The terms of reference for the working group were to review the evidence on lower carbohydrate diets (alongside higher fat and/or higher protein) compared with the current government advice for adults with type 2 diabetes (T2D); consider the impact, in adults with T2D, of lower compared with higher carbohydrate diets on markers and clinical outcomes of T2D including any potential adverse effects and make recommendations based on the review of the evidence. Its remit did not include consideration of the wider management of T2D, studies of children, people with pre-diabetes, type 1 diabetes or gestational diabetes.