The NutriShed Framework
The "Nutrished" framework (
Figure 2) focuses on tracking spatially explicit nutrient flows into and out of study communities. Sequentially, it: (i) assesses the nutritional needs and priorities within the study communities, (ii) determines regional gaps in production, food markets, and infrastructure, (iii) identifies vulnerabilities in critical nutrient flows, and (iv) employs empirical spatial tools and systems modelling to devise strategies for enhancing nutrition security. The key stages of this approach are described in detail, below.
Stage 1: Identifying the Nutrient gaps
The NutriShed assessment framework begins with a nutrient gap analysis. We identified specific nutrient deficiencies and nutrition priorities across the study locations. We conducted a household-level dietary assessment survey including nutritionally vulnerable groups (women, children, and adolescents) in the two study communities. The dietary analysis enabled identification of the limiting nutrients in the diets of respondents. The women were aged 18 years or older and were selected because of their role in household food purchase, and cooking decisions; adolescents between ages 12 to 18 years, and children aged 2 to 5 years from selected households. Only one eligible woman, adolescent, or child was recruited per household for the dietary assessment.
For the dietary assessment survey, we adapted the interactive 24-hour recall method by Gibson and Ferguson (2008), administered using computer-assisted personal interviewing. A multiple-pass approach was employed in conducting the dietary recall interviews. In the first pass, the respondent listed all the foods and drinks (including drinking water) consumed during the preceding 24-hour period. In the second pass, the interviewer guided the respondent through each food item listed, in chronological order, probing for more detailed descriptions, including cooking methods and, where relevant, brand names. The third pass involved estimating portion sizes for the reported foods and drinks. In the fourth and final pass, the interviewer reviewed the recall to ensure that all items were accurately recorded. The types and quantities of food consumed were estimated using household measures, food models, volumetric cups, measuring spoons, and a photographic food atlas with weights.
Following the 24-hour dietary recall, a nutrient gap analysis was conducted by analyzing the dietary intake reported by participants. At the initial stage of analysis, dietary intake data were translated into nutrients and energy using a combination of the Food Recognition Assistance and Nudging Insight (FRANI) food database, the Research to Improve Infant Nutrition and Growth (RIING) food database, and a compilation of nutrients from the West Africa Food composition database. These databases contain nutrient data on indigenous foods typically consumed in Ghana. These food databases include nutrient content data for macro- and micro-nutrients like energy, carbohydrate, protein, fat, fibre, calcium, zinc, vitamin A, thiamin, riboflavin, niacin, vitamin B6, vitamin B12, folate, iron, pantothenic acid and vitamin C. Food ingredients used in preparing each meal were equated to the closest food code in the RIING database. The consumed quantities (portion sizes) captured in grams were then entered into the RIING database and the code that is the most accurate description of each reported meal was selected in the database. This selection automatically produces nutrient and energy values commensurate with each consumed portion size using MS Excel. This was followed by further analysis using the STATA statistical software (version 17). The estimated average requirement for each nutrient, appropriate for the respective age group and gender, was compared against the respondents' intake to evaluate adequacy. Intake of nutrients less than the Estimated Average Requirement (EAR) were identified as limiting nutrients in the participant groups' diets. In the next stage of the NutriShed framework, the target foods associated with supply of the priority nutrients were tracked to map their flow in and out of the study communities.
Stage II: Quantifying Nutrient Flows
The next step of the NutriShed approach focused on identifying and quantifying the flow of target foods (foods identified as having high content of priority nutrients) into our study communities. This process required surveys to collect primary data on (a) quantities of the different target foods being transported into our study sites (e.g., via road intercept surveys), (b) the range and characteristics of different food systems infrastructures located within the vicinity of our local communities (e.g., roads, food processing units and storage facilities), and (c) the conditions and characteristics of local markets for nutrient-dense foods receiving the inbound flows of our target foods within our study communities.
The first survey targeted food market actors including suppliers, commission agents, market managers, and market queens, operating at diverse locations: markets, lorry stations, food warehouses, and port facilities within the study communities. The aim of this survey was to collect data on the geographical origins, destinations, and sizes of food flows reaching the communities, as reported by local market actors. The surveys also gathered information on the number, capacities, and routes of traders, as well as the provenance, volumes, and types of nutrient-dense foods.
