Will recognising links between biodiversity and human health lead to greater focus on the benefits of trees?
Wild indigenous fruit trees could lead to better health and nutrition across the globe, but their potential remains largely untapped as little attention has been given to their nutritional or economic value.
For the first time, the World Health Organization (WHO) and Convention on Biological Diversity (CBD) have formally come together to recognize the mutual dependencies of biodiversity and human health, announcing the upcoming publication of a State of Knowledge Review on Biodiversity and Health during the 12th meeting of the Conference of Parties (COP12) to the CBD in Pyeongchang, Korea.
The review will compile what is currently known about how biodiversity impacts on health – such as helping to prevent diseases and ill-health – and help to reaffirm the notion that the health of humans cannot be isolated from the health of ecosystems. Many scientists and nutritionists are hopeful this will lead to greater research and focus on the role of indigenous species in improving diets.
Among these are scientists from the World Agroforestry Centre who are contributing to the food and nutrition chapter of the review which will discuss how wild foods contribute to dietary diversity and nutrition. They intend to outline how trees provide direct and indirect benefits for human nutrition, including supplying fruits that have a high nutrient content, fuel wood that can be used to cook foods as well as possibilities for income generation and greater environmental stability in farming systems.
In particular, the scientists plan to highlight the potential for tree species to contribute to better diets; a potential which has been largely untapped due to scant information on the nutritive and economic value of wild and underutilized cultivated species.
Since agriculture began some 12,000 years ago, approximately 7,000 plant species and several thousand animal species have been used for human food. Today, certain traditional and indigenous communities continue to use 200 or more species in their diets but the general global trend has been towards diet simplification, with consequent negative impacts on human food security, nutritional balance and health.
In Africa, 70 per cent of people’s diets comprise staple ‘energy’ foods such as maize and rice. While the World Health Organization recommends 400 grams of fruit and vegetables be consumed daily, studies have found that in East Africa, people consume just 40g of these each day.
This low consumption of nutrients is not due to lack of availability. There are a wide range of native fruit trees that could provide nutrients above and beyond recommended quantities. For example, consuming 40 to 100g of berries from the native Grewia tenax could supply almost 100 per cent of a child’s (under 8 years of age) daily iron requirement. The fruits of Dacryodes edulis and the seeds of Irvingia gabonensis, Sclerocarya caffra and Ricinodendron rautanenii have a higher fat content than peanuts.
The African Baobab (Adansonia digitata) is an example of a wild fruit tree with vast potential to improve diets as well as contribute to rural livelihoods. Baobab grows in the savannas, scrublands and semi-deserts of sub-Saharan Africa. Its fruits contain far higher amounts of Vitamin C, calcium and iron than more common tropical fruits such as mango and orange. The leaves too can be eaten and are highly nutritious. Oil derived from the seeds can be consumed as well as used in cosmetics.
Baobab products for home consumption and sale have a great potential to support local communities in vulnerable dryland ecosystems and in the face of climate variability. They also offer a great opportunity for income generation, particularly for women who are involved in collection, processing and marketing of these products.
Baobab is just one of hundreds of wild food trees in Africa with a similar importance for food and nutrition security. But to realize the full potential of these trees, scientists from the World Agroforestry Centre believe there is an urgent need to compile data on their composition and find ways to ensure their nutritional elements are maintained in processing. Markets for new products also need further development and effective links made between processors and domestic and international markets.
The environment too stands to benefit from an increased usage of wild foods. If domestication and increased cultivation of tree species occurs, this will contribute to the diversification of farming systems and may help to conserve natural stands.
The State of Knowledge Review on Biodiversity and Health will analyse these and many other issues, forming part of the CBD’s technical series. The series intends to contribute to the dissemination of up-to-date and accurate information on topics that are important for the conservation of biological diversity, its sustainable use and the equitable sharing of its benefits.
In his statement at the opening of COP12, Braulio F. de Souza Dias, Executive Secretary of the CBD, outlined the need to mainstream biodiversity for health as an integrated issue on the international agenda, especially in relation to the Sustainable Development Goals currently being formulated.
Related story: The value of trees for food and nutrition
Find out more about the World Agroforestry Centre’s participation at CBD COP12