Clinical Practice Guide for Integrating Diabetes-Specific Nutri-tional Formulas into Diabetes Care: Evidence Review and Ex-pert Consensus

1. Introduction

Type 2 diabetes (T2D) is a growing global health concern, and effective nutrition management plays a critical role in improving glycaemic outcomes and reducing the risk of diabetes-related complications. Lifestyle interventions, including diet, exercise and associated reduction in adipose tissue, are recommended as first-line therapy for glycaemic management of T2D [1,2]. However, only approximately half of all people with T2D are able to follow the standard dietary and lifestyle advice due to various barriers, including access to affordable nutritious food, knowledge and skills for food preparation, time pressures, cultural and religious preferences, frailty, energy and appetite levels [3,4,5,6]. These challenges may contribute to the mean HbA1c in Australians with T2D remaining over 8% (higher than the target of 7% or below) over the last decade, despite significant advances in management and medications [7]. Australian Institute of Health and Welfare 2019-2020 data revealed 52% of adults with T2D had HbA1c results above the recommended targets [8].

Approximately 45% of people with T2D have multiple micronutrient deficiencies [9]. Multiple factors contribute to nutritional deficiencies in people with diabetes, including altered protein metabolism, increased fluid losses, impaired nutrient absorption, and inadequate or imbalanced dietary intake. Restrictive eating patterns further exacerbate these risks. In addition, diabetes treatments such as metformin, incretin-based therapies, including glucagon-like peptide-1 receptor agonists [GLP-1 RAs] and dual glucose-dependent insulinotropic polypeptide/GLP-1 receptor agonists [GIP/GLP-1 RAs]; and bariatric surgery can also precipitate or worsen micronutrient deficiencies [10]. The consequences of these nutritional deficiencies include destabilised glucose management [11], fatigue, lethargy, weakness and diabetes-related sarcopenia due to inadequate protein and micronutrient intakes [8]. These consequences can further exacerbate barriers to utilising the wholefoods dietary approach [12], emphasising the importance of tailored nutrition strategies to support the complex dietary needs of people with diabetes. The clinical relevance of sarcopenic obesity and sarcopenic diabetes is increasingly recognised as an unmet priority in diabetes care [13].

A recent expert consensus statement, with representatives from key diabetes stakeholders including the Australian Diabetes Society (ADS) and the Australian Diabetes Educators Association (ADEA), suggested Diabetes Specific Nutritional Formula (DSNF) as a simple and practical way to support people with T2D in optimising their nutritional intake, improving glycaemic management and overall health outcomes when wholefood options are not feasible or not achieving desired outcomes [3]. DSNF are a specialised oral nutritional supplement, formulated to support blood glucose management and nutritional needs for people with diabetes and/or impaired glucose tolerance (pre-diabetes). They have been shown to improve glycaemic management [6,14,15,16,17,18,19], nutritional status, weight management, body composition, and cardiometabolic health [14,18,19]. A meta-analysis (18 studies; n=845) found that compared to standard oral nutrition formulas, DSNF treatment in people with diabetes led to improvements in postprandial glucose, incremental glucose response, plasma insulin, mean blood glucose level, glycosylated haemoglobin (HbA1c), glucose variability, and mean administered insulin dose [18]. In a 90-day intervention study, those using DSNF had a twofold greater weight loss ( −1.74 kg vs. –0.76 kg, p < 0.001) compared to usual care. Importantly, the DSNF group also had a significantly greater loss of visceral adipose tissue (−6.52% vs. –0.95%) compared to usual care, while gaining twice as much fat-free mass (1.44% vs. 0.79%) [19]. The magnitude of these effects suggests meaningful benefits for glycaemic regulation, metabolic health, and body composition, supporting the use of DSNF as an evidence-based adjunct to conventional dietary approaches. However, limited health professional awareness and understanding of the benefits and practicalities of when and how to use DSNF remain barriers to their use [3,20,21]. This paper aims to present the rationale, development process, and core components of a national CPG that provides evidence-based direction for health professionals on incorporating DSNF into diabetes care. The primary focus of this CPG is type 2 diabetes, where the majority of evidence supporting the use of DSNF exists. While DSNF use has also been studied in other populations, including type 1 diabetes, gestational diabetes, and prediabetes, the evidence base in these groups is emerging [22,23,24,25,26]. Accordingly, recommendations for these populations should be applied with appropriate clinical judgment and consideration of individual clinical context.

