T2D and obesity: why treatment falls short

A review published in Expert Review of Clinical Pharmacology on 17 July 2026 poses a pointed question: if obesity is both a primary driver of type 2 diabetes and a barrier to managing it, why are so many patients receiving care that addresses glycaemia but not weight^[1]? The authors, a group of European endocrinologists and cardiologists, review the evidence and conclude that clinical practice has not kept pace with what the pharmacology now makes possible.

That pharmacology has shifted considerably. The 2022 ADA/EASD consensus on management of hyperglycaemia in type 2 diabetes called for a holistic approach that places weight management alongside glycaemic control, and recommended GLP-1 receptor agonists and SGLT-2 inhibitors based on cardiorenal outcomes data^[2]. Yet, the 2026 review finds, implementation has been inconsistent. Obesity remains underappreciated as a modifiable target in this patient group.

The scale of the overlap

The WHO reported in 2022 that 1 in 8 people worldwide were living with obesity and 2.5 billion adults were overweight^[5]. Type 2 diabetes and obesity co-occur at rates that are difficult to separate: excess adiposity drives insulin resistance, and insulin resistance accelerates weight gain. The 2026 review by Miličević Milardović and colleagues notes that current clinical guidelines place heavy emphasis on cardiovascular risk stratification but systematically underweight obesity as a treatment target in its own right^[1].

This matters for two reasons. First, many of the glucose-lowering drugs that have historically been used in type 2 diabetes are weight-neutral or weight-promoting. Insulin and sulfonylureas, both widely prescribed, can drive weight gain that offsets glycaemic benefit. Second, the evidence base now supports agents that address both problems simultaneously, yet uptake remains limited^[1].

What the 2026 review argues

The authors identify several barriers to weight-focused treatment in people with type 2 diabetes. Cost and reimbursement are prominent: the agents with the strongest weight-loss evidence, including dual GIP/GLP-1 receptor agonists like tirzepatide, are still expensive in most markets, and coverage criteria for weight management often differ from those for diabetes management^[1].

A second barrier is dosing. The review notes that doses approved for obesity treatment may be higher than those typically used for glycaemic control, and that prescribers sometimes default to lower diabetes-indication doses without considering the additional weight benefit available at higher doses^[1]. This is not a trivial distinction: the tirzepatide SURPASS-1 trial, which studied the drug as monotherapy in type 2 diabetes, found dose-dependent weight reductions ranging from 7.0 kg to 9.5 kg at the three doses tested^[3]. The SURMOUNT-1 obesity trial, by contrast, showed mean weight reductions of 15.0% to 20.9% in people without diabetes at comparable dose levels^[4]. The pharmacology leaves room for more ambitious weight targets in type 2 diabetes patients than are currently being pursued.

A third barrier is what the authors describe as a tendency to treat diabetes and obesity as separate clinical problems requiring separate specialist referrals, rather than as a single metabolic syndrome requiring an integrated strategy^[1]. This fragmentation delays access to weight-focused therapy and leaves glycaemic management incomplete.

What the SURPASS programme showed

The SURPASS-2 trial put the combined glycaemic and weight benefit on display most clearly. In 1,879 patients with type 2 diabetes, tirzepatide at 5, 10, and 15 mg weekly produced HbA1c reductions of 2.01, 2.24, and 2.30 percentage points respectively, compared with 1.86 points for semaglutide 1 mg weekly at 40 weeks^[4]. Weight reductions favoured tirzepatide by 1.9, 3.6, and 5.5 kg across the three doses versus semaglutide^[4].

Those are head-to-head differences in a trial population. The SURPASS programme cannot be used to argue that any individual patient will achieve a specific outcome. But the data does establish that in type 2 diabetes, choosing an agent partly on the basis of its weight effect is justified by evidence, not just by marketing. A comparison of cardiovascular outcomes data across the GLP-1 class shows how the choice of agent carries meaningful downstream consequences beyond glycaemia.

Equity and access: the unresolved question

The 2026 review places access and equity concerns at the centre of the problem, not at the periphery^[1]. Disparities in coverage mean that patients with lower incomes, or those in healthcare systems with restricted formularies, are less likely to receive the agents with the strongest evidence for weight management alongside glycaemic control. The authors call for a multidisciplinary response that includes policymakers and payers, not just prescribers.

This concern is not specific to any one country. GLP-1 receptor agonists appear on the 2025 WHO Essential Medicines List, but appearance on that list does not automatically translate into affordable access in lower-income settings. In higher-income markets, even where reimbursement exists for the diabetes indication, obesity management indications often carry separate and more restrictive coverage criteria. The GLP-1 discontinuation literature suggests that cost is one of the most cited reasons patients stop treatment before reaching maintenance dose.

What this means in clinical terms

The 2026 review does not call for universal prescription of the highest-dose weight-management agents in everyone with type 2 diabetes. What it argues is that clinicians should assess and document obesity as an active treatment target, select agents based on the combined profile of glycaemic and weight benefit where both are relevant, and not leave weight management unaddressed simply because it requires a separate referral or a higher dose^[1].

The ADA/EASD 2022 consensus points in the same direction, recommending that overweight and obesity management be integrated into the routine care plan for type 2 diabetes^[2]. The gap between that recommendation and common practice is what the 2026 review is trying to close.

What we do not yet know

The review is a narrative analysis, not a systematic review or meta-analysis. The authors draw on published trial data and guideline documents rather than pooling primary data across studies. The barriers they identify, including cost, fragmented care, and dosing conservatism, are real and documented elsewhere, but the review does not quantify how large the treatment gap is or how much of it is attributable to each barrier. Prospective implementation data from health systems that have adopted integrated obesity/diabetes care pathways would be valuable and is largely absent from the literature. A related question is how GLP-1 weight-loss outcomes differ between people with and without type 2 diabetes, which is explored in a separate analysis of 56,580 patients.

This article is for informational purposes only and does not constitute medical advice. Decisions about treatment, including medication selection and dosing, should be made in consultation with a qualified healthcare provider who knows your individual history and circumstances.