Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: David M Williams reports a relationship with AstraZeneca UK Limited that includes: speaking and lecture fees. David M Williams reports a relationship with Eli Lilly and Company that includes: travel reimbursement. Laura Wilkinson reports a relationship with Mondelez International UK Ltd that includes: funding grants. Laura Wilkinson reports a relationship with Huel Limited that includes: funding grants. Laura Wilkinson reports a relationship with Twisted Orange Ltd that includes: consulting or advisory. Thinzar Min reports a relationship with AstraZeneca UK Limited that includes: speaking and lecture fees and travel reimbursement. Thinzar Min reports a relationship with Boehringer Ingelheim Ltd that includes: speaking and lecture fees and travel reimbursement. Thinzar Min reports a relationship with Eli Lilly and Company that includes: speaking and lecture fees and travel reimbursement. Thinzar Min reports a relationship with Abbott Diabetes Care Inc that includes: speaking and lecture fees and travel reimbursement. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.