Obesity is the new ‘silent killer’ in Africa. Rapid changes in dietary habits, lifestyle, and lack of physical activity have led to rising rates of obesity, diabetes, hypertension and high blood pressure in African countries. More than one-third of African women (38.6%) and about a quarter of African men (22.9%) are estimated to be overweight (2014[1]). The number of overweight children under 5 in Africa has increased by more than 50% since 2000[2]. According to the Regional Office for Africa (WHO-AFRO), the increasing burden of chronic non-communicable diseases (NCDs), particularly in the WHO African Region, threatens to overwhelm already over-stretched health services. Indeed, obesity is associated with several chronic diseases such as type 2 diabetes, cardiovascular diseases, and some types of cancer. These health disorders challenge the health systems and absorb substantial amounts of resources. In Africa, NCDs accounted for 2.5 million premature deaths per year in 2012, with the highest age-standardised NCD mortality rate of all WHO regions (625 per 100,000 population)[3]. These figures are projected to rise, adding to the already high burden of communicable diseases.
At the request of twelve Member States in the Africa region (Benin, Ghana, Kenya, Mali, Mauritius, Morocco, Namibia, Senegal, South Africa, Tunisia, Uganda and United Republic of Tanzania), an IAEA technical cooperation project[4] has been carried out between 2012 and 2016 with the aim of building capacities in the use of stable isotope techniques to assess body fat, total energy expenditure and physical activity. The end goal was to enable better design of, and improvements to, national nutrition and health interventions to prevent and control obesity and related health risks (such as diabetes) among children in Africa.
Stable isotope techniques provide accurate, more reliable information on the magnitude of overweight and obesity based on body composition, and on the physical activity levels of school children. As they are more accurate than widely used population-level methods, the stable isotope techniques can be used to validate these population-level measures of body size (Body Mass Index (BMI)-for-age, waist to height ratio) and physical activity (questionnaires and accelerometry). Stable isotope techniques are safe, accurate and suitable for use in field settings. All countries participating in the project developed or strengthened capacities in the use of stable isotopes, and completed or are about to complete data collection and analysis.
The regional project also facilitated an exchange of experiences across the region, as well as the creation of a regional consortium ‘ROUND-IT’ (Reducing Obesity Using Nuclear techniques to Design Interventions in Africa) that will compile individual Member State data in a pooled database for further analysis. ROUND-IT will continue to work on obesity and physical activity in the context of non-communicable diseases beyond the completion of the project. Some results have already been published and more publications are in preparation.