2. Materials and Methods

To inform the development of this CPG, an expert working group was formed in April 2025 to build on the previously published consensus statement and develop this CPG using a structured, evidence-informed and consensus-based methodology, consistent with established approaches to guideline development in these areas. Development of the CPG followed structured consensus methods consistent with internationally recognised guidance frameworks, including the World Health Organisation Handbook for Guideline Development and National Institute for Health and Care Excellence guideline development principles [27,28].

2.1. Literature Review

A scoping literature review was undertaken by the working group to summarise the current evidence on DSNF and to inform the structure and content of the initial draft guidance. The review aimed to map the breadth of available evidence rather than to conduct a formal systematic review.

Searches were conducted for studies published between January 2010 and June 2024 using PubMed, Embase, and Google Scholar. Search strategies combined terms related to DSNF with terms relating to diabetes type and relevant clinical outcomes. Key search terms included, but were not limited to: “diabetes-specific nutritional formula”, “diabetes-specific formula”, “glycaemia-targeted specialised nutrition”, “specialised nutrition formula”, AND “type 2 diabetes”, “type 1 diabetes”, “gestational diabetes”, “prediabetes”, AND “glycaemic control”, “HbA1c”, “weight management”, “body composition”, “nutritional status”, “cardiometabolic risk”.

An example PubMed search strategy was:

("diabetes-specific nutritional formula"[tiab] OR "diabetes-specific formula"[tiab] OR "glycaemia-targeted specialised nutrition"[tiab] OR "glycemia-targeted specialized nutrition"[tiab] OR "specialised nutrition formula"[tiab] OR "specialized nutrition formula"[tiab] OR "diabetes formula"[tiab] OR "diabetes-specific oral nutrition supplement"[tiab] OR "oral nutrition supplement"[tiab] OR "medical nutrition therapy formula"[tiab] OR "enteral nutrition"[MeSH] OR "food, formulated"[MeSH])

AND

("type 2 diabetes"[tiab] OR "type 1 diabetes"[tiab] OR "gestational diabetes"[tiab] OR "prediabetes"[tiab] OR "Diabetes Mellitus, Type 2"[MeSH] OR "Diabetes Mellitus, Type 1"[MeSH] OR "Diabetes, Gestational"[MeSH] OR "Prediabetic State"[MeSH])

AND

( "glycaemic control"[tiab] OR "glycemic control"[tiab] OR "HbA1c"[tiab] OR "weight management"[tiab] OR "body composition"[tiab] OR "nutritional status"[tiab] OR "cardiometabolic risk"[tiab] OR "Hemoglobin A, Glycosylated"[MeSH] OR "Body Composition"[MeSH] OR "Nutritional Status"[MeSH] OR "Blood Glucose"[MeSH])

Equivalent terms and controlled vocabulary (e.g., MeSH and Emtree terms) were used where applicable in PubMed and Embase. Google Scholar searches were used to identify additional relevant studies and recent publications not yet indexed in bibliographic databases. Searches were limited to human studies published in English. Evidence types included randomised controlled trials, observational studies, secondary analyses, and relevant systematic reviews.

Studies were included if they involved adults with diabetes or prediabetes and evaluated the effects of DSNFs on relevant clinical or nutritional outcomes. This included studies involving adults with type 2 diabetes, type 1 diabetes, gestational diabetes, or prediabetes. Exclusion criteria included animal studies, non-English publications, paediatric populations, and interventions not related to DSNF use. Evidence from included studies was synthesised narratively, with emphasis on study design, sample size, and clinical relevance. No formal evidence-grading framework was applied in this version of the guide.

