1 Introduction

Immediate-onset natural disasters frequently result in food security challenges. The Great East Japan Earthquake of 2011 left 470,000 people homeless, and 8.4 million servings of food were consumed in the week following the earthquake (Nakazawa and Beppu 2012). Disasters’ impact on the demand side severely disrupts residents’ access to food, procurement routes, and food handling due to infrastructure failures. Meanwhile, the slow implementation of humanitarian aid and government relief, alongside paralyzed supply routes, highlights the importance of fostering food security preparedness at the individual and household levels. This is because individuals and households are basic units on the frontline, and are able to help reduce risks. Unsafe food (due to unprepared or available prepared food being destroyed by the disaster) and the failure to cook food properly can lead to secondary or unintended health challenges (food-borne diseases) after a disaster, which may cause more harm. Although these risks can be mitigated through the implementation of policies by local departments or disaster governance by communities, food preparedness and disaster risk reduction knowledge at the household level still play an important role in disaster mitigation (Hiatt et al. 2022; Oktari et al. 2020).

Numerous factors influence household food security in disaster-threatened areas. Firstly, the characteristics of a household, such as population composition, economic status, and living environment, may influence that household’s food utilization methods and storage quantities. The demographic composition of a household influences both the quantity and variety of food that its residents require (Chakalian et al. 2019). Moreover, the economic status of a household determines the types and quantities of food its inhabitants can purchase. Regions less prone to disasters may not implement additional disaster preparedness measures (Daimon et al. 2023). Secondly, household food security is influenced by disaster risk reduction management (Shukri et al. 2023). A household’s increased proactive response to disasters and its possession of diverse disaster coping strategies imply greater adaptability, prompting consideration of food security and preparation during such events. Thirdly, understanding disaster prevention is crucial for households, as it directly relates to the sustainability of their preparedness efforts, involving threat comprehension and collaborative work. The education level of the household head may impact disaster preparedness decisions, while the involvement of household members in disaster activities can enhance decision-making quality (Zheng et al. 2024). Examples of such activities include regular learning sessions and discussions on disaster preparedness, as well as checking the availability of disaster relief supplies. Establishing more social connections also facilitates smooth information exchange, as it enables individuals to share information about local disaster preparedness arrangements through community activities, thereby promoting understanding of disaster household food security. In Japan, these social connections have played a crucial role in reducing the risk of disasters (Cabinet Office, Government of Japan 2023). The said connections are fostered through neighborhood associations, known as Chonaikai or Jichikai, organizing events, conducting disaster prevention drills, and engaging in activities to enhance local communities. Summarily, the multidimensional factors impact household food security in various ways, making it challenging to systematically establish connections with multiple factors.

Within disaster risk reduction, resilience serves the main function of integration, helping connect and integrate these multiple factors (Béné et al. 2016). At the household level, resilience is often considered as a household’s responsive capacity, because the dynamic factors of a household in disaster risk reduction, such as learning and decision-making, are essential when it comes to enhancing the sustainability of the household’s disaster resilience. In disaster-prone Japan, a comprehensive disaster prevention system has been established at national, local, and household levels. Residents enhance disaster awareness and preparedness through community events and assistance from local authorities, enhancing overall resilience (Cabinet Office of Disaster Management in Japan 2014). These disaster risk reduction activities can effectively increase human resilience capacities to reduce disaster effects (Ahmad and Afzal 2019; Shah et al. 2018). Household food security is often included as a disaster resilience component, and it is assumed that high resilience indicates that household food security is guaranteed. However, the resilience level is not indicative of the corresponding food security capacity (Ansah et al. 2019). This is because the household food system involves multiple components and reflects a household’s livelihood outcomes. Moreover, some household disaster risk reduction interventions may not effectively enhance household food security in the short term. For instance, short-term economic assistance to families may not lead to sustainable resilience improvement in the long term. Therefore, it is necessary to differentiate between resilience concepts and dimensions of household food security, exploring their relationship to enable policymakers to develop more detailed intervention measures to enhance household food security.

