Far more than 700 enzymes in the body

“More than 700” is not a reliable modern estimate of the total number of human enzymes. It may reflect older counts of individually described enzymes, but the human genome encodes thousands of enzyme proteins, and protein isoforms and tissue specificity complicate counting. The Human Protein Atlas classifies thousands of proteins in enzyme groups, although totals depend on classification criteria. A safer statement is that the body uses a large and diverse enzyme system, without presenting 700 as a definitive count.