Sydney: Calling for a radical rethinking of human nutrition science, scienists have developed a new framework called "nutritional geometry" which is the culmination of more than 20 years of research in the field. According to the authors, the new model will assist health professionals, dietitians and researchers to better understand and manage the complexities of obesity. The new model shows that protein has been the strongest driver influencing diet, regulating the intake of fat and carbohydrate. "Existing models for measuring health impacts of the human diet are limiting our capacity to solve obesity and its related health problems," said professor David Raubenheimer and professor Stephen Simpson from University of Sydney's Charles Perkins Centre. 'Nutritional geometry' considers how mixtures of nutrients and other dietary components influence health and disease, rather than focusing on any one nutrient in isolation. "Our framework shows that the prevailing focus on single nutrients is not able to help us understand complex chronic diseases and that an approach based on nutrient balance can help solve the problem," Simpson added. The traditional approach is no longer useful in the face of modern nutrition-related diseases which are driven by an overabundance of food, an evolved fondness for foods containing particular blends of nutrients, and savvy marketing. Conventional thinking which demonises fat, carbohydrate or sugar in isolation as causes of the obesity crisis - dubbed the single nutrient approach - has now run its course. "We've provided a framework for not only thinking about but also experimentally testing issues around dietary balance. Much like the invention of the telescope or microscope, this framework offers a new tool with which to look at complex dietary problems and bring them into focus," Simpson noted. The 'nutritional geometry' framework enables us to plot foods, meals, diets and dietary patterns together based on their nutrient composition and this helps researchers to observe otherwise overlooked patterns in the links between certain diets, health and disease. For the study, the duo plotted data for the composition of 116 diets, compiled from previous published studies examining macronutrient ratios (carbohydrate, fats and protein) and energy intake in humans. "The new approach provides a unique method to unify observations from many fields and better understand how nutrients, foods and diets interact to affect health and disease in humans," added professor Raubenheimer in a paper published in the journal Annual Review of Nutrition.