Since Alinovi et al. (2008, 2010) developed a conceptual framework, researchers have investigated the relationship between resilience and household food security in the context of disasters. According to our review of the literature, firstly, studies have focused on how household resilience impacts household food security in the context of disasters (Smith and Frankenberger 2018; Murendo et al. 2020), although most have not explored how resilience mitigates household food insecurity before disasters, nor have they addressed how resilience affects the food security conditions of households during the preparedness phase. The Sendai Framework highlights the importance of preparedness and prevention in the pre-disaster period. Therefore, this contributes to a growing body of literature on relevant topics and provides empirical evidence for the connection between disaster resilience and household food security in the pre-disaster preparedness phase. Secondly, most studies have developed their food security measurements by adopting existing food indicators, such as the Household Food Insecurity Access Scale (HFIAS)Footnote 1, Food Consumption Score (FCS)Footnote 2, and Dietary Diversity Score (DDS)Footnote 3 (Bahta and Myeki 2022; D’Errico et al. 2018; Vaitla et al. 2020). However, these indicators are designed to measure hunger- or undernutrition-related issues that do not fit certain disaster scenarios. For instance, people in Japan enjoy relatively good welfare conditions and most people do not have to worry about food. However, food supply shortages or food destruction due to frequent natural disasters may drastically impact a household’s food security conditions. Thus, an indicator based on disaster characteristics, consistent with the context of the study site, could describe household food security. This helps provide profiles of disaster resilience and potential household food security in the pre-disaster period. Lastly, Béné et al. (2012) argued that common food security indicators (FSIs) cannot capture the potential disruptions that could affect multiple food security dimensions. According to the Food and Agriculture Organization of the United Nations (FAO), food security includes availability, accessibility, utilization, and stability, all of which can be impacted by disasters. Therefore, exploring the relationship between household disaster resilience and food security also helps capture how the different disaster resilience dimensions mitigate disasters to affect these different household food security dimensions.

In sum, the present study explores the relationship between disaster resilience and potential household food security. This paper can contribute to the current knowledge about (1) understanding the potential household food security of disaster-prone households by considering three of the four food security dimensions, (2) comprehending the disaster-prone households’ resilience by considering three types of resilience capacities, and (3) assessing the relationship between the three disaster resilience capacities and three food security dimensions among disaster-prone households. A survey was conducted with the residents of Kumamoto Prefecture in Japan, where natural disasters have occurred in the past decade. Following this, the relationship between residents’ disaster resilience and potential household food security was analyzed using a Tobit model.

2 Conceptual model and research hypotheses

2.1 Conceptual model

Studies have discussed the conceptual framework and links between disaster resilience capacities and household food security. These frameworks consider the household unit as a proxy of the food system and the FSI as the result of the system’s internal activities (Ansah et al. 2019). Resilience is conceptualized as an internal characteristic, the result of adaptation activities and the joint action of various types of capital, establishing a link between food security and these attributes through pathways. Our study follows the same logic, although none of these frameworks focus on the linkage between the various resilience capacities and multiple household food security dimensions, thus overlooking their different impacts. Therefore, our framework explores the relationships between disaster resilience capabilities and household food security dimensions; the scenario discussed in this study is the potential situation before disasters (Fig. 1). This framework comprises three parts. The first introduces the constituent elements and categories of household disaster resilience capacity. The second part presents three potential household food security dimensions in the pre-disaster period and their constituent elements. The third part is represented by the middle lines in Fig. 1, which present hypotheses for the relationship between disaster resilience capacities and household food security.