A second survey, focused on traders and market agents and targeted those transporting produce into the study communities using mobile-based survey techniques. These surveys were designed for rapid administration, taking only 5–10 minutes to collect data on the origins, destinations, and types of commodities flows as well as the quantity of food being transported.
A third survey, the road intercept survey, helped triangulate the first and second surveys. It tracked the movement of vehicles transporting food products in and out of major access roads. These surveys were conducted over a three-day period during each of the peak production seasons (July/August) and the lean season (February/March). Information collected from traders at the roadside included the sources and destinations of food loads, the overall weight, and the composition of commodities.
To support the triangulation of data, a spatial reference group was established at the study sites to help verify the sources, quantities, and seasonal variations of nutrient flows.
Stage III: Geospatial Toolkit
In stage II, the aim was to depict and characterise the Nutrisheds for both of our study sites (i.e., Takoradi and Asesewa) and across seasons (i.e., dry and wet seasons). Our analysis relied on previous literature on commodity specific Foodsheds (e.g., Karg et al 2016; Hemerijckx et al 2023; Karg et al 2023), first by considering the origins of multiple nutrient-foods rich in our four identified key limiting nutrients (i.e., iron, folic acid, calcium and Vitamin B12) - aggregated to the Nutrished level. We also focused on the characteristics of the Nutrished catchments with regards to the quantity and quality of food systems infrastructure (e.g., roads, population densities, storage and processing facilities), climate vulnerability, and variations across seasons (
Figure 3).
Further, we collected multiple sources of open-access geospatial data (raster or vector formats) to understand the wider food systems enabling environment associated with our study regions and across Ghana, more broadly. These datasets included national level land cover and land use from the remote sensing derived MERIS GlobCover dataset, the locations of different national and regional roads via OpenStreetMap, population hexagons for the country at 400 metre resolution via Kontur Population (available via United Nations Office for the Coordination of Humanitarian Affairs (OCHA) services), and estimates of the climate risk and conflict risk as determined by the Climate-Conflict-Vulnerability Index (CCVI) of the German Federal Foreign Office (
Table 1). These secondary datasets provide a canvas upon which to overlay the primary datasets from Stage II. This enabled analysis of road density, population density, and climate data in the study communities.
The primary data collected in Stage II required the digitisation of survey responses in order to be mapped. During the road intercept surveys, transporters were asked to provide the names of the production villages for each of the different items being transported, as well as the name of a nearby town to help triangulate the exact village (i.e., in case of multiple villages with the same name). The locations of production villages were then digitised in Microsoft Excel by exporting the latitudes and longitudes from Google Maps. Where villages were not present on Google Maps, we searched popular public mapping websites such as MapCarta, Latlong.net and Tageo. Where villages could not be located after the above two steps, we used the geo-coordinates of the nearby town associated with the production village that was provided during the intercept survey. Across both seasons and destinations, this process produced 770 records of food inflows (i.e., food item, quantities, transport modes etc) and 274 records of outflows.
These Excel datasets were then exported as Comma Separated Values (CSV) files readable as Delimited Text layers in the open access GIS software QGIS (v.3.28). From here, the Nutrisheds of each limiting nutrient were mapped using two of QGIS’s in-built geospatial processing functions, namely (i) ‘Join by lines (hub lines)’ - which provides straight line Euclidean geometry connections between source locations and destination locations (i.e., Asesewa and Takoradi), and (ii) the ‘Minimum bounded geography’ tool using ‘convex hull’ geometry - which creates a polygon representing the smallest region that encloses all of the source locations for a given limiting nutrient (e.g., iron) flowing towards our two study sites (i.e., Asesewa and Takoradi). Similar to a watershed, i.e., the topographic features which bound a river catchment, the convex hull here represents the catchment area bounding all sources of our limiting nutrients within the survey periods.
