Diabetes mellitus is a major global health issue, a lifelong disease for its sufferers and a complex multi-organ pathology. The optimisation of its prevention and treatment is of paramount importance. Since his medical student years, Dr Borg has pursued an interest in research, contributing to the development of the concept of protein ‘preloads’ to manage type 2 diabetes (T2D), which has been implemented internationally. This was followed by investigations that characterised the gastrointestinal effects of metformin, the most widely prescribed drug treatment for T2D, which are key to its glucose-lowering and blood pressure-regulating effects. This study was the first to identify the potential to repurpose metformin to treat postprandial hypotension, an underrecognised pathology common amongst sufferers of diabetes mellitus. More recently, Dr Borg has evaluated the potential mechanisms underlying variation in the glucose-lowering effects of metformin with altered timing of administration, and led research into understanding the burden of gastrointestinal symptoms in type 1 diabetes mellitus. 

Non-sugar sweeteners are widely and increasingly added to foods as a substitute for sugar. However, recent population studies have associated their habitual use with increased risk of T2D without fully elucidated mechanistic pathways. Furthermore, any differential effects between the various types of sweeteners are not fully understood. Dr Borg's PhD is titled "The metabolic effects of artificial sweeteners in health and type 2 diabetes," and he is currently leading two randomised control trials to inform society and support public health policy.