A small University of Cape Town observational study, led by Dr Tim Noakes, found that “type 2 diabetes (T2D) is reversible by restricting daily carbohydrate intake to less than 25g/day”.
Until recently, low carbohydrate high fat (LCHF) diets were not supported by most type 2 diabetes (T2D) dietary guidelines, and the high fat component of these diets is still controversial due to concerns over long-term health outcomes. Despite this, there are a growing number of individuals following their own version of an LCHF diet to manage their T2D. The aim of this study by researchers at the division of exercise science and sports medicine, University of Cape Town, South Africa was to characterise the diets, health, and personal experiences of individuals with T2D who claimed to have followed an LCHF diet for at least the previous 6 months. A total of 28 participants completed the study and 24 of these participants were assessed for a second time after 15 months.
According to Noakes, the study shows that TD2 is a reversible condition “if patients will simply restrict their daily carbohydrate intake to less than 25g/day”.
“Perhaps the key finding is that the low carbohydrate diet has a unique ability to remove food cravings/addictions without which it is likely that long-term ‘reversal’ of type 2 diabetes will not happen,” said Noakes.
Previous claims by Noakes and around the LCHF diet have been controversial. See below for related articles.
Background: Low carbohydrate high fat (LCHF) diets are increasing in popularity amongst patients with type 2 diabetes (T2D), however it is unclear what constitutes a sustainable LCHF diet in a real-world setting.
Methods: This descriptive multi-method study characterized the diets, T2D status, and personal experiences of individuals with T2D who claimed to have followed an LCHF diet for at least 6 months. Participants completed a medications history, mixed-method dietary assessment, provided a blood sample, and were interviewed in-depth about their experiences with the diet (First-Assessment). Past medical records were obtained corresponding to T2D diagnosis and prior to starting their LCHF diets. Additionally, participants were followed up 15 months later to assess T2D remission (Follow-Up).
Results: Twenty-eight participants completed First-Assessment and 24 completed Follow-Up. Habitual carbohydrate intake was 20 to 50 g/d for 10 participants and 50 to 115 g/d for 17 participants. Commonly reported foods were full-fat dairy, non-starchy vegetables, coconut oil, eggs, nuts, olives and avocados, olive oil, and red meat and poultry with fat. Median (interquartile range) for HbA1c was 7.5 (6.5–9.5) % prior to starting their diets, 5.8 (5.4–6.2) % at First-Assessment and 5.9 (5.3–6.6) % at Follow-Up. Reported body weight and glucose-lowering medication requirements were considerably lower at both assessments than when starting the diet. At Follow-Up, 24 participants had been following their LCHF diets for 35 (26–53) months, the majority of which were in full or partial T2D remission. Participants perceived reduced hunger and cravings as one of the most important aspects of their diets. Of concern, many participants felt unsupported by their doctors.
Conclusion: This study described the foods and characteristics of an LCHF “lifestyle” that was sustainable and effective for certain T2D patients in a real-world setting.
Christopher C Webster, Tamzyn E Murphy, Kate M Larmuth, Timothy D Noakes, James A Smith