Reliable evidence of the nutritional composition of local species and varieties and the associated health benefits that this agricultural biodiversity provides is scarce.

Information on the nutritional quality/composition analysis of biodiversity for food and nutrition is still too limited in species and scale compared to the analysis that takes place for mainstream agricultural foods and their products, making it difficult for practitioners to scale up local interventions to national or global scales. One of the components of the Biodiversity for Food and Nutrition project is to work in the countries to provide enough evidence on the nutritional value of local agricultural biodiversity to ultimately enhance its conservation and sustainable use.

Good solid evidence is needed to persuade policy-makers that conserving biodiversity for nutrition, health and food security is essential and that locally-available food sources have the potential to provide the basis for cost-effective, food-based strategies to enhance micronutrient intakes or act as a complementary food for undernourished segments of the population.

Studies have shown that wherever nutrient composition data was available, confirming that local foods were more nutritious and healthier than their exotic counterparts, policy-makers were more prepared to include food-based approaches focusing on agricultural biodiversity in policies tackling malnutrition. This was achieved by issuing policies that favour the mobilization and use of local foods, while setting up strategies to limit the import of exotic foodstuffs (particularly sugars, fats and soft drinks). Similarly, where demonstrated evidence exists on the role of homegardens in contributing to improved household dietary diversity, food security and nutritional status (see Helen Keller International Homestead Food Production programme), governments have widely promoted these sustainable agricultural practices and scaled-up efforts to other food insecure areas, both nationally and regionally.

Evidence is also instrumental in creating markets for underutilized species. In the case of "forgotten crops" like maca, yacon and quinoa in Peru greater awareness of the nutritional attributes of these underutilised species helped increase market demand for these root crops, creating a virtuous circle for their greater use and consumption, including beyond national boundaries. Furthermore, the rapid rise of health food/organic markets in the developing world offers unprecedented opportunities for market placement of many of these niche crops that await “nutritional discovery”.