To the best of our knowledge, this study is one of the first to provide evidence regarding the nationwide prevalence and factors associated with being underweight among 15- 49-year-old women of reproductive age in Sierra Leone (Table 1, Table 2, Fig. 1). To ensure optimum generalizability of our findings, we used nationally representative data from the Sierra Leone Demographic Health Survey of 2019 (19-SLDHS) [30]. Specifically, this study has precisely determined the prevalence of underweight among women of reproductive age in Sierra Leone at 6.7% (502/7,514) (Table 1). It revealed that age group, residency in the northern region of Sierra Leone, not listening to radios, and marital status (unmarried) were significantly unlikely to have underweight (Table 3). Furthermore, the study found parity, residency (rural versus urban), sex of the household head, household size, work status, level of education, wealth index, reading magazines, smoking cigarettes, and Alcohol use as not significant covariates of underweight (Table 2).
We expect this study to provide policymakers with evidence regarding underweight among women in the reproductive age of 15–49 years in Sierra Leone. The prevalence of underweight at 6.7% (502/7,514) is within a range comparable to many countries in sub-Saharan Africa [38, 39, 40, 41]. The prevalence of underweight was lower compared to studies conducted in Kenya (9%) [38] and Tanzania (10%) [39] but like that in Nigeria (6.7%) [40]. This prevalence is also within the range of 5 to 20% reported for African women [40]. The observed differences in the underweight prevalence in Kenya, Nigeria, and Tanzania could be due to differences in characteristics of study participants, such as age and their food security status. In the study conducted in Nigeria by Senbanjo et al., only women aged 15–39 years from one state in Lagos were included in the survey, while the other two studies from Tanzania and Kenya included women aged 15–49 years like our study that included women aged 15–49 years [40]. In addition, Uganda has the lowest food insecurity in the East African region, which could explain the lower underweight prevalence in Uganda compared to Tanzania and Kenya [41]. Compared with Asian countries, this prevalence rate in Sierra Leone is lower compared to Indonesia at 11.2% and another Asian country, Bangladesh, at 30.4% [42]. Therefore, the observed differences in the prevalence of underweight among women of the reproductive age (15–49 years) in the five countries mentioned above could be due to differences in characteristics of study participants, such as the country of origin and their food security status.
The least likely odds of being underweight among respondents aged 25–34 years was AOR = 1.670,95%CI:1.254–2.224; p < 0.001 and 1.6 times lower than those aged 15–24. This finding contrasts with other studies [43, 44, 45]. This finding could be because this age group (15–24 years) consists mainly of adolescents in a period of rapid physical growth, psychosocial, and cognitive development, posing an increased need for nutrients which may not be sufficient in the situation of Sierra Leone [46]. In addition, over 50% of adolescent girls in South Asia are affected by undernutrition and anemia [47]. Likewise, undernutrition is high among adolescents living in sub-Saharan Africa, including Ethiopia [48, 49]. This report may be due to poverty and lack of enough food available for consumption because dietary habit is one of the main factors for underweight in adolescents [50, 51, 52].
Our study found that most participants, 3,571(47.5%), received no formal education (Table 1 and Table 2). As most of the participants hailed from rural areas 4,422(58.9%), it was impossible to ascertain if the proportion of people with no formal education was comparatively lower among the urban population (Table 1). However, it was probable that there has been an under-ascertainment, as the actual proportion of people with no formal education could be slightly higher in urban settings than what is reported (Table 1). Because most participants in this survey were women aged 20–29 years, 2,528(33.6%) and this age group were likely to have a higher proportion of formally educated people compared to their older counterparts (Table 1). Consequently, it could slightly inflate the overall prevalence of people with no formal education in the older age group categories (Table 1).
Interestingly, our study found that Sierra Leone women who were married in the survey had 59.4% higher odds of being underweight (Table 2). Contrary to our findings, a previous study in the context of Bangladesh, through a pooled analysis, found that not being married was positively associated with being underweight [53]. Two previous studies in Ethiopia and Iran too contrasted our findings [54, 55].
In many developing countries, being married provides women with more excellent financial stability, which in turn works as a protective factor from being underweight [56, 57]. Other factors, such as using contraceptive pills, and weight gain in the postpartum phase, are more likely to be prevalent among married women in many countries’ contexts [56, 57]. One study in Ethiopia showed that women's nutritional status is affected by lactation, family planning method utilization, lack of education, illness, and poor dietary habits [58]. However, our study excluded pregnant, post-natal, and postpartum women, perhaps explaining the findings among this study participants. Although the hypothesis that married women get protected from being underweight because of a social shield, it must be explained in terms of the country's specific context. There is a need for a proper and factual explanation of the plausible hypothesis of social protection for married women and therefore warrants a deeper exploration of the socio-cultural dynamics of Sierra Leone because the current findings were contrary to what was seen in Ethiopia and Iran [54, 55]. As expected, further studies will be necessary to establish or refute any plausible causal connections between being unmarried and having lower odds of being underweight, as observed in Sierra Leone.