2.2. Consensus Development

Following the literature review, a structured Consensus Development Workshop was conducted using established approaches such as the RAND/UCLA Appropriateness Method and formal consensus techniques [29,30]. Experts representing key disciplines contributed to small-group discussions, voting rounds, and thematic review of recommendations. Consensus on each recommendation required a minimum agreement threshold of ≥80%. Areas of agreement and divergence were documented, refined through written feedback, and finalised across multiple review cycles to ensure methodological rigour and alignment with best-practice consensus frameworks.

The expert working group included representatives from the ADS, ADEA, and Royal Australian College of General Practitioners (RACGP) as well as independent experts in their fields. This diverse, multidisciplinary team included experts across primary care, nutrition and dietetics, diabetes education, pharmacy, nursing, endocrinology, and research, ensuring the CPG is informed by published literature, expert consensus, and clinical experience, and is practical and applicable to real-world clinical practice.

The overall aim of this CPG is to inform health professionals with evidence-based guidance, supporting them to confidently integrate DSNF into the management of diabetes, with a focus on T2D or those at risk, in clinical practice. The target audience for this CPG is any health professional involved in the diabetes care pathway, including but not limited to General Practitioners, Dietitians, Diabetes Educators, Pharmacists, Nurse Practitioners, Endocrinologists, Exercise Physiologists, Geriatricians, and Practice Nurses. Engaging a multi-disciplinary audience is important to ensure that people with diabetes receive consistent guidance from all members of their healthcare team, enhancing the patient experience and increasing the likelihood of beneficial outcomes [31,32,33,34]. This DSNF CPG is intended to be used in conjunction with existing guidelines, including the ADS T2D Glycaemic Management Algorithm [1], ADS Obesity Treatment Algorithm [35], and the RACGP Management of Type 2 Diabetes: A handbook for General Practice Guidelines [36]. Please note, the sponsor had no role in evidence appraisal, consensus development, or manuscript preparation.

3. Results

3.1. What are DSNF?

DSNF feature slow-release, low glycaemic index (GI) carbohydrates, high-biological value protein, healthy monounsaturated (MUFAs) and/or polyunsaturated fatty acids (PUFAs), added dietary fibre, vitamins and minerals, delivered in kilojoule-controlled portions.

DSNF can be used irrespective of body weight and tailored according to an individual’s needs. They can be used as partial replacements for selected eating occasions in those with healthy weight and body composition, low-kilojoule replacements for two eating occasions for those who carry excess adipose tissue, or nutritional supplements as determined by appropriate health professionals [3]. Their specific formulation and versatility across multiple clinical scenarios, regardless of body weight, distinguish DSNF from very low energy diets (VLED) and standard oral nutrition supplements (ONS) (Table 1) [3,37,38].

3.2. Steps to Implementing DSNF in Practice.

The steps of the CPG are shown in Figure 1. The companion to the guide, which includes additional details, is included in the Supplementary Material (S1).

3.2.1. Step 1: Assess Suitability

DSNF are a valuable tool primarily indicated for people with T2D, but they may also be suitable for those with type 1 and gestational diabetes, or impaired glucose tolerance (pre-diabetes), noting that the evidence base in these populations is emerging and application should be guided by clinical judgment [22,23,24,25,26]. They are particularly useful when a wholefood dietary approach is not achieving glycaemic targets (e.g., HbA1c) or is not always feasible. DSNF can assist in overcoming common barriers to healthful nutrition, including supporting people who are time-poor, travelling, overwhelmed or anxious about managing their condition, low in health literacy, limited in cooking skills, low appetite, post-surgery, or are dealing with another acute or chronic illness.

