Jodie Webber, ANutr, Kai Sento Kargbo, BA, and Shane McAuliffe, RD
AcknowledgmentsThank you to the panel and presenters for sharing their time, insights, and experiences.
Dr Michele Vacca, Dr David Unwin, Dr Kathy Martyn, and James Bradfield (RD)
Journal Club Presenters/Panel
Prof Sumantra Ray, Shane McAuliffe (RD), Dr Rajna Golubic, Elaine Macaninch (RD), and James Bradfield (RD)
In January 2021, IANE held the first webinar of the year: Macronutrient Modulated Diets - Focus on Carbohydrates, Type-2 Diabetes, and Non-Alcoholic Fatty Liver. In February, the accompanying Journal Club session was held, where the topic was discussed further, with reference to the recent position statement published by Diabetes Canada (2020). Here, the main ideas from the webinar and the journal club sessions will be summarised, but please remember the full recordings of both sessions can be accessed on the IANE webpage here.
Our first speaker, Dr. David Unwin discussed a recent audit conducted with colleagues at his GP surgery in the UK on a low carbohydrate diet (LCD) in patients with Type 2 diabetes mellitus (T2DM) and prediabetes (Unwin et al. 2020). This audit involved 127 patients with T2DM and 71 with prediabetes, which accounted for 27% of the total T2DM population for the practice. Patients were advised on the LCD approach and were informed on how their dietary choices impact their glycaemic control. Further, progress graphs and/or reports were shared with patients throughout. Key findings from this audit include:
Reductions in overall weight and HbA1c levels in patients with T2DM, and HbA1c reduction in patients with pre-diabetes.
Drug-free remission in 46% of patients with T2DM.
93% of the pre-diabetic group achieved normal HbA1c levels.
An overall reduction in total cholesterol, increased HDL cholesterol, reduced triglycerides, reduced weight, improved blood pressure, and improved liver function.
The LCD approach was successful with both older patients and young adult patients.
The practice calculated that they made a saving of £50,885 over the year. Dr. Unwin reiterated the importance of feedback to behaviour change, however, there was a range of possible confounding factors that could not be controlled for and no control group for comparison. It is also important to acknowledge that more than two-thirds of the practice T2DM population did not follow the LCD advice, meaning a large proportion remains to be considered and catered for, requiring a focus on alternative dietary approaches to meet their needs. The need for more robust studies that account for these factors was reiterated, as well as the importance of evidence-based medicine that includes the best scientific evidence, clinical experience, and places patient values at the core.
Dr. Michele Vacca then joined us to provide a ‘deep dive’ into the science of carbohydrates and metabolic syndrome. Dr. Vacca explored the role of glycaemic index and the timing of eating (chrononutrition) as important factors, alongside carbohydrate quantity. Drawing upon a paper with colleagues (Salvia et al. 2017), his study of a calorically unrestricted but carbohydrate-moderated Mediterranean diet was discussed. Dr. Vacca and colleagues found that reductions in glycaemic index and carbohydrate intake, particularly in the evening, resulted in weight reductions and improved glycaemia and dyslipidemia in patients with metabolic syndrome.
Our third speaker, James Bradfield (RD), shared his experiences from academic research and his work as an NHS dietitian. He discussed the popularity of LCDs in the context of increasing levels of overweight, obesity, and T2DM, and the overlap between them. In summing up the evidence, many important points were addressed:
There is no universally accepted definition of an LCD; the term is relative.
LCDs often do not emphasise what a person is eating, only what they are not eating.
Healthcare practitioners must consider the cultural appropriateness and affordability of LCDs when making recommendations, whilst also being conscious of the language used to share nutrition information, particularly on social media.
Some investigation should be made into the environmental impact of LCDs, and how they can be shaped to be more environmentally friendly.
There is no ‘one size fits all' approach with diet; whilst LCDs work for some patients, they won’t work for others, and patients must be involved in the decision-making.
Lastly, we heard from Dr. Kathy Martyn who spoke on ‘Balancing Science and Practice’ and provided us with a summary of the webinar. Dr. Martyn shared a fascinating history of diabetes and the developments in approaches to treatment, from starvation diets, carbohydrate counting, to medications and LCDs. She concluded by reiterating the importance of a continuous cycle of science and evidence-based practice, and the role of scientists and practitioners in implementing, evaluating, and improving their approaches.
This webinar session reminded us of the importance of considering all macronutrients, not just one, as well as the central role of science in providing an understanding of the metabolic pathways involved with diabetes and metabolic syndrome. Reechoing Dr. Unwin’s mention of ‘hope’; we must focus on patient-centred practice that allows the spread of hope and autonomy.
