Food and health security impact of climate change in Bangladesh: a review

Bangladesh is one of the most densely populated countries in the world, having a total population of about 160 million. As 80% of the country is made up of low-lying floodplains, Bangladesh's rural areas are its main economic sectors. However, the country is rapidly urbanizing, and its agricultural manufacturing, transportation, trade, and other economic activities are growing. Climate change has a greater risk for Bangladesh (Agrawala et al. 2003), and there have been around 290 deaths per 1,000 people, including both fatalities and injuries (Nelson 2003). The world has been experiencing climate change, which has led to extreme drought in Asia and Africa as well as heat waves in Bangladesh, India, China, and the UK. Because of climate change, the global climate temperature has been increasing, which gets warmer due to the greenhouse gas (GHG) emissions resulting from human activities. So, Bangladesh is considered as one of the most vulnerable countries in the world (BBC 2006; Maplecroft 2014). Additionally, at least 150,000 people worldwide pass away each year because of climate change. In recent years, Bangladesh has achieved notable strides in decreasing poverty, raising food production, and improving health outcomes. Despite this, the nation continues to confront significant issues with regard to food and health security, particularly in light of the COVID-19 epidemic, natural catastrophes, and climate change. Approximately 25 million people in Bangladesh are food insecure, with approximately 11 million of them experiencing acute hunger as a result of the pandemic and other circumstances, according to a recent study by the World Food Programme (WFP 2021). The impact of COVID-19 on health and nutrition is also highlighted in the study, with supply chains disrupted, access to health care decreased, and rates of malnutrition among children and expectant women rising. Similar findings were made by the Bangladesh Bureau of Statistics (BBS), which discovered that the pandemic had reduced household income and food consumption, with low-income families being severely impacted (BBS 2021). Children and elderly people are the most disadvantaged communities in the world. So, this has a severe health impact. Malnutrition and infectious illnesses are important concerns for vulnerable groups including women and children, and these issues have broad consequences for health. Climate change has been changing and it has direct and indirect effects. Government policy-making bodies need to be made aware of these effects. Globally, both direct and indirect effects of climate change and fluctuation are causing psychological health difficulties (Speldewinde et al. 2009; Berry et al. 2011). According to Swim et al. (2009), marginalized populations, communities that depend most heavily on the local ecosystems, and areas with a history of mental illness or other issues are all expected to experience widespread, cumulative, and severe psychological health effects from climate change (Swim et al. 2011). The majority of the study to date has come from Australia, Canada, and the USA, with very little research being done in Bangladesh (Berry et al. 2011). The strength and availability of social support networks, economic stability, cultural practices, physical health, kinship ties, previous historical events, access to psychological health resources, the ability to engage in fishing, hunting, trapping, foraging, and traveling for sustenance and livelihoods, the availability of housing, the quality of early life, access to education, and sense of belonging are all factors that influence psychological health (Kirmayer et al. 2009). One of the most significant new threats to humanity's psychological well-being is climate change. The effects of climate change on the psychological health of those suffering have been the subject of numerous studies (Green 2006; Berry et al. 2010). Malnutrition, food and waterborne illnesses, infectious diseases, and increased air pollution are all caused by climate change (Patz et al. 2005).