Fig. 1
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Conceptual model

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2.2 Hypothesis development

2.2.1 Absorptive capacity and potential household food security

Absorptive capacity describes a system’s stability or rehabilitating capacity when exposed to change (Béné et al. 2012). The concept has emerged from numerous coping strategies or household attributes. Households adopt these strategies or attributes to mitigate the impact on their livelihoods (Béné et al. 2016). Earlier studies have identified the important role of assets, savings, and income in cushioning disaster shocks and helping households recover rapidly. Households with financial security have additional money to invest in non-essential products such as emergency food supplies and disaster kits (Onuma et al. 2017). Moreover, disaster-related insurance also helps a household to rehabilitate effectively and reduce post-disaster stress (Eriksen and Vet 2021). These factors mitigate the impact of disasters on households. However, household characteristics such as size and the proportion of vulnerable people affect the buffering and rapid recovery of households. Large households are more likely to need food and medical support during an emergency (Chakalian et al. 2019). Additionally, elderly and senior adults, children, and people with disabilities may require more assistance during crises, thereby exposing a household to danger for a longer period (Lee et al. 2022). These vulnerable populations reflect the weak coping capacity in households. Based on this, it can be assumed that household stability has a positive correlation with food preparation, tool acquisition, and food usage. Therefore, the a group of hypotheses is as follows.

H(a)

There is a positive correlation between absorptive capacity and the three household food security dimensions (H1a-availability, H2a-accessibility, H3a-utilization).

2.2.2 Adaptive capacity and potential household food security

Adaptive capacity refers to a household’s flexibility in using coping strategies without making qualitative changes to the way it operates (Béné et al. 2012). It is generated by considering the various coping measures households use when faced with disasters. Firstly, diversifying a household’s access to information enables the acquisition of more information regarding the disaster’s magnitude and the preparation of an effective response, while it also expands the household’s options for accessing information about food supply locations (Shah et al. 2018). Secondly, family communication can raise awareness of the risks and encourage protective behavior in terms of preparing for hazardous events or provide warnings and trigger particular behavioral responses during such events (Hansson et al. 2020). Additionally, families use several other disaster risk reduction measures, such as acquiring information about the route to evacuation sites, preparing first-aid kits for disasters, and replacing damaged houses. All of these strategies reflect residents’ flexibility to adjust and respond to disasters. Summarily, we argue that the diversity and flexibility of households’ strategies based on changing contexts help them adapt in times of disaster, and that these disaster prevention strategies indicate households’ potential disaster preparedness, which can indirectly or directly influence the preparation and utilization of household food security strategies. Based on this, we formulate the b group of hypotheses as follows.

H(b)

There is a positive correlation between adaptive capacity and the three household food security dimensions (H1b-availability, H2b-accessibility, H3b-utilization).

2.2.3 Transformative capacity and potential household food security

Transformative capacity represents the ability to learn and reflect to adjust the system so that it is no longer vulnerable to similar disruptions (Ansah et al. 2021). At the household level, this capacity includes families’ activities aimed at making permanent and fundamental changes to the household system’s performance or structure (Béné et al. 2016). This ensures that households are more likely to survive a future disaster. Regarding the learning dimension, in Thailand, households whose members live in risk-prone areas and participate in disaster training or drills are more willing to adopt countermeasures (Muttarak and Pothisiri 2013). In Pakistan, individuals with lower education levels may lack an understanding of potential coping strategies and face high risk during disasters (Shah et al. 2018). These findings suggest that learning ability or experiences can change people’s perceptions of disasters and their attitudes toward them. Regarding social engagement and decision pluralism, the community plays a crucial role in all disaster timelines, such as providing preparation guidance during the pre-disaster period, coordinating evacuation, rescue, and relief during disasters, and assisting recovery in the post-disaster stage (Patterson et al. 2010). In summary, transformative capacity enables households to fundamentally alter their response to future disasters, implying a higher disaster awareness level and more effective choices when preparing for disasters. As such, this study formulates the c group of hypotheses as follows.

H(c)

There is a positive correlation between transformative capacity and the three household food security dimensions (H1c-availability, H2c-accessibility, H3c-utilization).