Journal Club Presentation
Professor Sumantra Ray introduced the journal club and reminded us of the key points raised in the webinar. We then heard from Shane McAuliffe (RD) who presented a critical appraisal of the position statement published by Diabetes Canada (2020). The statement makes it clear that an individualised approach is important, and that an LCD approach can be subjective, depending on an individual’s baseline carbohydrate intake, meaning what is defined as ‘low’ for one person may be very different for another. Some of the key research findings in both Type 1 Diabetes (T1DM), and T2DM were discussed, and we learned that there is very limited long-term evidence for both. When considering LCDs and T1DM, the research often lacks depth, whereas in studies of T2DM, there are promising findings regarding reductions of medications, but methodological concerns are present. Our attention was drawn to some of the questions and uncertainties surrounding this research, including the longer-term sustainability of LCDs and many confounding factors, such as caloric intake and weight loss. As a result, whilst LCDs may present a real therapeutic option to healthcare providers and patients, further research is essential, and patients must be at the centre of any decision-making.
Finally, before the open discussion, we heard from Dr. Rajna Golubic who presented a medical perspective with her presentation ‘Questions in Low Carbohydrate Diet yet to be Answered in Clinical Practice’. Dr. Golubic discussed the current evidence around low carbohydrate diets in clinical practice. Some of the main points raised were that the short-term use of LCDs may be considered as a management approach for T2DM, but that ‘active monitoring’ is essential, along with consideration of the necessary adjustments to patients’ diabetes medication. Dr. Golubic also shared thoughts on the many unanswered questions that remain, such as the interactions with physical activity and medications, the effects on disease endpoints, effects on the microbiome and metabolome, and the possibilities of genetic variants which may lead to some individuals having differential responses to such diets. Again, the overarching conclusion was that well-designed trials are the necessary next step in answering these questions.
The open discussion stimulated a range of questions and comments, and some of the contributions from the panel are noted here.
Accessibility was a recurring theme. Elaine Macaninch (RD) shared her experiences of working with patients with gestational diabetes and emphasised the importance of rethinking the process to allow consideration of where nutrition can fit in, in order to give patients, the opportunity to try dietary change approaches before medication. Central to this conversation was the importance of being understanding and compassionate towards individuals’ personal circumstances, beliefs, and motivations. This aligns with points raised about affordability and the fact that shifting dietary patterns requires shifts in purchasing patterns. Additionally, healthcare providers must work with their patients in order to ensure that dietary change recommendations are feasible, sustainable, and appropriate. We were left with the important reminder that dietary choice, and in particular, choosing to omit certain foods from our diets, comes from an inherent place of privilege.
The question of 'Whether a more drastic reduction is better?’ was raised with regards to the perception of LCDs. The panel discussed whether knowledge that LCDs could offer positive therapeutic effects could lead to the belief that very low carbohydrate diets, or ketogenic diets, are more beneficial. The notion of an individualised approach was revisited, and there was agreement that it is important to focus on what is right for the individual patient, their knowledge, and their motivations. For instance, for those patients where adherence to an LCD is particularly challenging, the ketogenic diet would likely be unsustainable. This linked to discussions on social media platforms and press coverage. Although these platforms offer an environment for sharing tips, meals, and experiences, they can also be used to misrepresent the reality of these diets. Individuals may find a dietary ‘label’ attractive because it provides the opportunity to be a part of something, but it is important that patients make these decisions with a focus on changing habits and understanding the full story.
Key Take-Home Points
LCDs present a valid therapeutic option for some patients, but further research is essential to explore the many unanswered questions that remain.
Patients must be supported by their healthcare providers to fully understand their options, and they should be at the centre of decision-making about their own health.
Healthcare providers should focus on how to communicate options effectively, including sharing information about the physiology of disease in an understandable and accessible manner. This will equip patients to make the best decisions for their personal circumstances.
Accessibility, affordability, and cultural context play central roles in dietary choice and change; the context must be considered.
The perception of LCDs amongst patients should be considered, alongside patients’ personal motivations and beliefs around their health, nutrition, and therapeutic options.
The next IANE webinar will be held on 24th March 2021, focusing on ‘Diet and Climate Change’. See https://iane.nnedpro.org.uk/Events for further information.
Diabetes Canada (2020). Diabetes Canada Position Statement on Low-Carbohydrate Diets for Adults With Diabetes: A Rapid Review. Canadian Journal of Diabetes, 44, 295-299.
Salvia R, D'Amore S, Graziano G, Capobianco C, Sangineto M, Paparella D, de Bonfils P, Palasciano G, Vacca M. (2017). Short-term benefits of an unrestricted-calorie traditional Mediterranean diet, modified with reduced consumption of carbohydrates at evening, in overweight-obese patients. International Journal of Food Sciences and Nutrition, 68(2), 234-248.
Unwin, D., Khalid, A., Unwin, J., Crocombe, D., Delon, C., Martyn, K., Golubic, R., Ray, S. (2020). Insights from a general practice service evaluation supporting a lower carbohydrate diet in patients with type 2 diabetes mellitus and prediabetes: a secondary analysis of routine clinic data including HbA1c, weight and prescribing over 6 years. BMJ Nutrition, Prevention & Health, 3, 285-294.