The relationship between forest cover and diet quality: a case study of rural southern Malawi

Even low levels of tree cover improve dietary quality in West Africa

Forests are attracting attention as a promising avenue to provide nutritious and "free" food without damaging the environment. Yet, we lack knowledge on the extent to which this holds in areas with sparse tree cover, such as in West Africa. This is largely due to the fact that existing methods are poorly designed to quantify tree cover in drylands. In this study, we estimate how various levels of tree cover across West Africa affect children's (aged 12-59 months) consumption of vitamin A-rich foods. We do so by combining detailed tree cover estimates based on PlanetScope imagery (3 m resolution) with Demographic Health Survey data from >15,000 households. We find that the probability of consuming vitamin A-rich foods increases from 0.45 to 0.53 with an increase in tree cover from the median value of 8.8 to 16.8% (which is the tree cover level at which the predicted probability of consuming vitamin A-rich foods is the highest). Moreover, we observe that the effects of tree cover vary across poverty levels and ecoregions. The poor are more likely than the non-poor to consume vitamin A-rich foods at low levels of tree cover in the lowland forest-savanna ecoregions, whereas the difference between poor and non-poor is less pronounced in the Sahel-Sudan. These results highlight the importance of trees and forests in sustainable food system transformation, even in areas with sparse tree cover.

Deforestation reduces fruit and vegetable consumption in rural Tanzania

Two billion people across the planet suffer from nutrient deficiencies. Dietary diversification is key to solving this problem, yet many food and nutrition security policies, especially in low- and middle-income countries, still focus on increasing agricultural production and access to sufficient calories as the main solution. But calories are not all equal. Here, we show how deforestation in Tanzania caused a reduction in fruit and vegetable consumption (of 14 g per person per day) and thus vitamin A adequacy of diets. Using a combination of regression and weighting analyses to generate quasi-experimental quantitative estimates of the impacts of deforestation on people’s food intake, our study establishes a causal link between deforestation and people’s dietary quality.

Strategies to improve food and nutrition security continue to promote increasing food via agricultural intensification. Little (if any) consideration is given to the role of natural landscapes such as forests in meeting nutrition goals, despite a growing body of literature that shows that having access to these landscapes can improve people’s diets, particularly in rural areas of low- and middle-income countries. In this study, we tested whether deforestation over a 5-y period (2008–2013) affected people’s dietary quality in rural Tanzania using a modeling approach that combined two-way fixed-effects regression analysis with covariate balancing generalized propensity score (CBGPS) weighting which allowed for causal inferences to be made. We found that, over the 5 y, deforestation caused a reduction in household fruit and vegetable consumption and thus vitamin A adequacy of diets. The average household member experienced a reduction in fruit and vegetable consumption of 14 g⋅d⁻¹, which represented a substantial proportion (11%) of average daily intake. Conversely, we found that forest fragmentation over the survey period led to an increase in consumption of these foods and dietary vitamin A adequacy. This study finds a causal link between deforestation and people’s dietary quality, and the results have important implications for policy makers given that forests are largely overlooked in strategies to improve nutrition, but offer potential “win–wins” in terms of meeting nutrition goals as well as conservation and environmental goals.

The Future of Food: Domestication and Commercialization of Indigenous Food Crops in Africa over the Third Decade (2012–2021)

This paper follows the transition from ethnobotany to a deeper scientific understanding of the food and medicinal properties of African agroforestry tree products as inputs into the start of domestication activities. It progresses on to the integration of these indigenous trees as new crops within diversified farming systems for multiple social, economic and environmental benefits. From its advent in the 1990s, the domestication of indigenous food and non-food tree species has become a global programme with a strong African focus. This review of progress in the third decade is restricted to progress in Africa, where multi-disciplinary research on over 59 species has been reported in 759 research papers in 318 science publications by scientists from over 833 research teams in 70 countries around the world (532 in Africa). The review spans 23 research topics presenting the recent research literature for tree species of high priority across the continent, as well as that in each of the four main ecological regions: the humid zone of West and Central Africa; the Sahel and North Africa; the East African highlands and drylands; and the woody savannas of Southern Africa. The main areas of growth have been the nutritional/medicinal value of non-timber forest products; the evaluation of the state of natural resources and their importance to local people; and the characterization of useful traits. However, the testing of putative cultivars; the implementation of participatory principles; the protection of traditional knowledge and intellectual property rights; and the selection of elite trees and ideotypes remain under-researched. To the probable detriment of the upscaling and impact in tropical agriculture, there has been, at the international level, a move away from decentralized, community-based tree domestication towards a laboratory-based, centralized approach. However, the rapid uptake of research by university departments and national agricultural research centres in Africa indicates a recognition of the importance of the indigenous crops for both the livelihoods of rural communities and the revitalization and enhanced outputs from agriculture in Africa, especially in West Africa. Thus, on a continental scale, there has been an uptake of research with policy relevance for the integration of indigenous trees in agroecosystems and their importance for the attainment of the UN Sustainable Development Goals. To progress this in the fourth decade, there will need to be a dedicated Centre in Africa to test and develop cultivars of indigenous crops. Finally, this review underpins a holistic approach to mitigating climate change, as well as other big global issues such as hunger, poverty and loss of wildlife habitat by reaping the benefits, or ‘profits’, from investment in the five forms of Capital, described as ‘land maxing’. However, policy and decision makers are not yet recognizing the potential for holistic and transformational adoption of these new indigenous food crop opportunities for African agriculture. Is ‘political will’ the missing sixth capital for sustainable development?