Additionally, they can support individuals whose current dietary intake does not meet recommended nutritional requirements. This may include people with low appetite, those recovering from surgery, older adults with frailty, individuals after acute illnesses or with chronic illnesses, or those using diabetes medications, such as Sodium-Glucose Transport 2 (SGLT2) inhibitors and incretin-mimetic medications (e.g. GLP-1 RAs and GIP/GLP-1 RAs), which are associated with loss of lean mass including skeletal muscle [14,39]. Importantly, DSNF can be used in people with a range of body weights and compositions, including those with excess adiposity, those of ‘healthy’ weight and those who are underweight [21].

DSNF are generally not recommended for people who have allergies or intolerances to any of the product’s ingredients, follow cultural dietary practices that may not align with the formula’s composition, or have other specific medical needs that may preclude use. They may not be necessary if a wholefoods diet is followed consistently.

3.2.2. Step 2: Tailor the Approach

To ensure effective and person-centred use of DSNF, it is necessary to discuss and prioritise the individual's goals. These may include improving glycaemic management, supporting nutritional intake, reducing body fat, achieving a healthy body weight, improving muscle mass, increasing energy levels and reducing cardiovascular risk [3,27,40].

Once goals are identified, a personalised DSNF plan should be developed based on weight- and body-composition related goals. For fat mass reduction, a common approach is to use two servings per day to replace main meals (for example, breakfast and lunch). Or, if the individual currently includes snacks in their meal plan, a snack may be replaced (for example, breakfast and afternoon tea). For weight maintenance, one serving per day may be sufficient, replacing all or part of a main meal or another, smaller eating portion such as a snack. For those aiming to gain weight, two servings per day may be added between main meals, for example, morning and afternoon tea, as a nutritional supplement to boost energy and nutrient consumption [32]. DSNF should always be used as part of a broader diabetes management plan.

DSNF reduce glucose variability [41]. For maximum impact, it is recommended that meal timing should be individualised. For example, if blood glucose excursions consistently occur after specific eating occasions, consider using a DSNF to replace the food/snack that leads to the highest excursions. If hypoglycaemia is more of a concern, DSNF may potentially be used as a snack prior to the expected low blood glucose to help stabilise blood glucose levels [42]. For example, where a person is at risk of nocturnal hypoglycaemia while sleeping, a DSNF may be added as an ‘evening supplement’ to help reduce the risk. If blood glucose patterns are unknown, breakfast is often a good starting point for replacement, followed by additional eating occasions like morning or afternoon tea, as these are the most studied timings in existing research [6,16,17,25,40,43,44,45]. Other eating occasions may also be appropriate, depending on social, cultural, and lifestyle factors. Ultimately, the choice of when and how to incorporate DSNF should be tailored to individual preferences and guided by health professional advice.

Although DSNF formulations vary in macronutrient composition, fat sources, and fibre type, they share core formulation principles relevant to clinical practice, including low-GI carbohydrate blends, predominantly unsaturated fat sources, and micronutrient profiles designed to support glycaemic management and nutritional adequacy in people with diabetes. Accordingly, this CPG adopts a category-based, product-neutral approach, with selection tailored to individual clinical goals (e.g., glycaemic patterns, weight management, or nutritional support) rather than specific brands or formulations.

3.2.3. Step 3: Monitor Progress

Monitoring of patients using DSNF should tie in with standard best practice guidelines. Baseline attributes should be noted at commencement, and progress should be regularly monitored to allow adaptation of the implementation plan as needed. Monitoring of targets, such as glucose profile including HbA1c, lipid profile including triglycerides and HDL-C, liver function tests, body composition, weight, waist circumference or other targets, should continue as per standard care, with additional early review at 2-4 weeks to assess whether the individual is successfully incorporating the DSNF into their routine.

Evidence from randomised and observational studies suggests that DSNF are generally acceptable to patients and associated with high short- to medium-term adherence. Studies have reported sustained hedonic ratings and compliance exceeding 88–98% across intake levels ranging from one to four servings per day over periods of three to six months [14,19,46]. Several studies have also reported improvements in quality of life following DSNF use over three to six months [23,47,48]. These findings support routine clinical monitoring of acceptability, tolerance, taste fatigue, and patient-reported outcomes when DSNFs are prescribed.