The previous steps mapped the flow of nutrients across space (i.e., from source to destination). We performed two further calculations to understand the spatial dimensions of the different Nutrisheds across seasons. First, the ‘Distance to nearest hub (Line to hub)’ tool calculates the Euclidean distance in kilometres between each source location and destination - estimating the minimum distances that each nutrient flow must travel to arrive at our study sites. This calculation generated information on how the cumulative quantities of nutrient supplies vary with distance from the study sites - thus depicting the dependency of Takoradi and Asesewa on local and/or distant food supplies. Second, to understand the orientation of the Nutrisheds, we used QGIS’s inbuilt trigonometric functions (i.e., ‘atan’ function) to calculate the directional bearing (i.e., 0-359°) of each Euclidean pathway between source and destination using the following equation in the QGIS field calculator:
Equation 1: AngleN, D, T = CASE WHEN ((yat(-1)-yat(0)) = 0 and (xat(-1) - xat(0)) >0) THEN 90 WHEN ((yat(-1)-yat(0)) = 0 and (xat(-1) - xat(0)) <0) THEN 270 ELSE (atan((xat(-1)-xat(0))/(yat(-1)-yat(0)))) * 180/pi() + (180 * (((yat(-1)-yat(0)) < 0) + (((xat(-1)-xat(0)) < 0 AND (yat(-1) - yat(0)) > 0)*2))) END.
Where N equals unique nutrient (i.e., iron, calcium, vitamin B12 and folic acid), D equals destination (i.e., Asesewa or Takoradi), T equals season (i.e., wet or dry), and yat and xat equal the latitude and longitude of the Euclidean pathways, respectively.
As a result of the above analyses, for each of the four limiting nutrients flowing into Asesewa and Takoradi, we are able to compare seasonal estimates of (i) the number of production sources and the associated catchment area, (ii) the variation in supply contributions against distance from Asesewa and Takoradi, and (iii) the directional dependency of nutrient inflows into our study sites.
Stage IV: Assessment of nutrient flow vulnerabilities
Stage IV of the Nutrished approach aims to provide insights for town and city planners into (a) the origins of the key limiting nutrients flowing into their communities, (b) the current usage of existing food system infrastructures (e.g., storage and processing facilities) within their communities, and (c) the potential vulnerability of the Nutrisheds to anthropogenic and/or climatic disruption. To this end, for each of the four Nutrisheds across the two study sites and two seasons, we quantify (i) all-weather road densities, (ii) climate risk, (iii) conflict risk, and (iv) the current congruence between the use of existing food system infrastructures and the needs of the limiting nutrient flows.
Unlike feeder road tracks that are vulnerable to being washed away during heavy rainfall events, all-weather roads provide relatively permanent and reliable transportation routes to connect producers with downstream consumers throughout the year (Rammelt and Leung 2017; Weatherspoon et al 2017). Therefore, as a proxy for the level of road connectivity between source locations and study communities, we calculated the density of all-weather roads within each Nutrished (km/1000 ㎢). As per OpenStreetMap data available via the online repository GeoFabrik, all-weather roads are considered as those labelled ‘primary’, ‘secondary’, or ‘tertiary’ classifications; as such, roads labelled as ‘track’, ‘residential’, ‘service’, ‘path’ and ‘bridleway’ are omitted from the analysis using the QGIS layer filter function. Lastly, road density was calculated by dividing the summed length (km) density of the three included road classifications within a particular Nutrished by the total area (㎢) of the Nutrished. Nutrisheds with comparatively low road densities are considered to be relatively vulnerable to poor connectivity, including a sparsity of alternative routes in case the primary route between source and destination is impassable (e.g., during a flood event).
Next, the climate and conflict risks of all Nutrisheds were quantified using georeferenced data from the Climate-Conflict-Vulnerability Index (CCVI) dataset of Mittermaier et al. (2025). Publicly available at 0.5° resolution, the CCVI integrates multiple global coverage datasets to quantify local climate and conflict risks across the entire globe. As detailed in Mittermaier et al (2025), the climate and conflict risks at any given point is a function of ‘climate/conflict exposure’ multiplied by ‘vulnerability’. ‘Climate exposure’ is a composite index of current (i.e. past three months) and accumulated (i.e. past 7 years) droughts, heatwaves, heavy precipitation, wildfires, floods and tropical cyclones, and the mean precipitation anomaly (past 30 years relative to 1951-1980 baseline), mean temperature change (past 30 years relative to 1850-1900 baseline), and relative sea level rise from 1993-2005. Next, ‘conflict exposure’ is a composite index of the intensity and persistence of (a) local conflict and (b) popular interest (i.e., protests and riots). Lastly, ‘vulnerability’ is a composite index constituting 14 indicators of socioeconomic (e.g., gender inequality, health vulnerability, economic deprivation), political (e.g., civil rights deprivation, ethnic marginalisation) and demographic (e.g., uprooted people, population growth) vulnerabilities. For our Nutrisheds, we use QGIS’s in-built ‘Distance to nearest hub (Line to hub)’ function to associate each production source with its nearest recorded data point for climate risk and conflict risk; in turn, for the catchment areas, the spatial ‘clip’ tool is used to subset the climate risk and conflict risk values located within the convex hull of each Nutrished catchment.