Dietary diversity and its determinants among Khasi and Garo indigenous women (15 to 49 years) in Meghalaya, northeast India

BACKGROUND

Despite generally high agrobiodiversity, the Khasi and Garo indigenous people in Meghalaya have poor nutritional status among children and women.

AIM

To assess the dietary diversity of the Khasi and Garo indigenous women of reproductive age in Meghalaya, while examining the associated factors that affect it and to map the diversity of local food plants.

METHODS

A dietary survey was conducted through 24-hour recall with 276 women from 28 villages of Meghalaya. The mapping of local food plants was conducted through key informant interviews and focus group discussions in the same villages.

RESULTS

The mean minimum dietary diversity for women is 4.22 (SD ±1.26); with one-third (37%) of the women attaining a minimum dietary diversity of five or more food groups in a day. There were significant differences in the dietary diversity among the indigenous groups, the Garo community attaining higher minimum dietary diversity for women. There was also an inverse association between the number of land uses and dietary diversity. The mean number of food plants (including crop varieties) found in each village is 203 (SD±45.7).

CONCLUSIONS

There is potential to enhance dietary diversity through diversifying lesser consumed crops such as vitamin A-rich vegetables and fruits, nuts, seeds and green leafy vegetables in existing land holdings. Also, proper management and access to the commons will provide a sustainable resource base for diet and food security, enhance dietary diversity and bridge the hidden hunger among children and women.

Effects of Indigenous Diet Iron Content and Location on Hemoglobin Levels of Ghanaians

Multiple studies have demonstrated strong links between diet and anemia, but few have explored the impact of food groups on hemoglobin (Hb). We analyzed the correlation between Ghanaian diet and Hb levels to explore reduction of anemia prevalence through dietary interventions. Demographics, food frequency questionnaires (FFQ), and blood samples were obtained from 140 volunteers (ages 18–65) in five locations across Ghana. Hb was measured; estimated iron consumption was calculated. FFQ items were grouped by food type, and a regression analysis was performed to determine the most important dietary predictors of Hb. Moreover, 47% of total participants were anemic; 64% of females and 28% of males. Hb levels were highest in Mole (13.9 g/dL, SD = ±1.9), independent of sex distribution. The regression model revealed a 62.7% adjusted correlation between food groups and Hb levels. Animal foods (β = 0.016, t = 5.08, p < 0.01) and plant protein (β = 0.013, t = 2.86, p < 0.01) were the most influential groups to Hb levels. It is of vital importance to emphasize the benefits of consuming animal foods and plant proteins within the Ghanaian population. The ease of access to plant proteins makes it likely that this food group will be most influential and have the greatest impact in reduction of anemia in the Ghanaian population.

Conceptual Links between Landscape Diversity and Diet Diversity: A Roadmap for Transdisciplinary Research

Malnutrition linked to poor quality diets affects at least 2 billion people. Forests, as well as agricultural systems linked to trees, are key sources of dietary diversity in rural settings. In the present article, we develop conceptual links between diet diversity and forested landscape mosaics within the rural tropics. First, we summarize the state of knowledge regarding diets obtained from forests, trees, and agroforests. We then hypothesize how disturbed secondary forests, edge habitats, forest access, and landscape diversity can function in bolstering dietary diversity. Taken together, these ideas help us build a framework illuminating four pathways (direct, agroecological, energy, and market pathways) connecting forested landscapes to diet diversity. Finally, we offer recommendations to fill remaining knowledge gaps related to diet and forest cover monitoring. We argue that better evaluation of the role of land cover complexity will help avoid overly simplistic views of food security and, instead, uncover nutritional synergies with forest conservation and restoration.