3 Research methods and data

3.1 Study area

Kumamoto Prefecture in Japan is located on the island of Kyushu (Fig. 2). Given the occurrence of multiple catastrophic disasters, Kumamoto Prefecture is recognized as a disaster-prone area. On April 14, 2016, 228 people were killed and 2,753 injured in house collapses and landslides caused by the Kumamoto Earthquake, which had a maximum magnitude of 7.3. Electricity, gas, water, and other essential facilities were affected, and 480,000 households were without electricity during the most severe stage of the earthquake damage (Cabinet Office of Disaster Management in Japan 2017). According to the Japanese Cabinet Office, the economic damage caused by the earthquake could amount to as much as 3.8 trillion yen (Cabinet Office, Government of Japan 2017). Moreover, during heavy rains in Kumamoto from July 3 to 8, 2020, 65 people were killed, two people went missing, and 51 people were injured, as the rains caused river flooding and sedimentation when the seasonal rain front expanded from central Chugoku, stagnating in Kyushu (Kumamoto Prefecture Government 2021a). Additionally, the heavy rains damaged 7,300 houses, railroads, highways, other infrastructure, and all industries. Total economic losses in Kumamoto Prefecture are expected to reach 522.2 billion yen (Kumamoto Prefecture Government 2021a). The frequent occurrence of mega disasters is the reason we selected Kumamoto Prefecture as our study site.

Fig. 2
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Map of the study area. (Note: The map provides only a general description of the impact of the two different disasters. The red circle indicates the range of the 2016 Kumamoto Earthquake, and the precipitation distribution map shows the approximate rainfall distribution from July 3 to 4, 2020.)

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3.2 Sampling and household survey

In total, 544 household samples were randomly drawn from Kumamoto Prefecture through an Internet survey (GMO RESEARCH) from March 16 to March 29, 2022. The Internet survey company allowed us to select participants from their registered respondents to avoid duplicate samples in the same household. We requested that the demographic characteristics of the sample be selected according to the local population characteristics. The sample size was calculated based on Rao’s Sample Size Calculator, accepting a calculation error of 5% and a confidence interval of 95% (Raosoft, Inc 2004). With Kumamoto Prefecture’s total population of 7.2 million (Kumamoto Prefecture Government 2021b) and a response distribution of 50%, the calculated sample size should be 384. As such, a sample size of 544 is sufficient to represent the overall population. Individual registered respondents were interviewed online using Google Forms. The questions pertained to the basic characteristics of residents, livelihood and savings, disaster-related preparation, and potential household food security contributions. Five samples were rejected owing to incomplete or missing information. Finally, 539 household samples were selected.

3.3 Variables

3.3.1 Potential household food security

The main dependent variable is potential household food security, and the unit of analysis is the household. As per the suggestions of the FAO, Centers for Disease Control and Prevention (CDC) and Federal Emergency Management Agency (FEMA), we created an integrated FSI. Since food security stability is largely disrupted by disaster damage, this study only focuses on three food security dimensions: food availability, food accessibility, and food utilization. Ten questions were adopted to measure three household food security dimensions (Table 1). Two questions on food availability indicated a household’s food and water supply. During a mega disaster, power supply disruptions could result in poor electricity connectivity, contamination of groundwater, and eventual issues in accessing food supplies. Thus, it is crucial to make provisions for household food security until humanitarian aid arrives. Four other questions on food accessibility asked about households’ access to food sources. This concept highlights households’ ability to access food resources through various sources (e.g., purchasing vs. obtaining food and water from nature). Moreover, four questions on food utilization examined aspects related to knowledge and awareness actions. This dimension covers the sanitation and sufficiency of food and water. Houses may experience water damage from floods or tsunamis, while mold or sewage might contaminate the house, ruining prepared food and drinking water. Furthermore, power and gas outages may cut off power to the refrigerator and prevent individuals from cooking food or boiling water.