In addition to the nutrient flow data, we also analysed the geospatial data collected on the markets, storage and processing infrastructures for nutrients dense foods (NDFs) in Asesewa and Takoradi. In particular, we explored the number and type of different infrastructures (e.g., cold storages, regular storages, processing facilities, and collection centres), and documented the practices related to storage and/or processing nutrient-rich target food identified.
Stage V: Identify catchment level nutrition-sensitive strategies and interventions
Stage V employed Geographical Information Systems (GIS) techniques to examine the solution space of alternative interventions to boost nutrient supplies towards underserved study communities. The process involved analysing catchment area land-use and identifying potential for local production to bolster nutrient supply. We used spatial multi-criteria decision analysis to examine strategic locations for new markets or cold-storage facilities. This was followed by qualitative systems dynamic modelling to scope potential future (i.e., multi-decadal) trade-offs emerging from the solution space, including modelling the key feedback loops and system archetypes (Senge 1990) driving the distributions of nutrients, environmental impacts, and the participation of women and other underrepresented groups in NutriShed. A portfolio of strategies was then compiled for community stakeholder consideration.
Box 1.
Portfolio of identified strategies for improving food market system.
Box 1.
Portfolio of identified strategies for improving food market system.
Strategies to Improve local production (Takoradi)
Frequent interaction between farmers and extension officers
Increased demand for extension officers
Focus on Poultry and Green-leafy vegetables production systems
Training on improved Agronomic practices
Promotion of backyard farming
Integration of mandatory garden spaces into construction permits to encourage household level food production
Re-introduction of school-based farming programs
Establishment of cold rooms
Strategies to Improve local production (Asesewa)
Government subsidy for agricultural inputs
Depoliticization and continuation of Government initiatives targeted at boosting food production
Strengthening of agricultural extension staff capacity in the district
Public education by the district assembly on legitimate processes of acquiring land for farming in the district
Use of demonstration farms to train and teach farmers on innovative and cost-effective agricultural methods
Siting of storage facilities close to markets to encourage patronage
Strategies to Improve Healthy eating (Asesewa)Strategies to Improve Healthy eating (Takoradi)
Community education to address entrenched cultural food practices and eating habits that are unhealthy
Foster collaboration between faith-based organizations and health agencies to disseminate food and nutrition information
Promotion of healthier food choices and preparation methods at the household level
Solution to transport-related Challenges (Takoradi)
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VI. Engaging with stakeholders/reference groups
Throughout the project, we engaged with relevant community- and national-level experts, decision-makers, and key actors (Reference Group). To ensure effective participatory planning, and buy-in, two types of meetings were held with the Reference Groups in Asesewa and Takoradi. Reference Group members were selected based on their expertise, and roles in health, agriculture and education in their respective districts and at the national level.
The first Reference Group meeting involved national-level experts, community leaders, NGO actors, and academics. This meeting presented the project plan and solicited their input to ensure implementation feasibility, and to identify all relevant stakeholders to involve. The second Reference Group meeting brought together supply chain actors including traders and retailers—to discuss the perceived benefits and trade-offs of the proposed study. Subsequently, a broader range of stakeholders including the Reference Group, from each city, were engaged during the dissemination of the preliminary findings. This convening generated conversations around local production of nutrient rich foods, transportation and barriers to healthy eating. Stakeholders further highlighted the strategies they consider critical to address barriers to access food from local markets (see box 2).
Box 2.
Strategies that were considered critical to address barriers to access food from local markets.
Box 2.
Strategies that were considered critical to address barriers to access food from local markets.
Takoradi:
Lack of Agric extension support
High cost of agricultural inputs
Poor road networks
Urban land competition
Limited Storage facilities
Seasonality and climate unpredictability
Asesewa:
Cultural barriers to healthy eating
Unfavourable land tenure systems
Poor road networks
High cost of Agricultural inputs
Inadequate agricultural extension officers
Lack of food storage facilities
High cost of nutrient-rich foods
Limited financial capacity of trader
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