Summary
Highlights
The body functions like a city with mitochondria as power plants. Different fuel sources (glucose, fat, protein) act as traffic. The Randle cycle explains that cells prioritize fuels based on availability rather than excluding one entirely.
Alcohol serves as an emergency vehicle in our traffic analogy. Because the body treats it as a priority for clearance, fat burning is temporarily paused. This is a safety feature of the liver, not a metabolic failure.
A healthy metabolism can efficiently switch between fuel sources. Metabolic inflexibility occurs when the system remains permanently blocked. True health is defined by the ability to transition smoothly between fuels.
To improve metabolic flexibility, one should focus on movement, building muscle, getting adequate sleep, managing stress, and allowing significant time between meals to let the 'traffic' clear.