Heat waves and floods, which are brought on by greater temperatures, excessive rainfall, and the thermal expansion of the oceans, are the primary causes of injury and illness. GHG emissions are one of the factors responsible for creating food security and human security (Lake et al. 2012). Lobell et al. (2011) have given a good account of the effects of climate change on food security, defined as having access to sufficient, safe, nutritious food to maintain a healthy and active life (WHO 2014). Additionally, climate change has been considered an important factor that can cause the occurrence of food safety hazards in enormous stages from primary production to consumption (Tirado et al. 2010). Many researchers have found a greater global health impact and increasingly recognized as a public health priority which is occurring because of climate change in the 21st century (Young et al. 2002; WHO 2008; Yongyut et al. 2009). Bangladesh is prone to cyclones, earthquakes, floods, and other natural calamities (ICDDRB 2011). The identification of the connections between Bangladesh's food systems, climate change, and health is one of the significant contributions of contemporary study. According to studies, climate change increases food poverty, water shortages, and decreased agricultural output. The significance of an integrated strategy for tackling food and health security in Bangladesh has also been underlined by recent research. This strategy acknowledges the connection of food systems, health, and climate change and aims to tackle these problems in a coordinated and all-encompassing manner. The Bangladesh Climate-Smart Agriculture Investment Plan, for instance, is a project that strives to promote sustainable and climate-resilient agriculture while highlighting the need for diversification, adaptation, and innovation (Siddique et al. 2022). These findings highlight the need for ongoing initiatives to enhance food and health security in Bangladesh, including increasing financial commitments to the country's agricultural sector, social safety net, and hospital infrastructure. There are still a number of research gaps that need to be filled despite the expanding amount of literature on Bangladesh's food and health security and the effects of climate change. First, more study is required to comprehend the socioeconomic and cultural elements that influence how vulnerable certain communities are to climate change. Second, further study is required to determine how non-communicable diseases like diabetes, hypertension, and cardiovascular conditions, which are on the rise in Bangladesh, may be impacted by climate change. Third, additional study is required to understand how gender affects climate change adaptation plans, particularly in terms of food and health security (Pierce et al. 2020). The main goal of this literature review is to investigate how climate change would affect Bangladesh's food and health security in light of the aforementioned knowledge gap. The goal of the paper is to present a thorough examination of the current body of information on this subject and to pinpoint areas that still require more study. The evaluation also aims to give suggestions for researchers and policymakers on how to deal with the problems Bangladeshi food and health security is facing as a result of climate change. Peer-reviewed studies, government reports, and other pertinent data sources, among others, are analyzed as part of the review research (Islam et al. 2020). Food security, health security, the effects of climate change on agriculture and fisheries, adaptation and mitigation strategies, and policy implications are only a few of the many themes covered in the review.

A number of factors, such as extensive agricultural land degradation, soil erosion, river erosion, a loss in soil fertility, water logging, acidification, and deforestation, among others, have a significant impact on agricultural production and food supplies or food security. Agriculture is a key economic sector in Bangladesh. A storm, a drought, or a flood are only a few examples of the climatic pressures that are putting strain on it. Other non-climatic stresses include population expansion and increasing urbanization. For instance, the nation loses 2% of its GDP annually as a result of climatic extremes, and it is anticipated that this loss will increase to 17% by 2050 (The Daily Star 2021). Islam et al. (2022) used the vector autoregression (VAR) model to analyze data between 1984 and 2017 to assess the association between food loss and national food security in Bangladesh with regard to climate change and extreme climatic occurrences. They discovered that food security is significantly harmed by food loss. According to research on ‘poverty and natural disasters’, Karim & Noy (2016) suggest heterogeneous household effects resulting from natural disasters, focusing on the fall in consumption and household per capita income. The household food security and consumption in Northern Kenya, as well as other rural livelihoods, are negatively impacted by drought and other extreme weather occurrences (Maione 2020). According to research on tropical storms' severe occurrences and household food consumption, hurricane losses and damage resulted in a 1.1% decrease in per capita food consumption. Affected households were pushed to spend more on food consumption and divert money from non-food expenses (Henry et al. 2019). Thomas et al. (2010) and Arouri et al. (2015) show that extreme climatic events like storms significantly reduce family consumption levels by 1.5% in Vietnam using cross-sectional and panel data. Anttila-Hughes & Hsiang (2012) highlighted the fact that devastating typhoons caused a drop in household food consumption in the Philippines from 5.9 to 7.1% (Table 1).

Food security has been significantly impacted by climate change, which has increased the frequency and intensity of climatic disasters such as floods, droughts, and cyclones (Ali et al. 2020; Faisal & Parveen 2004). According to recent studies, Bangladesh's shifting climate and extreme weather patterns have a substantial impact on crops, especially rice production, which is a staple grain for the nation. The southern coastal belt and Bangladesh's northern area are particularly hard hit (Sarwar & Khan 2007). Food supply and accessibility are impacted by decreasing crop yields brought on by floods and saltwater intrusion into fields. According to a 2017 assessment by the Bangladeshi government, agricultural yields have decreased 7–10% as a result of climate change, costing farmers significantly more money (Government of Bangladesh 2017). Climate change is not just reducing agricultural yields in Bangladesh; it is also having an impact on food safety and quality. Pest and disease outbreaks are increasing as a result of warming temperatures and shifting precipitation patterns, which poses a threat to food safety and lowers crop quality. Extreme weather conditions can also deteriorate the infrastructure for food delivery and storage, causing food to decay and go to waste. All of these elements contribute to Bangladesh's rising food security dilemma, which is expected to get worse as climate change gets worse (Islam 2008). Bangladesh is among the nations that are most negatively impacted by climate change, according to the Climate Risk Index (2021). Due to the regular occurrence of extreme weather conditions such as cyclones, floods, droughts, and heat waves, it is vulnerable to climate change. The nation's food security has been negatively impacted by these incidents (Climate Risk Index 2021). According to a 2019 report by the International Food Policy Research Institute, Bangladesh's rice output might decrease by 10% by 2050 compared to a scenario without climate change due to variables associated with climate change. The study predicted that by 2050, heat stress, floods, and other climate change-related catastrophes might decrease the nation's output of wheat by 30%, maize by 14%, and potatoes by 6%. In a subsequent assessment released in 2020, the United Nations Development Programme (UNDP) noted that Bangladesh's food systems have been significantly impacted by climate change, which has resulted in food poverty and malnutrition (Bloem et al. 2009). According to the research, food insecurity and malnutrition would grow nationwide due to climate change, with the poorest and most vulnerable populations suffering the most (UNDP 2020). Climate change has had a huge influence on Bangladesh's fishing industry as well. According to 2018 research, climate change might significantly reduce the nation's fish supply, which would have an impact on the livelihoods of millions of people who depend on fisheries (FAO 2018). Fish breeding and survival are impacted by sea level rise and water temperature changes, which lowers fish productivity (Siddique et al. 2022). In conclusion, Bangladesh is suffering greatly from the effects of climate change, which are only becoming worse. To create resilience in the nation's food systems and to adapt to the changing environment, immediate action is needed.