Table 1 Indicators employed in the construction of the potential FSIs
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3.3.2 Disaster resilience capacity and other control variables

Household characteristics, various types of capital, adaptation strategies, and disaster prevention and preparedness are important components when it comes to building household resilience. Hence, we categorize disaster resilience capacity into absorptive capacity (eight disaster resilience attributes), adaptive capacity (seven disaster resilience attributes), and transformative capacities (seven disaster resilience attributes) (Table 2); these three abilities have a linear logical relationship. Firstly, stability is an essential household ability derived from household attributes. Secondly, when a disaster is beyond stability control, flexible adjustments are needed to accommodate the change. Thirdly, transformation is a fundamental change that helps a household cope with future exposure to loss or disasters for an extended time.

Table 2 Indexes of households’ disaster resilience capacity
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In addition to the necessary variables for the composition of resilience capacity, we included several disaster-related variables and households’ basic demographic characteristics. We controlled for the disaster damage experience, which was coded 1 if respondents thought that they suffered losses during the last disaster. However, if they had not experienced a natural disaster in the study area, they stated that they did not suffer losses during the last disaster. We then controlled for the length of residence in the study area. Since the survey sites were disaster-prone, these variables were used to describe the impact of respondents’ experiences with disasters on household food security. Regarding the demographic characteristic variables, we controlled for the age and gender of the respondents. Age is a categorical variable.

3.4 Data processing and entropy method

In this study, potential household food security and resilience capacity are integrated indicators formed by various dimensions of household activities or characteristics. To combine these variables into a comprehensive index and structure the data, we adopted the entropy method. This approach is a relatively objective way to evaluate each index’s weight and each aspect’s comprehensive index; the said strategy is used to describe residents’ resilience capacity and potential household food security in this study. The entropy method is harnessed to determine the index dispersion level. The higher the dispersion of the entropy value, the higher the influence of this indicator in the comprehensive evaluation. Xu et al. (2019) described the entropy method’s specific principle and calculation procedures. Each sub-variable’s sign indicates whether it has a positive or negative effect on the composite index.

Once the entropy method had been implemented, by summing the composite scores of the variables in each dimension, disaster resilience capacity and household food security could be calculated. Among them, ABC, ADC, and TFC indicate households’ absorptive, adaptive, and transformative capacities, which were discrete variables ranging from 0 to 1. Further, FAV, FAC, and FU indicate households’ food availability, accessibility, and utilization, which were discrete variables ranging from 0 to 1. These indicators were used to build the FSI and resilience capacity.

3.5 Method of analysis

This study primarily assesses the correlation between disaster resilience capacity and potential household food security in the pre-disaster stage. The study’s dependent variables are three dimensions of the potential household FSIs, and the independent variables are three dimensions of residents’ disaster resilience capacity. Both groups of variables are transformed using the entropy method. Considering the dependent variables’ discrete characteristics, this study attempted to use the Tobit model. The estimation of the research model was performed via Stata 17.

4 Results

4.1 Potential household food security

Regarding the two food availability aspects, the sample population had good food availability (90%); however, only 54% of the respondents made provisions for drinking water at home. As for the four food accessibility aspects, 96% of the respondents lived near (within 5 km) their food sources. However, the water purification capacity, water purification facility, and tools for acquiring food and water were insufficient, measuring 11%, 29%, and 49%, respectively. Food utilization was composed of four categories. Over half of the sample households had good water and food storage capacity (60% and 52%, respectively). Furthermore, they had a significant safe water identification capacity (74%). Conversely, few populations could identify whether food was safe or not (32%).

The household food security dimensions’ weights were calculated using the entropy method (Table 1). The food availability, accessibility, and utilization scores were then calculated using the entropy method results to show the household food security level for each dimension. Household food security in disaster-prone areas was mainly based on food availability, with the highest comprehensive index (0.592), followed by food utilization (0.471) and food accessibility (0.210; Fig. 3). Each household’s potential FSI was also calculated using the weight from the entropy method results. The FSI ranged from 0 (least food secure) to 3 (most food secure); based on this, the households were divided into six groups. The first group (0 ≤ FSI ≤ 0.5) accounted for 18.7% and the second group (0.5 < FSI ≤ 1) accounted for 18.9% of the households. The third group (1 < FSI ≤ 1.5) accounted for 18.4% of the households, while the fourth group (1.5 < FSI ≤ 2) included the most households (27.5%). The fifth group (2 < FSI ≤ 2.5) consisted of 14.1% of the households. Only 2.4% of the households belonged to the sixth group (2.5 < FSI ≤ 3).