At 3, 6, and 12 months, a broader assessment should be conducted, including (but not limited to) ongoing DSNF use, evaluating glycaemic measures, including markers such as fasting blood glucose and HbA1c, tracking changes in weight and/or waist circumference, assessing body composition where possible, and conducting a medication review. It is important to note that improvements in glycaemic management or weight loss may increase the risk of hypoglycaemia, requiring adjustment of glucose-lowering medication. Achieving clinically significant fat mass loss may necessitate adjustment of their antihypertension medication.

The duration of DSNF use should be guided by the individual’s progress toward their goals. If goals are met, the individual or caregiver and healthcare provider can collaboratively decide whether to continue (maintain, decrease or use intermittent) or pause DSNF use, keeping in mind that the benefits may diminish if use is discontinued, as research data only exists for the duration of use. If goals have not been achieved, it is important to revisit and refine the goals or the way DSNF are being used. If the individual is not already seeing an Accredited Practising Dietitian, referral can be helpful at this point for more tailored support.

Available evidence is largely derived from short-term studies (≤12 months), which have not identified any major safety concerns. DSNF are specifically formulated to meet the nutritional needs of people with diabetes, with nutrient levels within established safety limits. However, data on long-term safety, durability, and maintenance of benefits are limited, highlighting the need for ongoing monitoring, clinical discretion and further long-term research. Importantly, DSNF should always be integrated into a comprehensive diabetes care plan that includes support for adopting a nutritious wholefoods eating pattern, regular physical activity, quality sleep, effective blood glucose and medication management, and regular input from the diabetes care team.

4. Discussion

4.1. Clinical and Practical Implications

This CPG provides a structured, evidence-based framework to support health professionals in integrating DSNF into routine diabetes care. DSNF can be effectively incorporated alongside pharmacotherapy, lifestyle modification, and diabetes education, offering a flexible nutritional option for individuals who are unable to meet dietary goals through wholefoods alone. When used in combination with contemporary agents such as incretin-mimetic therapies and SGLT2 inhibitors, DSNF may enhance glycaemic stability, support weight management, and help preserve lean mass, particularly in older adults or those with frailty. Integration within multidisciplinary care models ensures safe and person-centred implementation. From a system-level perspective, adoption of DSNF is influenced by cost, product access, and cultural relevance. Addressing these factors through clinician education, patient engagement, and potential reimbursement mechanisms will be essential to achieving equitable uptake and sustainable outcomes. While this CPG was developed within the Australian healthcare context, its principles may be relevant to other settings. However, implementation outside Australia may require adaptation to local healthcare systems, resource availability, workforce structures, and cultural practices.

Equity considerations are central to the implementation of this CPG. Access to DSNF and appropriately trained healthcare professionals may be constrained in low-socioeconomic, rural, and remote settings, where availability, cost, and workforce capacity vary substantially [49,50,51]. While DSNFs are generally low-cost nutritional interventions, affordability alone does not ensure equitable access, particularly in settings where supply chains, prescribing pathways, and workforce support are limited. Local adaptation of recommendations for DSNF use will therefore be required to support equitable uptake within existing service structures and resource limitations [50,52]. Future research and implementation efforts should prioritise evaluation of strategies that address these geographic, socioeconomic, and workforce-related barriers, to ensure that the potential benefits of DSNF use are realised across diverse populations [49,51].

4.2. Strengths and Limitations

This CPG is the first of its kind to provide practical, multidisciplinary recommendations for integrating DSNF into routine diabetes care. Developed by a diverse expert working group, including representatives from the ADEA, ADS, and RACGP, the guide is grounded in current evidence, consensus, and real-world clinical experience. The three-step pathway offers clear, actionable guidance for health professionals, supporting person-centred care and consistent implementation across disciplines. The CPG addresses a significant gap in diabetes management by offering solutions for individuals who face barriers to wholefood dietary approaches, and it is designed to be adaptable to a wide range of clinical scenarios and patient needs.

