Updated 6 October 2026. Based on my first-author systematic review and meta-analysis, published in the European Journal of Nutrition in January 2026. Read the original paper.
The question behind my research
Our review compared energy-matched lower-carbohydrate diets (44% or less of total energy) with higher-carbohydrate diets (45% or more) in healthy, non-medicated adults. It included 18 randomised controlled trials and 905 participants.
What we found
Lower-carbohydrate diets had modest pooled advantages for fasting glucose, insulin, triglycerides and HDL cholesterol. They also produced somewhat greater reductions in body weight and fat mass. Higher-carbohydrate diets produced a greater reduction in LDL cholesterol. There was no significant between-diet effect on total cholesterol or fat-free mass.
These results concern selected biomarkers and body-composition outcomes, not proof that either approach prevents disease. Participants were not recruited as a diabetes-treatment population. The lower-carbohydrate category was broad and was not synonymous with a ketogenic diet.
Why the trade-off matters
The findings support individual decisions, rather than declaring one diet superior on every outcome. Energy matching improves the comparison, but replacing carbohydrate also changes other parts of the diet. It does not identify carbohydrate alone as the mechanism responsible for every difference.
How I translate that into coaching
A useful nutrition plan begins with the person in front of me. I want to understand your goals, training, current meals, food preferences and the practical limits of your week. A diet that sounds ideal but repeatedly falls apart is a poor starting point for lasting progress.
For one client, the main issue might be long gaps between meals followed by unplanned evening eating. For another, it might be a meal plan that is difficult to maintain around family life. Those problems need practical solutions before debating small differences in carbohydrate percentage.
I would agree what we are trying to improve, choose measures that are relevant, and review the pattern over time. Training performance, how you feel, your ability to follow the plan and appropriate body-composition measures can all inform the conversation. Where blood results or a diagnosed condition need interpretation or treatment, I work within the appropriate professional boundaries and encourage clinical input.
What this study does not justify
I would not turn it into a promise to reverse diabetes, normalise hormones or make saturated fat harmless. Nor would I tell every athlete to avoid carbohydrates. Those are broader claims that require their own evidence and individual assessment.
Nutrition research is useful precisely because it lets us ask better questions. Which outcome matters? Does the study population resemble you? What did the comparison diet actually contain? What is the size of the difference, and would it change the decision you make?
A practical first step
Keep a short, representative record of your usual meals, training and schedule. Include busy days and weekends rather than presenting an artificially perfect week. Then identify the changes you are most likely to sustain.
My coaching aims to turn evidence into a workable routine, with adjustments based on your response. There is no requirement to follow one dietary label or purchase supplements to work with me. Tell me about your goals to discuss suitable support.
Original publication
Anagnostou A, Larumbe-Zabala E, Fiore J, Roberts J, Naclerio F. Effects of energy-matched low- versus high-carbohydrate diets on glycaemic control, lipid profile, and body composition in healthy adults: a systematic review and meta-analysis of randomised controlled trials. European Journal of Nutrition 65, 19 (2026). doi:10.1007/s00394-025-03862-z.