The Goal-2 of Sustainable Development Goals (SDGs), ‘Zero Hunger’, sets the member states of United Nations on a path of achieving food security and eradicate malnutrition for their citizens by 2030 [1]. Malnutrition refers to the deficiencies, excesses, or imbalances in an individual’s consumption of nutrient-dense diets [2]. According to World Health Organization (2020), one-third of low- and lower-middle income countries currently experiences extreme malnutrition, particularly in Africa, the Pacific, and the South and East Asia. Many people are being exposed to under-nutrition because of food shortage and obesity due to changing eating habits. As such, about 30 percent people of all ages are undernourished and 20 percent are overweight in low- and lower-middle income countries [3]. To eliminate malnutrition in these countries, there is an importance to understand: who are the malnourished; where they are located; and why they are malnourished.
The people aged 50 years and over are generally inclined to malnutrition because of their physiological, psychological and functional changes that occur with aging [4]. As noted earlier, this prevalence is high in low- and lower-middle income countries that results in negative health effects at old age, such as reduced immunity, physical and intellectual disability, and compromised productivity [5]. According to Spencer et al. (2012) and Vafaei et al. (2013), the physical and psychological health problems including anemia, poor memory, weak immune system, infections, muscle weakness, tiredness, unintentional weight loss, depression and anxiety are closely related to malnutrition and common in older adults [6, 7]. Malnutrition also increases their risk of comorbid and chronic conditions, for instance, overweight and obesity are major causes of type-II diabetes, respiratory and cardiovascular diseases, various cancers and multiple organ failure [8]. Such morbidity and comorbidity patterns among the adults inform a stipulation of community-based investigation of malnutrition risks in low- and lower-middle income countries including Bangladesh.
Our paper focuses on Bangladeshi wetland community-dwelling older adults’ [≥ 50 years – referred as older adults in this paper] malnutrition risks and their associated factors. Bangladesh, a lower-middle income country, has been identified as having one of the largest river deltas in the world. Total area of the country’s wetlands [generally referred as rivers and streams, freshwater lakes, marshes, haors, baors, and beels] is estimated to be eight million hectares [9]. The major wetlands of the country include Hakaluki haor, Chalan beel, Atrai basin, Punarbhaba floodplain, Gopalganj-Khulna Beels, Arial Beel, and Surma-Kushiyara floodplain [10]. The country has been experiencing a rapid growth in the number of people aged 50 years and over and the proportion of these people is 16 percent of the country’s total population [11]. About 73 percent of the adults live in rural areas and of them, 30 percent live in wetland villages [12]. Literature reports that women of reproductive age and children live in wetland villages are susceptible to malnutrition because of natural hazards, health illiteracy and food insecurity, while nutrition-related data for the people aged 50 years and over is not well-documented [11, 12]. Therefore, we aim to: (a) review the literature to contextualize ageing trends, nutritional aspects and wetland communities in Bangladesh; and (b) conduct a cross-sectional research to determine the prevalence of malnutrition, malnutrition risks and the factors associated with malnutrition of wetland aging.
Literature Review: Ageing, nutritional aspects, and wetland communities in Bangladesh
Bangladesh has the third largest population of poor older adults in the world [13]. Older adults accounted for five percent of the total population of Bangladesh in 1991 and nine percent in 2015, and it has been projected that one in every five persons will be classified as elderly in 2050 [14, 15]. It is also expected that this proportion of older adults will be equal to the proportion of young people in the second quarter of the 21st century [13]. This ageing pattern has become a major challenge in Bangladesh due to a steady increase in the size of the older population with poor living conditions and scarce resources, especially in the wetland communities.
Malnutrition rate is the highest in Bangladesh among the world and almost one-third were suffering from malnutrition. Many people in Bangladesh eat less or eat energy-dense food of low nutrition value as they get older and they are at risk of malnutrition and related health problems. The primary malnutrition of the older adults is caused by a lack of energy (fats and carbohydrates), protein and micronutrients (vitamins and minerals) in the diets of infants and children and the secondary malnutrition is caused by the lack of one or more nutrients in adult diets, ranging from energy deficiency in anorexics to vitamin deficiencies in older people with poor appetite [16]. This risk is high among the older adults, especially in the country’s wetland communities, because they are deprived of basic humanitarian needs and live under extreme poverty.
About one-third of the Bangladeshi older adults live in wetland villages. Evidence shows that wetlands provide many benefits for people, for example, fisheries and agriculture are the two major livelihoods for the wetland people and there is an access to high nutrient and fiber foods [17–19]. But these villages are perceived as the place of undernourished or malnourished because the food consumption process remains unhealthy due to a lack of health consciousness [20]. The general education rate is low and heath illiteracy is high in the wetland villages and this factor together with an inadequate nutritional programs and services may impact significantly on their malnutrition [20–23]. According to literature, the older adults in wetland communities are vulnerable than main land population and other wetland community groups to malnutrition for many reasons including hunger and low food intake, physio-psychosocial and functional changes that occur with age, and inadequate access to food [24, 25]. Their problem is compounded by poor nutrition together with physical illness, including both communicable and non-communicable diseases.
In Bangladesh, the ageing and nutrition aspects in wetland communities are often neglected in policy documents and in the literature since most of the dietary intervention programs organized by government’s community clinics are directed toward infants, young children, adolescents, and pregnant mothers [26]. Little is known about the malnutrition status of wetland community-dwelling older adults and how the physio-psychosocial and living circumstances place them at risk of malnutrition. This review and cross-sectional study will help to answer all these questions.