The influence of climate change on Bangladesh's food and health security is a complex issue beset by several difficulties. The biggest obstacle to adaptation is a lack of institutional and financial resources. The majority of people are smallholder farmers, who have limited access to financing and insurance to make investments in climate-smart activities. Another major obstacle is inadequate infrastructure, such as inadequate irrigation, drainage, and water management systems (Ahmed et al. 2020). Farmers frequently rely on climate-sensitive agricultural techniques like monoculture due to a lack of institutional capacity and financial resources, which poses serious concerns to food security and environmental sustainability (Haider et al. 2018). Societal obstacles including gender inequity, limited access to education, and a lack of knowledge about climate-smart activities are among the other difficulties (Woodward et al. 1998). The nation's food and health security are suffering because of these implications. While there have been some attempts to address these issues through adaptation strategies, there have been glaring gaps in imagination and innovation when it comes to addressing the changing effects of climate change on Bangladesh's food and health security. The creation of sustainable and climate-resilient agriculture techniques is one area where innovation has been lacking. Although there have been some initiatives to encourage sustainable farming methods, such as crop diversification and soil preservation, these actions have not been scaled up or generally embraced. For instance, according to a 2018 assessment by the International Fund for Agricultural Development (IFAD), only around 20% of Bangladeshi farmers were employing climate-resilient farming practices. This shows that in order to enhance food security for rural areas and increase resilience to the effects of climate change, Bangladesh has to innovate and invest more in sustainable agriculture.

First, there might not be enough technical or financial resources to help smallholder farmers make the shift to climate-resilient methods. Secondly, even though research and development initiatives are essential, Bangladesh may not have the resources or the expertise to do studies on climate change and its effects on the country's food and health security. Last but not least, there can be sociocultural obstacles to successful climate change adaptation, such as ingrained gender norms or conventional beliefs, which cannot be resolved exclusively through technological measures.

In Bangladesh, a few programs and actions have been implemented to address the effects of climate change on food and health security. To support sustainable development, the government has presented the Bangladesh Climate Change Strategy and Action Plan, which is described in its Nationally Determined Contributions under the Paris Agreement. In order to boost agricultural output and foster resilience among populations impacted by climate change, the government and non-governmental organizations (NGOs) have increased the adoption of climate-resilient strategies, technologies, and practices (Schmidhuber & Tubiello 2007; Kabir et al. 2019). These include promoting agricultural variety, agroforestry, crop intensification, and a decrease in the use of chemical fertilizers in agriculture. According to the report, it is advised that a coordinated effort be made to solve the issues with Bangladesh's food and health security caused by climate change. This entails collaboration between the government, NGOs, farmers, and other stakeholders to develop a policy environment that prioritizes spending on infrastructure that is climate-resilient and providing financial assistance to smallholder farmers. In addition, encouraging sustainable agricultural methods including crop diversification, crop intensification, and agroforestry can aid in boosting climate change resistance. In order to effectively adapt to climate change, it is also necessary to address sociocultural impediments and strengthen institutional capacity. Additionally, efforts in research and development have to concentrate on locating crop kinds and farming techniques that are climate-resilient and appropriate for Bangladesh's regional situations.

All authors included a review of the literature, reports analysis for making comparisons, and created figures based on the previous and current data write-up of the manuscript.

All relevant data are included in the paper or its Supplementary Information.

The authors declare there is no conflict.