How metabolism creates energy

Every heartbeat, every thought, every breath is paid for in a single molecule, made, and spent, billions of times a second inside your cells.

Metabolism can sound abstract, but at its core it is about one practical thing: turning food into usable energy. And nearly all of that energy is carried by a single molecule, adenosine triphosphate, ATP.

The cell's power plants

The work happens largely inside mitochondria, often called the powerhouses of the cell, whose job is to keep up a steady supply of ATP.¹ Under normal conditions, mitochondrial oxidation provides more than 90% of a cell's ATP.²

Food in, energy out, through one molecule, made billions of times a second.

From sugar to energy

The process unfolds in stages. First, in glycolysis, glucose is broken down into a molecule called pyruvate, yielding a small amount of ATP. The pyruvate then enters the mitochondrion and passes through the citric acid cycle. Finally, in oxidative phosphorylation, a flow of protons across the mitochondrial membrane drives an enzyme, ATP synthase, to assemble ATP from ADP¹, the step that produces the great majority of the cell's energy.

Why it matters for health

When this machinery runs well, tissues that demand enormous amounts of energy (the heart, the brain, the muscles) are kept supplied. When it falters, the effects ripple across the very organs that can least afford an energy shortfall, which is one reason metabolism sits so close to the centre of cardiometabolic health.