Peat Archive

In Ray Peat's framework, lactic acid is one of the key markers of metabolic failure. While mainstream physiology treats lactate as a normal byproduct of exercise, Peat argued that chronic lactic acid production (even at rest) indicates that cells are relying on glycolysis rather than efficient mitochondrial respiration. This shift — from CO2-producing oxidative metabolism to lactate-producing glycolysis — is the essence of the Warburg effect in cancer and a hallmark of aging and stress.

Peat noted that lactic acid has the opposite physiological effects of carbon dioxide: it promotes inflammation, edema, calcium dysregulation, and tissue damage. Elevated lactate in the blood indicates that thyroid function, nutrition, or mitochondrial integrity are compromised, and addressing these root causes is essential.