Low carbohydrate high fat (LCHF) diets are an effective means for people with type 2 diabetes (T2D) to improve glucose control and reduce medication use, however there are still many unanswered questions about the diet. For example, there is much confusion as to what actually constitutes an effective LCHF diet in practice and little is known about the perceptions and experiences of T2D patients who follow an LCHF diet. The physiological mechanisms of how the diet improves glucose control and affects health are not clearly understood. Understanding these mechanisms is important if LCHF diets are to be widely accepted for managing T2D because there are still concerns that the high fat component of the diet will negatively impact other aspects of diabetes pathology.

The burden of diabetes is a growing global problem, not only for patients and families, but also for health insurance providers and the wider economy. Much of this is driven by lifestyle, such as what we eat and drink, smoking and how little we exercise. Health-related behaviour is difficult to shift. Measuring and tracking behaviour in the field is often a challenge. Wearable health-monitoring technology may offer innovative solutions for lifestyle modification, as well as the study of it. We want to understand how we can support type 2 diabetes patients form sustainable low-carb healthy-eating habits. We are motivated by the questions: What level of personalised feedback is most helpful for diabetes patients to achieve their diet and glucose control goals? To what extent do cognitive and behavioural barriers prevent diabetes reversal? This novel study will be relevant in the context of COVID-19 as improved metabolic health is associated with a lower risk of mortality.

Macadamia nuts and its oil contain high levels of monounsaturated fats (MUFAs), namely oleic and palmitoleic acid, as well as phenolic compounds which may provide a beneficial outcome with regards to human biomarkers. A unique relationship exists between the healthful compounds found within macadamia nuts and their capability of interacting with numerous bioenzymatic pathways. This pilot study was conducted with 60 participants to ascertain the effects of consuming macadamia nut oil (MNO) over an 8-week period on various human health markers of interest, mainly relating to changes in hepatic health markers, inflammation, as well as lipid and glycemic profiles. The effects of MNO on the aforementioned human health markers were compared with that of both coconut and olive oil. Participants followed either a low carbohydrate high fat (LCHF) diet (carbohydrates <130 g/d or <26% total energy) or a standard diet (carbohydrates >130g/d or >45% total energy). Participants were randomly assigned one of the three natural oil supplements for the duration of the intervention.

In the LCHF macadamia nut group (LMN), improvements to HDL-C and triglyceride concentrations were observed. Overall, total cholesterol in the LMN increased by 7.36%. Furthermore, GGT, amylase and lipase concentrations bettered. MNO consumption positively affected average fasting glucose concentrations.

The standard diet group (SMN) recorded more improvements than that of the LMN group. CRP levels improved significantly within the group and a positive effect on all hepatic health markers was detected. There was improvement to both LDL-C and triglyceride concentrations. The SMN group followed the same pattern as that of the LMN where fasting glucose levels improved, whilst HbA1c levels negatively increased. Fewer health markers showed improvement in both dietary groups for coconut and olive oil when compared with the MNO groups.

However, improvements to the overall lipid profile of the LCHF coconut oil (LCO) group was observed. Only HDL-C concentrations improved within the standard coconut oil (SCO) group. Markers of inflammation within the LCO group showed improvements, with a significant result for ESR. ESR is a good indicator of inflammation within the body. Average amylase and lipase readings for the SCO group positively decreased. Of the three oil groups, olive oil showed the least improvements to health markers after the intervention. The LCHF olive oil (LOO) group followed the same amylase and lipase pattern as the SCO group, showing a small decline. The olive oils groups were the only ones to show an improvement in HbA1c levels, however, both did not show fasting glucose level improvements. Lastly, both olive oil groups presented a reduction in triglyceride levels.

Macadamia nuts and their unique properties have the potential to lower inflammation and oxidative stress, which may assist in mitigating the risk for chronic diseases. The results of the pilot indicate that including macadamia nut oil into a daily diet may have cardioprotective effects and aid in the prevention of future diseases of lifestyle. From the results obtained in this pilot study, macadamia nut oil demonstrated promising beneficial effects for human health when compared to oils, such as coconut and olive oil. Further research on long-term macadamia nut or macadamia nut oil consumption and its positive effects on certain health markers should be explored in depth.

Study published in the International Journal of Sport Nutrition and Exercise Metabolism provides valuable insights into how nutrient timing can influence athletic performance and recovery. The research examines the effects of consuming specific nutrients at designated times relative to exercise and its impact on performance outcomes.

Key Findings:

1. Optimized Performance: The study demonstrates that athletes who time their nutrient intake around their training sessions experience significant improvements in performance metrics. Specifically, consuming protein and carbohydrates shortly after exercise supports better muscle repair and glycogen replenishment.

2. Enhanced Recovery: Proper timing of nutrient intake, including a combination of proteins, carbohydrates, and fats, plays a crucial role in speeding up recovery. This is essential for athletes who engage in frequent or intense training sessions.

