 Many countries face an epidemic of obesity due to increased fast food consumption and sedentary lifestyles. Nuclear science can help policymakers understand and improve the nutrition of their people. For example, Mauritius has one of the highest obesity rates in Africa and has turned to nuclear techniques to tackle this issue. We know that diet is a risk factor for all non-communicable diseases, be it diabetes, cardiovascular diseases, hypertension and of course cancer as well. Non-communicable diseases are responsible for 89% of deaths in Mauritius. Diabetes is responsible for 24% of these deaths, while cancer kills approximately 12%. Diet and lack of physical activity coupled with increased life expectancy are major culprits for the rise of these diseases. In Mauritius, there are breast cancer, colorectal cancer, endometrial cancer. Those cancers that are diet related or even obesity related cancers, Mauritius has the highest rank in Africa. The IAEA help Mauritius use more precise tools to measure the impact of non-communicable diseases. Dr. Junas at the Central Health Laboratory is leading several studies using nuclear techniques. We decided to link the overweight and obesity problem with these non-communicable diseases. We started measuring body composition by stable isotope techniques. In 2009, the laboratory began to look at the extent of obesity in children. They wanted to find out at which point children started to become overweight and what health risks this could bring. They carried out studies in children aged 6 to 13 years using a technique known as deuterium dilution. The deuterium dilution technique is a very precise technique because it's actually giving you the fat mass and the fat free mass. The method paints a more accurate picture of body composition than measurements such as the body mass index or BMI. It works by drinking a heavy water, enriched with deuterium, an isotope, or variation of the element hydrogen. The deuterium mixes with a body's water pool after a few hours. Saliva samples are then collected and sent to a laboratory to measure its concentration. This allows scientists to calculate the total amount of water in the body. From there, they can estimate the fat mass and fat free mass. The study showed that more children than expected had excessive body fat and at an earlier age. It also showed that chronic disease could be just around the corner for many young people. We did find an increase in insulin resistance in our children so this means that they are already predisposed to have non-communicable diseases, especially diabetes. The results helped to boost existing nutrition policies. A tax on sugar was increased along with stricter controls on food sold at schools. We have also introduced guidelines for the school canteens to introduce the school aged children to the importance of having a healthy diet. The government started to provide school children in low-income areas with a balanced lunch and increased physical activity from once a week to every day. They also stepped up free nutrition counselling for the general population. You know when you're in that phase of prediabetes, it is reversible but once you become diabetic it is irreversible. Mauritius has since expanded the studies to different population groups. Along with deuterium dilution, the laboratory started to use a special type of x-ray to study the link between body composition, insulin resistance and cancer. These DEXA scans provide information on body fat distribution. This is important since fat around the organs or visceral fat carries a greater risk for chronic diseases. Many countries now face a double burden of malnutrition. There's under-nutrition on the one hand but also overweight, obesity alongside myconeutrient deficiencies. The IAEA helps countries use nuclear science to get the data they need for better nutrition policies so that everyone can have a healthier life.