has also been reported that healthy and active older adults require specific strategies to maintain trunk muscle mass in order to prevent so-called “corona-frailty” [76]. Furthermore, corticosteroid use in the treatment of COVID-19 has been identified as a risk factor for the development of osteonecrosis of the femoral head [77] and may also contribute to the onset of diabetes [78]. These findings suggest a potential link between COVID-19-related changes and the increased risk of cardiovascular events and mid-term mortality.
The reasons why Japanese older adults refrained from visiting doctors are believed to be largely influenced by the fear of infection risk, especially due to the widespread public health campaign during the early days of the 2020 pandemic. Following the recommendation of Professor Nishiura of Hokkaido University, who was a member of the Cluster Response Team at the Ministry of Health, Labour, and Welfare at the time, there was a major push to reduce contact with others by at least 70%, and as much as possible by 80%. Other factors, such as overcrowding in medical facilities, mental stress, and the desire to avoid placing additional burdens on the healthcare system, may have also contributed.
The author has previously highlighted concerns that prioritizing infection control may have delayed the diagnosis of other diseases [36], and that strict patient isolation protocols may have hindered flexible responses in clinical settings, potentially lowering the overall quality of medical care [79]. These can be considered indirect adverse effects of COVID-19 infection control measures.
During the COVID-19 pandemic, social and psychological stress was exemplified by symbolic incidents of discrimination and prejudice against healthcare workers. Heightened fear and uncertainty surrounding infection led, in some instances, to a perception of healthcare professionals as potential sources of contagion. In Japan, several emblematic cases of such discrimination have been reported. These include children of healthcare workers being denied access to daycare centers and schools, healthcare professionals being refused taxi rides, and even being pressured by neighbors to move out of their residences. Such experiences caused significant psychological distress among healthcare workers, including symptoms consistent with post-traumatic stress disorder (PTSD), and had substantial social repercussions [80]. Another symbolic and socially significant issue was the imposition of excessive visitation restrictions in the name of infection control. These restrictions often exacerbated anxiety and distress among patients’ families, who increasingly required information and emotional support from medical staff. In neonatal intensive care units (NICUs), families reported disruptions in bonding with their infants and disturbances in family dynamics. For healthcare providers, visitation restrictions introduced ethical dilemmas and increased burdens related to communication and provision of social support [81].
While some may argue that the absence of infection control measures would have led to a higher number of direct COVID-19 deaths, it is deeply ironic that the extensive efforts, financial costs, and sacrifices made for infection control may have ultimately contributed to increased stress levels, a decline in routine health checkups, the progression of frailty in older adults, and an overall rise in mortality.

9. Examining Japan’s Rising Mortality Rate: An International Comparison and Contributing Factors

Based on our previous considerations, the author aims to explore the reasons for the notable increase in Japan’s mortality rate from an international perspective, particularly in comparison with Western countries.
One possible explanation is Japan’s super-aged society. Japan has a higher proportion of elderly individuals than other countries, which naturally contributes to a greater prevalence of underlying health conditions, potentially leading to an increased mortality rate.
A key factor is the direct impact of COVID-19 itself. In Japan, there was a significant increase in COVID-19-related deaths among the elderly, particularly from the latter half of 2022 onward. In contrast, Western countries experienced their peak infections between 2020 and 2021, suggesting that Japan’s peak was delayed.
Another consideration is the potential contribution of adverse events related to COVID-19 vaccination, particularly thrombotic events and cardiovascular diseases, to increased mortality. While vaccination rates declined in Western countries after 2022, Japan continued booster vaccinations, especially among the elderly, with many receiving six to seven doses. Additionally, mRNA vaccines were predominantly used in Japan, whereas other countries also incorporated protein-based vaccines. Notably, the Novavax protein-based COVID-19 vaccine (NVX-CoV2373) has been reported to have fewer side effects compared to mRNA vaccines [26]. To assess the impact of vaccines, an urgent investigation is needed to analyze the correlation between Japan’s excess mortality rate and vaccination rate since 2022.
The impact of COVID-19 policies should also be considered. Japan implemented strict infection control measures—including mask mandates, restrictions on outings, and behavioral limitations—for an extended period. This prolonged adherence to restrictive measures may have contributed to increased frailty and immune decline among the elderly. In contrast, Western countries lifted restrictions earlier, allowing for natural exposure to the virus and potentially facilitating immunity acquisition.
Healthcare and social system factors may also have played a role. In Japan, the excessive emphasis on infection control may have overwhelmed medical institutions, leading to delays in the diagnosis and treatment of cancer and chronic diseases. Given that the peak of COVID-19 infections in Western countries occurred earlier, their healthcare systems may have recovered sooner. Furthermore, in Japan, the strain on medical resources resulted in increased cases of emergency transport difficulties, delaying treatment for myocardial infarction and stroke. In other countries, emergency medical services unrelated to COVID-19 may have resumed more promptly.
Lastly, the prolonged implementation of strict infection control measures in Japan had significant economic and social repercussions. The resulting economic downturn, rising inflation, and stagnation of income growth likely deteriorated the quality of life (QOL) for many individuals. Notably, the suicide rate increased, particularly among young adults and middle-aged men. In contrast, other countries experienced swifter economic recovery and the resumption of social activities.
Regarding suicide, the increase in suicide rates since 2020 has emerged as a significant social issue in Japan, with a particularly pronounced impact on women. During the second wave of the pandemic (July–October 2020), the monthly suicide rate increased by 16%, with a sharper rise among women (37%) and children and adolescents (49%) [94]. Although the rise in female suicides in Japan during the pandemic has been attributed to factors such as worsening economic conditions, financial insecurity, and social isolation, studies have shown that the increase occurred across various occupations, motives, and age groups [95]. Among men, suicide rates increased in 2022 based on age-standardized mortality rates (ASMRs), marking the first increase since 2009, following the Lehman shock (Figure 10A). In particular, suicide rates were higher in 2022 among males aged 50–59 and those aged 80 and above [96]. Data obtained from an independent website on age-standardized suicide mortality further support this trend, demonstrating an increase in suicide rates among women in 2020 (Figure 10C) and among men in 2022 (Figure 10B), consistent with the patterns observed in Figure 10A. When considering the overall population (Figure 10D), the previously observed declining trend in age-standardized suicide mortality has ceased following the onset of the pandemic. Notably, there has been a marked acceleration in the increase in age-standardized mortality due to suicide among individuals under 20 years old since the beginning of the pandemic (Figure 10E). This trend is consistent with the increase in all-cause age-standardized mortality rates observed among minors (Figure 4D), suggesting the need for further investigation into the social and psychological challenges faced by children and adolescents.
Figure 10. Trends in age-standardized mortality due to suicide. (A) Age-standardized mortality rates for suicide across Japan [2]. (B) Age-standardized mortality counts for suicide among men. (C) Age-standardized mortality counts for suicide among women. (D) Age-standardized mortality counts for suicide in both sexes. (E) Age-standardized mortality counts for suicide among individuals under 20 years of age, in both sexes. (B–E): The regression line was constructed based on data from the period up to 2019 [33].

