Ketone Levels

Ketone readings above 2.0 mmol/L are uncommon even during extended fasting or fat-only eating. Blood ketone numbers alone are an incomplete picture of a person's metabolic status. Blood ketone readings that are initially high will naturally decrease over time on a ketogenic diet due to fat adaptation, and this decline is not a sign of failure. Early elevated ketone readings reflect the mitochondria's lack of capacity to efficiently utilize ketones, not a peak metabolic state. Treating ever-higher ketone readings as the primary success metric of a ketogenic diet misses the underlying biology of what those numbers represent.