Participants with a low serum bicarbonate were more likely to be Australian Aboriginal and less likely to be Anglo-Celt, were younger at diagnosis of diabetes, had longer diabetes duration, higher fasting glucose and HbA1c, more intensive blood glucose-lowering treatment, greater obesity, higher heart rate, serum potassium, serum triglycerides, urinary albumin:creatinine ratio and prevalence of CHD and cerebrovascular disease, lower diastolic blood pressure, serum HDL-cholesterol and eGFR, and more comorbidities. Here, ALB is linked to obesity due to melanocortin 4 receptor deficiency.