Fig. 3
figure 3

Food security and resilience capacity radar map

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4.2 Disaster resilience capacity

The disaster resilience capacity attributes’ weights were calculated using the entropy method (Table 2). Residents’ disaster resilience in disaster-prone areas was mainly determined by adaptive capacity, which had the highest comprehensive index of 0.520, followed by absorptive capacity (0.403) and transformative capacity (0.315; Fig. 3). Based on the weight calculated using the entropy method, each household’s resilience capacity was measured, which is the sum of absorptive, adaptive, and transformative capacities. Resilience capacity ranges from 0 (least resilient) to 3 (most resilient); based on this, the households were divided into six groups. The first group (0 ≤ resilience capacity ≤ 0.5) accounted for 10% of the households, and the second group (0.5 < resilience capacity ≤ 1) consisted of 28.4% of the households. The third group (1 < resilience capacity ≤ 1.5) accounted for 27.8% of the households. The fourth group (1.5 < resilience capacity ≤ 2) consisted of 21.5% of the households, while the fifth group (2 < resilience capacity ≤ 2.5) consisted of 10.9% of the households. Only 1.3% of the households belonged to the sixth group (2.5 < resilience capacity ≤ 3).

4.3 The relationship between disaster resilience capacity and potential household food security

Table 3 shows the regression results of the three types of disaster resilience capacities and household food security. Model 1, Model 3, and Model 5 represent the correlation between disaster resilience capacity and potential household food security. Meanwhile, Model 2, Model 4, and Model 6 incorporate control variables based on the above models. Overall, the results indicate that the disaster resilience capacity variables have a positive and statistically significant correlation with household food security, but their impacts on the three food security dimensions vary. Firstly, absorptive capacity has a positive and statistically significant correlation with food accessibility. Secondly, adaptive capacity has a positive and statistically significant correlation with all three household food security dimensions. Lastly, transformative capacity has a positive and statistically significant correlation with all three household food security dimensions.

Table 3 Tobit regression results
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4.4 The relationship between other factors and potential household food security

As shown in Table 3, the Model 6 results indicate that the disaster damage experience and age have a negative and statistically significant correlation with food utilization.

5 Discussion

This study focused on the relationship between three disaster resilience capacities and three household food security dimensions against the threats of natural disasters. The results partially support seven of the nine hypotheses proposed and point to two other factors related to household food security.

5.1 Absorptive capacity and potential household food security

Consistent with hypothesis H2a, the results showed that residents with stronger absorptive capacity have better food accessibility. Absorptive capacity represents the stability of the household system and can be adjusted through short-term humanitarian interventions aimed at reducing disaster vulnerability in the short term (Béné et al. 2016). According to our research design, households with high absorptive capacity have greater disaster evacuation mobility and better economic conditions. These attributes, which maintain absorptive capacity, result in a relatively well-maintained living environment (stronger buildings, relatively safe surroundings, proximity to business districts) and well-established household tools. Therefore, the absorptive capacity has a positive correlation with household food accessibility.

Inconsistent with hypothesis H1a and H3a, the results did not show a relationship between absorptive capacity and the other two food security dimensions. The results indicate that a household’s absorptive capacity is limited to influencing its inhabitants’ ability to access food, rather than affecting how much food they can obtain (availability) or how effectively they can utilize these food resources (utilization). The disaster food preparedness of households requires planning for the quantity, variety, and regular replenishment of supplies. This means that households must have flexible disaster management strategies and planning. Achieving efficient food utilization at the household level also requires long-term investment in learning and skill development. As a result, the correlations between absorptive capacity and food availability and utilization are not significant. The result also suggests that establishing a correlation between resilience and a traditional food security index is insufficient to understand how resilience impacts various aspects of household food security. This indicates the need to consider the specific dimensions of the relationship between resilience and household food security when establishing their relationship. Governments can design more efficient measures based on the differential impacts of resilience characteristics to enhance household food security. Lastly, the result also indicates that the impact of short-term resilience attribute on household food security is limited. It is suggested that the government should prioritize training in household disaster management and the development of household disaster preparedness awareness. To complement the limited influence of absorptive capacity, Béné et al. (2016) suggested that households can enhance their adaptive capacity through resilience-building exercises to supplement household absorptive capacity.