Recommendations in this CPG are product-neutral and based on a category-wide evidence base rather than on specific commercial brands. Evidence supporting DSNF use was drawn from multiple manufacturers and independent studies, including systematic reviews and meta-analyses, to ensure recommendations reflect the category as a whole. Some of the evidence cited originates from meta-analyses commissioned by the Diabetes Nutrition Study Group (DNSG) of the European Association for the Study of Diabetes (EASD) [37], and from recommendations developed by the European Society for Clinical Nutrition and Metabolism (ESPEN) and the DNSG [13]. Importantly, these works were conducted without industry involvement or funding support. In areas where independent comparative data or long-term validation remain limited, recommendations are based on expert consensus and should be applied with clinical judgment. Further independent research will help strengthen future iterations of this guide.

However, a limitation of this CPG is that recommendations are not linked to a formal evidence-grading framework such as GRADE. While the guide draws on the best available evidence and structured expert consensus, the strength and certainty of evidence underpinning individual recommendations are not formally graded. Future updates of this guide will incorporate a formal evidence-grading framework to enhance evidence-based recommendations for clinicians. Also, the majority of studies informing this CPG evaluate short-term outcomes (typically ≤12 months). Evidence on long-term effectiveness, maintenance, and safety beyond one year is limited. While evidence supports the good acceptability, adherence, and short-term quality-of-life improvements associated with DSNF use, most studies are limited to follow-up periods of three to six months and vary in outcome measures and populations. Long-term acceptability, sustainability, and patient-reported outcomes beyond six months remain less well characterised, highlighting an important area for future research. Heterogeneity in DSNF formulations and varying comparators complicate pooled inference and generalisation. Cost-effectiveness, adherence over time, patient-reported outcomes, and equity considerations are under-reported. Although evidence supporting DSNF use is strongest in T2D, data in other diabetes populations are less extensive, representing an important limitation and an area for future research. A further limitation is that this guide was developed within the Australian healthcare system, where funding models, service delivery structures, and workforce roles may differ from those in other countries. As such, recommendations should be interpreted and adapted within local policy and practice contexts when applied internationally.

4.3. Future Research

Pragmatic, longer-term randomised controlled trials and real-world implementation studies evaluating DSNF-augmented care in individuals facing barriers to wholefood nutrition, compared to standard lifestyle care alone, with ≥12–24 month follow-ups are required. Future research should investigate areas including (1) health economic evaluations and equity analyses across diverse populations and settings, building on existing evidence such as the Transcultural Diabetes Nutrition Algorithm; (2) studies with further clinical outcomes (cardiovascular events, microvascular endpoints), body composition (sarcopenia risk, lean mass preservation with incretin-mimetic medications), and durability of outcomes with long-term use; (3) trials examining personalisation parameters (timing relative to glucose excursions, medication class interaction, protein intake targets in older adults/frailty, cultural dietary patterns); and (4) person-centred endpoints including satisfaction, acceptability, dietary quality, food literacy, and transition strategies to sustainable wholefood patterns. Following the dissemination of this CPG, an evaluation will be undertaken alongside a quality improvement program to assess its effectiveness and usefulness in real-world clinical settings and inform future updates.

5. Conclusions

DSNF are scientifically formulated for the nutritional management of people with or at risk of diabetes. DSNF are an evidence-based nutritional supplement that can be a valuable adjunct to standard dietary and lifestyle interventions, particularly when healthy, wholefood-based approaches are not feasible, or not achieving desired health outcomes. With only one in two people with T2D able to follow dietary recommendations, DSNF may provide an additional option when wholefood approaches are not feasible to improve both nutrition and glycaemic outcomes. This approach helps people with or at risk of diabetes meet their nutritional needs, reduce risk of micronutrient deficiencies, improve glycaemia, weight management and body composition, and reduce the risk of long-term complications, including cardiovascular disease. With the aid of this CPG, health professionals will be equipped to better understand the evidence base supporting the use of DSNF and adopt a tailored evidence-based approach to their use in clinical practice.