AST/ALT ratio (De Ritis ratio)

The AST/ALT ratio (also called the De Ritis ratio, after Fernando De Ritis, who described it in the 1950s) is just one liver enzyme divided by another: AST divided by ALT. In ordinary liver-cell injury, ALT rises more than AST (it is more liver-specific), so the ratio drops below 1.0. In alcoholic liver disease, the ratio usually climbs above 2.0. That is partly because alcohol depletes a vitamin (pyridoxal phosphate) that ALT needs, and partly because damaged mitochondria spill AST. A ratio above 1.0 with raised enzymes also hints at cirrhosis, where regenerating nodules lose ALT first. Beyond the liver, a high ratio when the absolute enzymes look normal can reflect AST coming from your skeletal or heart muscle instead. In longevity research, a ratio that stays above about 1.0 (without acute illness or hard exercise) is tied to higher cardiometabolic risk and death. So it is worth investigating for alcohol injury, fatty-liver inflammation, or hidden cirrhosis, not brushing off.

Last reviewed: June 22, 2026

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