10. Japan’s Declining Population and Its Implications

Although deaths in Japan have risen significantly, the birth rate has sharply declined. Japan has entered an era of extremely low birth rates and increasing mortality. Since the onset of the COVID-19 pandemic, mortality rates have exceeded initial projections, highlighting a more severe population decline than previously anticipated. Measures such as providing support for child-rearing and considering the acceptance of immigrants are being explored to address the declining birthrate, but their effectiveness is likely to be limited. This demographic shift poses substantial challenges, including economic stagnation, diminished international influence, difficulties in maintaining social infrastructure and welfare systems, and security concerns. These issues have profound implications for Japanese society. Whether or not we choose to acknowledge this reality, we must confront it objectively. Moving forward, the key challenge is to develop a sustainable society based on a model of shrinking equilibrium—one that accommodates population decline without economic and social collapse, while integrating economic and social planning with demographic trends.
In Japan, where the majority of food and energy supplies rely on imports, some argue that maintaining a population of 120 million will become increasingly difficult as the country’s economic contraction and decline are anticipated in the future, potentially leading to a loss of the financial capacity to sustain such imports. Japan is the first major nation in modern history to experience such a rapid population decline. Low birth rates and an aging population make demographic decline a pressing issue not only in Japan but also in other developed countries. In contrast, many developing nations continue to struggle with rapid population growth. The global challenges of food and energy crises remain pressing, and population decline may help reduce environmental burdens. From an environmental conservation perspective, a shrinking population is not necessarily an entirely negative phenomenon. By pioneering a model for a society adapting to population decline, Japan can offer valuable insights for building a sustainable future.

11. Conclusions

The rising mortality in Japan, particularly since the onset of the COVID-19 pandemic, represent a significant public health concern. The analysis of nationwide and municipal mortality trends highlights a clear pattern of increased deaths beginning in 2021, which persisted through 2023 and shows projections for continued elevation in 2024. While COVID-19, alongside factors like cardiovascular diseases and cancer, has undoubtedly played a role, other complex factors, including the aging population, healthcare access issues, and possible long-term effects of COVID-19 vaccinations, must also be considered.
There are some limitations in this review article. The author was unable to calculate age-standardized mortality rates due to a lack of access to age-stratified mortality data. Consequently, it was necessary to rely on previously published studies and make secondary use of figures from an independent website that draws on official statistics published by public institutions. It is also possible that age-stratified mortality data for 2024 have not yet been released. The continued monitoring of age-standardized mortality rates beyond 2025 will be important. It is necessary to conduct further research, including cohort studies comparing mortality rates between vaccinated and unvaccinated groups to demonstrate a true causal relationship between COVID-19 vaccination and mortality, studies comparing international excess mortality data and examining correlations with vaccination rates, and research analyzing differences in mortality rates based on the presence or absence of booster vaccinations.
Moreover, increases in mortality are likely influenced by multiple factors, including age, vaccination status, access to healthcare, social security systems, and life expectancy. Future studies should employ multivariable analytical approaches that take these contributing factors into account.
The challenges posed by Japan’s declining birthrate and aging population further complicate the situation, necessitating the careful examination of the interconnected demographic and public health issues.
Despite the ongoing debate surrounding the causes of increased mortality, it is essential to adopt a balanced, data-driven approach to understanding the factors at play. A cautious and objective analysis of the available data, without resorting to extreme positions on either side of the vaccination debate, is crucial for developing appropriate public health responses. Japan’s demographic decline, while presenting significant challenges, also offers an opportunity for the country to pioneer sustainable solutions for managing population change, potentially providing valuable insights for other nations facing similar issues. Moving forward, Japan must confront these demographic and public health challenges with strategic, evidence-based planning to ensure a stable and sustainable future.

Funding

This research received no external funding.

Acknowledgments

I would like to express my deep gratitude to Hiroyuki Morita, whose insights were highly informative during the preparation of this manuscript, and to Kenji Fujikawa, a city councilor of Koganei City, Tokyo, for permitting the use of figures from the statistical site.

Conflicts of Interest

The author declares no conflict of interest.

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