Our finding shows that women who belonged to the Eastern, Northwestern, and Southern regions of Sierra Leone were more likely to be underweight compared to women in the Northern region (Table 2). Region of residence is associated with undernutrition in similar low-income African settings [59, 60, 61] and Afghanistan [62]. A similar study in Uganda found that the Northeastern region of Uganda was the most food in secured and the poorest [63]. This finding could be because the Northeastern Uganda region has prolonged annual droughts and experienced long civil unrest, significantly affecting their agricultural production and economy compared to the other regions that have been stable without civil conflicts [64]. In addition, the decreased agricultural production and poor economy due to the prolonged drought and civil war-induced food insecurity are typical [65]. Reduction of own food production and decreased food availability and access to the population is typical [65]. This situation leads to inadequate food in both quality and quantity, risking them being underweight.
Additionally, most people in the Northeastern region of Uganda, unlike the other regions, are pastoral communities (some are nomadic), and this may negatively affect their consumption of foods of agricultural origin (crops) as they mainly focus on pastoral activities [65]. Furthermore, pastoralism increases the risk of being underweight in Ethiopian pastoral communities [59].
The case in the Eastern, Northwestern, and Southern parts of Sierra Leone is more likely to have underweight women because of its post-conflict attributes of high youth unemployment, corruption, and weak governance [66]. In addition, a recent Sierra Leone report shows that nearly half a million children under five suffer from stunting, while 30,000 suffer from malnutrition and are at immediate risk of death due to inadequate dietary intake and the high disease burden affecting young children [66]. Experts believe four primary factors contribute to Sierra Leone's overwhelming poverty: government corruption, an established education system, absence of civil rights, and poor infrastructure [66]. These factors make poverty challenging to beat, and researchers should not overlook the uniqueness of the characteristics of the population in Northern Sierra Leone. The cultures, the tribes, the dominant religious practices, marital arrangements, and the social dynamics of the population in the northern region of Sierra Leone could explain the low likelihood of being underweight among their women [66].
Listening to radios: A study in Botswana found that approximately 12.9% of women who did not listen to radio the previous week compared to 11.1% who did, had a low BMI or were underweight. Overall, a higher proportion of women who never listened to the radio at least once a week had a high prevalence of under-nutrition [67]. This finding contrasts with our current study in Sierra Leone, where not listening to radios was unlikely to be associated with being underweight (Table 2). In addition to the above common factors, young adult women who lacked access to mass media were at a greater risk for under-nutrition in Botswana [67].
Radio is a crucial source of information on various issues such as health communication and promotion [67]. Through radios, people receive and learn messages about healthy eating behaviors and lifestyles [67]. As such, those who own radios are expected to be better informed and therefore be able to adopt a healthier lifestyle [67]. The assumption in that study was that participants without a radio did not know about healthy eating behaviors and lifestyle and therefore were more likely to be underweight [67].
Our study finding presents the contrary since those who did not listen to radios had an unlikelihood of being underweight (Table 2). We posit that the culture, religious practices, feeding habits, and economic activities of women in the northern region of Sierra Leone may be different from that of Botswana, Uganda, and Ethiopia, where radio listening is associated with less likelihood of women being underweight. Most significantly, information coming from the northern part of Sierra Leone shows that the women are more involved in petty trade and sedentary life. The population was Muslims, and food was readily available for the women in the northern region. Therefore, not listening to the radio would not affect the nutritional intake of the women in that northern region of Sierra Leone.
Strengths and limitations of the study: This study has several notable strengths. First, this study utilized a nationally representative sample population. The data quality is assured as the SLDHS uses well-trained field personnel, standardized protocols, and validated tools in the data collection processes. As a result, the findings of the study can be generalizable to the target population of Sierra Leone. Second, due to the utilization of validated tools and calibrated instruments by SLDHS, the generated estimates are more robust than any other study in the Sierra Leone context. In addition, we used data with a large sample size collected, entered, and cleaned by a team of trained and highly experienced scientists, limiting mistakes in the data set. Finally, as we used the concentration index, the findings are more robust in predicting socio-economic inequalities.
However, the limitations of the study warrant discussion. First, the 2019 SLDHS was a cross-sectional survey. As a result, we cannot establish a temporal relationship between the explanatory variables and the outcome variable. Second, due to the absence of data, several significant variables, such as food security and dietary diversity, could not be included in the final model for the analysis. Third, SLDHS did not collect individual household incomes and expenditures data. It used the wealth index as a proxy indicator for its measures. Fourth, SLDHS collected data on 15–49 years older women of reproductive age. With the current changes in adolescents' actions and behaviors, aren’t there children less than 15 years who have gone through the cycle of reproduction? As a result, the distribution of undernutrition and overnutrition could not be obtained for women below and beyond this age group (15–49 years). Finally, most data on the predictors were based on self-reported information and were not verified through records which risks socially acceptable answers hence social desirability bias.
Generalizability of the results: Results from this study can be generalized to low resource settings in low- and middle-income countries.