5.2 Adaptive capacity and potential household food security

Consistent with H1b, H2b, and H3b, the results showed a positive relationship between adaptive capacity and all three household food security dimensions. Adaptive capacity measures “the ability to make informed choices about alternative livelihood strategies based on changing conditions” (Béné et al. 2012). Adaptive capacity consists of a set of disaster prevention strategies adopted by a household, indicating a household’s strong adaptability and flexible adjustment. Existing research has proved that the implementation of these strategies and behaviors is driven by strong disaster perceptions (Kurata et al. 2022; Ong et al. 2023). The development of disaster perception is influenced by various stressors, such as norms, culture, the availability of and access to information, the value placed on that information, and the immediate social circle (Béné et al. 2019; Jones and Boyd 2011). In this study, similarly, the diversity and flexibility of adaptive strategies stem from households’ high-risk perception. Such perceptions lead households to take further steps in terms of protective behaviors to ensure household well-being, which is closely related to food security. Under this protective behavior, the focus is on learning about food security in times of disaster and how to handle and purify food or how to store it and protect it from being damaged. Thus, the combined evidence explains how higher adaptive capacity improves all three household food security dimensions. The study illustrates the effectiveness of incremental adjustments in disaster preparedness management by households to improve food security in all aspects and emphasizes that the Japanese government should continue current disaster management policies to promote bosai ishiki (disaster prevention awareness) among residents. This is due to the fact that, in Japan, bosai ishiki (disaster prevention awareness) is recognized as the main way to promote self-help and mutual assistance among residents (Cabinet Office, Government of Japan 2023). It also proves that this initiative can promote disaster food security in Japanese households.

5.3 Transformative capacity and potential household food security

Consistent with H1c, H2c and H3c, the results showed that households with stronger transformative capacity have better food availability, food accessibility, and utilization. Transformative capacity represents a fundamental change in the household system, which helps the family system cope with severe shocks in the future. However, there are numerous barriers to this fundamental change, all of which are rooted in cultures and cognitions. Hence, it is necessary to acquire and accumulate new knowledge and then utilize this in a different area. Previous studies have identified that education, learning from previous disasters, and drills could improve long-term disaster management capacity (Ardalan et al. 2020; Yin et al. 2021). In Japan, the Disaster Risk Reduction Drill Plan and Japan disaster management pamphlet have been used to inform people of the necessary disaster preparedness materials and how to utilize them well. Moreover, social engagement and decision pluralism could help households learn more about disaster management mechanisms within the community and strengthen the ties between them and the community. Residents participate in activities organized by Chonaikai and Jichikai, such as disaster prevention drills. These activities are based on local conditions, significantly enhancing residents’ sense of participation and community responsibility, thereby fostering a spontaneous and transformative shift in their perception of household disaster management. Moreover, women’s participation and voice are important for effective disaster management in Japanese households, as women are responsible for most of the household activities and disaster preparedness tasks. They are more experienced in using household storage facilities and handling food, while they also have more disaster management knowledge (Petraroli and Baars 2022). Therefore, establishing tight information connections between households and communities, as well as ensuring equal participation of household members in disaster management affairs, can cultivate a positive and long-term sustainable disaster management environment within the household, and such an environment motivates families to learn more about their food availability, food accessibility, and utilization.