3. Individualized Strategies: The research underscores the importance of tailoring nutrient timing strategies to individual needs. Personalizing nutrient intake based on specific training goals, body composition, and metabolic responses can maximize the benefits of dietary interventions.

Very low-carbohydrate high-fat diets (LCHF, <50 g/day) have been criticized for their potential to lower glycogen stores  and negatively impact endurance performance , particularly during prolonged high-intensity exercise. On the contrary, high-carbohydrate diets (HCLF), rich in glycogen-storing potential, have been considered essential for enhancing performance in endurance sports by preventing early onset of fatigue through sustained carbohydrate (CHO) oxidation. This belief stems from the assumption that muscle glycogen is an obligatory fuel source during prolonged exercise and low-glycogen stores could hasten fatigue.

https://journals.physiology.org/doi/full/10.1152/ajpcell.00583.2024

This comprehensive review challenges the long-standing “crossover concept” in exercise physiology, which posits that fat is the primary fuel at rest and during low-intensity exercise, while carbohydrates become the dominant fuel source at intensities above 60–65% of VO₂max. According to traditional models, fat oxidation is nearly zero at exercise intensities above 85% VO₂max, implying that high-carbohydrate diets are essential for peak athletic performance.

However, the authors present a wealth of

evidence from recent studies—including their own trials on both elite and recreational endurance athletes—demonstrating that athletes adapted to a low-carbohydrate, high-fat (LCHF) ketogenic diet can achieve peak fat oxidation rates of over 1.5 g/min at intensities exceeding 85% VO₂max. These findings substantially revise the traditional understanding of fuel use during high-intensity exercise. The review shows that the crossover point can shift significantly when athletes follow an LCHF diet, enabling fat to remain a major energy source even at high exercise intensities.

In addition to performance implications, the study discusses the metabolic health benefits of the LCHF diet. A notable finding is that 30% of middle-aged, lean endurance athletes exhibited pre-diabetic blood glucose levels while consuming a high-carbohydrate diet—an issue that resolved entirely upon transitioning to the LCHF diet. These improvements in glucose regulation were independent of body composition, activity levels, or caloric intake, pointing strongly to dietary composition—specifically reduced carbohydrate and insulin load—as the key driver.

The review also explores how the LCHF diet enhances mitochondrial efficiency and fat oxidation by lowering insulin levels and increasing free fatty acid availability. These metabolic adaptations contribute to improved glycemic control and support high-intensity

performance, countering the long-held belief that carbohydrates are obligatory for such efforts.

In summary, the article presents compelling evidence that the crossover concept does not apply uniformly across dietary contexts. LCHF-adapted athletes not only maintain performance at high intensities but also experience enhanced fat metabolism and better glycemic control. These insights suggest that dietary strategies have significant potential not only for athletic performance but also for reducing the risk of metabolic disease—even in seemingly healthy, active individuals.

This randomized, crossover-controlled study examined the effects of low-carbohydrate, high-fat (LCHF) versus high-carbohydrate, low-fat (HCLF) isocaloric diets on endurance performance, fat oxidation, glycemic control, and cardiometabolic health in middle-aged, competitive male athletes. Over two 31-day dietary periods, participants followed either an LCHF or HCLF diet while maintaining consistent caloric intake and training loads. Researchers assessed athletic performance, continuous glucose monitoring (CGM) data, substrate oxidation during exercise, and a range of metabolic biomarkers.

The study found no difference in high-intensity exercise performance between the two diets, despite a significant shift in energy substrate utilization. The LCHF diet led to record-high rates of fat oxidation during exercise—peaking at 1.58 g/min, with 30% of participants exceeding 1.85 g/min—far surpassing previously documented rates. This shift was accompanied by significant reductions in mean and median blood glucose, glucose variability, and markers of glycemic instability. Notably, 30% of participants had pre-diabetic glucose values while on the HCLF diet, all of which normalized under LCHF. These same individuals also experienced the largest improvements in fat oxidation and glycemic control, suggesting a strong relationship between metabolic flexibility and dietary carbohydrate restriction.

The LCHF diet was also associated with higher total, LDL, and HDL cholesterol, but without negative changes in other cardiometabolic markers such as fasting insulin, hsCRP, or HbA1c. Body composition remained stable across both dietary phases, indicating that observed health and metabolic improvements were independent of weight loss.

Overall, the study challenges the long-held belief that high-carbohydrate diets are essential for high-intensity endurance

performance. Instead, it demonstrates that, after an appropriate adaptation period, an LCHF diet can support equivalent performance while offering significant improvements in fat metabolism and glycemic control. These findings have important implications not only for athletic populations seeking metabolic efficiency but also for broader public health strategies targeting insulin resistance and pre-diabetes in active middle-aged adults.