Lifestyle intervention strategies for diabetes management

Abstract

The inexorable rise of type 2 diabetes (T2D) worldwide is a serious public health problem with significant health and socioeconomic costs. Diabetes- related complications are underpinned by poor glycaemic control that is greatly influenced by diet composition. Sustainable lifestyle modifications in diet and physical activity form the cornerstone of T2D prevention and management. Energy- restricted, high unrefined carbohydrate, low fat (HC) diets have traditionally been recommended for the dietary management of T2D. However, accumulating nutrition research indicate that carbohydrate restriction and higher intakes of protein and unsaturated fats, improve glycaemic control and reduce cardiovascular disease (CVD) risk markers. Based on this evidence, a novel dietary approach incorporating a very low carbohydrate, high unsaturated fat/ low saturated fat (LC) diet was designed. This LC diet was nutritionally adequate, with the potential to improve glycaemic control and mitigate CVD risk to a greater extent than the traditional HC diet. This thesis discusses the findings of a large, well- controlled, randomised, clinical trial that compared the long- term effects of consuming a traditional HC diet with an energy- matched LC diet, on a range of health outcomes including glycaemic control and CVD risk markers. Both diets were delivered as part of a holistic lifestyle intervention that included a structured exercise program. After one year, both diets achieved substantial weight loss, and reduced blood pressure, HbA1c, fasting glucose and LDL-C. However, the LC diet sustained greater reductions in diabetes medication and glycaemic variability, as well as triglycerides (TAG), and greater increases in HDL-C. Both diets had similar changes in renal and cognitive outcomes, suggesting that the LC diet did not adversely affect renal or cognitive function. These results have important implications for the lifestyle management of T2D with direct relevance to achieving better health outcomes and reducing healthcare costs.