What diet do people with type 2 diabetes really want? Study reveals flexibility beats strict meal plans

British adults with diabetes overwhelmingly favor simple, adaptable eating patterns over rigid low-calorie meal replacements, highlighting that personal choice may be key to long-term adherence and better health outcomes.

Study: Understanding Preferences for Weight Loss Diets Amongst Patients With a Diagnosis of Type 2 Diabetes. Image Credit: Anton Vierietin / Shutterstock

In a recent article published in the Journal of Human Nutrition and Dietetics, researchers investigated the dietary approaches preferred by British adults with type 2 diabetes (T2D) and the reasons behind these preferences. They found that most participants preferred moderately calorie-restricted or low-carbohydrate food-based diets, prioritizing ease of following instructions and simplicity as the most important qualities of an adequate diet.

Relationship Between Type 2 Diabetes and Dietary Management

T2D is closely linked with obesity and overweight, and dietary weight loss remains central to its management. However, many individuals struggle to adhere to prescribed diets due to barriers such as cultural food practices, social routines, and complex diet structures.

Current UK Recommendations for Low Energy Diets

In the UK, CLEDs, which use formula-based meal replacements (800–900 kcal/day for 12 weeks), are recommended for adults with overweight or obesity and who are within six years of diagnosis to achieve diabetes remission. While CLEDs have demonstrated substantial weight loss and glycemic improvement in clinical trials, program uptake and completion rates remain low due to social and practical challenges.

Intermittent Low-Energy Diets as an Alternative

As an alternative, ILEDs involve two low-calorie days per week and normal healthy eating on other days, offering greater flexibility and potentially better adherence. Previous studies have shown that ILEDs can achieve comparable weight and blood sugar improvements to CLEDs, although the present survey did not directly measure these outcomes.

Importance of Autonomy and Choice in Diet Adherence

Considering individual lifestyle needs and the psychological benefits of autonomy, offering dietary choice may enhance motivation and adherence. Guided by self-determination theory, this study aimed to explore which diet individuals with T2D prefer, whether CLED, ILED, or other calorie-restricted approaches, and to understand the reasons underlying these preferences to support more personalized, patient-centered dietary advice.

Survey Design and Participant Recruitment

A cross-sectional online survey was conducted among adults with T2D who had previously attempted dietary weight management. Participants (n = 622) were recruited via the NHS volunteer databases, social media platforms, and the Prolific research register.

Role of Patient and Public Involvement in Survey Development

The survey was co-developed with a PPIE group of individuals with T2D, who identified key factors influencing diet choice: medication reduction, health improvement, speed of weight loss, blood sugar control, food flexibility, simplicity, social compatibility, and professional support.

Survey Structure and Analytical Methods

The final 16-question survey collected demographic, health, and treatment details and asked participants to rate the importance of these factors when choosing a diet. Participants were given short descriptions of CLED and ILED and asked to state which they preferred and why. They also indicated their preference among four diet types (CLED, ILED, moderate calorie-restricted, or low-carbohydrate) and provided qualitative explanations. A three-step binary logistic regression model was used to identify predictors of preference between CLED and ILED, controlling for demographic, health, and lifestyle factors. Free-text responses were analyzed using content analysis guided by predefined categories from the PPIE group.

Participant Demographics and Health Profiles

Participants were predominantly female (59%), Caucasian (88%), and had a median age of 55 years. Most were overweight or obese (88%) and reported annual household incomes below £40,000. The average duration of diabetes was about 11 years, with most managing it through tablets or a combination of diet and tablets.

Predictors of Dietary Preference: CLED vs ILED

When comparing CLED and ILED, 57% preferred ILED. Logistic regression identified ten significant predictors of preference. Younger participants (those under 65) were more likely to prefer CLED, while older adults (75 and above) favored ILED. Those prioritizing rapid weight loss or reduced medication dependence tended to prefer CLED, whereas individuals valuing flexibility, social meal compatibility, and ease of adherence preferred ILED. Health and treatment variables did not independently predict diet choice, although they contributed to the overall model.

Broader Dietary Preferences Beyond Low Energy Diets

When additional dietary options were offered, 36.5% favored a moderate calorie-restricted diet and 29% preferred a low-carbohydrate diet, compared with 17.7% for CLED and 12.4% for ILED. Content analysis showed that simplicity, flexibility, and personal fit were the most frequently cited reasons for diet choice, while other influential factors included financial considerations, prior diet experiences, and managing comorbidities.

Influence of Age and Lifestyle Fit on Diet Choice

This large-scale survey found that diet preferences among individuals with T2D varied according to age, goals, and lifestyle fit. Younger participants favored CLED for its rapid results and structured format, while older individuals preferred ILED for its flexibility and social compatibility, particularly the ability to share meals with their family.

Implications for Personalized Nutrition and Diabetes Management

Preferences for moderate calorie-restricted and low-carbohydrate diets surpassed both CLED and ILED, emphasizing the importance of dietary autonomy and ease of adherence. These findings align with prior research showing comparable clinical benefits between CLED and ILED but differing acceptability and sustainability.

Strengths, Limitations, and Future Research Directions

A major strength was the involvement of a PPIE group, ensuring relevance and clarity of the survey. Limitations included limited ethnic diversity, reliance on self-reported data, and the absence of clinically verified glycated hemoglobin (HbA1c) data. Because this was a cross-sectional study, causal relationships between preferences and participant characteristics cannot be inferred. Future studies should verify glycemic data, assess the impact of matching diet types to patient preferences, and investigate the role of cultural influences.

Overall, these results highlight the importance of individualized and patient-centered dietary advice that can enhance long-term adherence and health outcomes.