5.4 Other factors and potential household food security

The results indicated that age negatively impacts household food utilization. Japan has a rapidly aging population and the well-being of and support for elderly and senior people after a disaster are critical to disaster recovery. Elderly and senior people are ill-prepared for and have a low-risk perception of disasters, which can increase the risk of food-borne illness in times of disaster (Kosa et al. 2012). Particularly, many elderly and senior adults lack knowledge of safe food and do not follow safe food recommendations (i.e., they might not be able to identify unsafe foods or have specific food storage areas) (Cates et al. 2009). In this study, 26.5% of the respondents were over 60 years of age, and the results indicated that their food utilization is lower than that of the younger respondents. This might significantly expose them to secondary damage after a disaster. Therefore, the government should promote activities to enhance the efficient use of food by elderly and senior people.

Previous studies have reported that disaster-related experiences promote households’ food stockpiling preparedness and enhance their knowledge of disaster risk management. However, our study showed that disaster damage experiences negatively influence food utilization. This might be explained by the psychological effects of disasters. Natural disasters often have a strong relationship with mental health, as unpredictability and huge losses can severely undermine victims’ mental health. Psychological trauma can lead to victims denying losses and trying to escape from reality (Makwana 2019). In the study area, residents have been exposed to two mega natural disasters in the last decade, namely the 2016 Kumamoto Earthquake and the July 2020 heavy rains. These multiple exposures may have produced more stress and trauma, affecting people’s mental health (Shultz et al. 2013). Such stress might prevent residents from accumulating disaster management-related knowledge, such as how to process drinking water and store food.

Despite its contributions, this study has some limitations. The characteristics of those households with lower food security and resilience levels were not clearly defined. Since these vulnerable groups tend to be most affected by disasters, future research should further analyze the household characteristics of these groups via the use of cluster analysis.

6 Conclusions

This study explored the relationship between disaster resilience and potential household food security. As climate change continues to worsen and natural disasters increase in frequency, this study could be instrumental in informing disaster risk reduction policies related to household food security. Based on data from a disaster-prone area in Japan, the following conclusions were drawn.

  1. 1.

    Over half of the residents had low potential FSIs. This means that, in Japan, household food security is not guaranteed if humanitarian aid does not arrive in time after a disaster. Particularly, food accessibility is relatively weak, as water reserves, purification, and processing capacity are lacking. Thus, when encountering a water cut or contamination, households will face water shortages. We suggest that public administrators should make more efforts to systematically educate the population regarding potential food security threats to households during disasters and pre-disaster food security preparations. This would allow residents to understand the importance of food security in times of disaster and raise the potential household food security level.

  2. 2.

    Residents’ average disaster resilience score is low, and when a disaster strikes, they might suffer a huge shock and find it difficult to recover. Specifically, they have a relatively low transformative capacity, which reflects their limited understanding and awareness of future disasters. This requires public administrators to target the appropriate basic resilience constituent elements and provide residents with enhanced measures to strengthen household food security. Such measures include focusing more on vulnerable populations’ well-being, training in disaster response strategies, and increasing awareness to transform disaster preparedness knowledge from a short-term action into a long-term habit.

  3. 3.

    Three types of disaster resilience capacities partially and positively impact the different household food security dimensions. This suggests that enhancing disaster resilience at the household level could positively impact potential household food security and reduce the harm caused by the food security crisis after a disaster. Governments can design more efficient measures based on the differential impacts of resilience characteristics to enhance household food security.

  4. 4.

    We also note that the disaster damage experiences negatively influence food utilization. This implies that disasters cause psychological trauma for individuals. Governments should prioritize organizing psychological counseling in disaster-prone areas to promote mental well-being.

  5. 5.

    Lastly, we found that households’ ability to utilize food decreases with age, indicating a lower disaster resilience among elder generations. Japan has an abundant aging population, and food-borne illnesses might seriously impair the post-disaster recovery of elderly and senior people owing to physical reasons and a lack of understanding when it comes to the hazards of disasters. Hence, it would be better to promote education and the adoption of suitable food safety practices among elderly and senior populations. For example, disaster preparedness materials should be tailored to elderly and senior people and more details regarding food security risk during disasters ought to be provided.