Warburg effect

The Warburg effect is the observation by Otto Warburg that cancer cells exhibit aerobic glycolysis—the persistent conversion of glucose to lactic acid even in the presence of adequate oxygen—due to a respiratory defect in their mitochondria. 3 Peat emphasized that this is not evidence that sugar causes cancer; rather, the impaired mitochondrial respiration forces the cell to rely on glycolysis, and the cancer will instead burn the body's protein and fat stores if sugar is withheld. 2 Warburg himself demonstrated that prolonged oxygen deprivation could cause normal cells to become cancerous, and Peat argued that the cancer's rapid consumption of glucose and oxygen exceeds the capacity of the blood supply, creating a hypoglycemic and hypoxic local environment. 7

The metabolic shift is characterized by a failure of the Pasteur effect, where oxygen normally suppresses lactic acid formation. 2 Peat noted that the instantaneous effect of either estrogen or unsaturated fatty acids is to imitate the Warburg effect by promoting lactic acid production and blocking oxidative energy use. 2 Dinkov has written that a drop in the NAD to NADH ratio, caused by inflammatory unsaturated fats or estrogen, can trigger this malfunction by impairing enzymes like pyruvate dehydrogenase, and that the Warburg effect is not merely a consequence but also a cause of further metabolic disruption. 6 The resulting lactic acid creates a reduced cellular state that Peat identified as initiating all the electronic and energetic properties of cancer, with lactic acidemia preceding genomic abnormalities. 9

A central feature of the Warburg effect is that the cancer cell's interior becomes more alkaline as lactic acid is exported, which blocks oxidative metabolism and perpetuates a vicious cycle of inefficient energy production. 3 Peat explained that a slightly acidic intracellular pH of 6.8 is metabolically efficient, and that lowering the pH suppresses lactic acid formation, imitating the action of thyroid hormone. 3 This contrasts sharply with normal oxidative phosphorylation, which produces carbon dioxide and promotes a self-healing internal environment, whereas the lactic acid produced by the Warburg effect activates stress systems, promotes lipolysis, and suppresses immunity. 2 The excitatory amino acid glutamate, increased by lactate, drives cellular calcium uptake, and Dinkov has pointed to evidence that the intracellular accumulation of calcium beyond a certain level directly leads to aerobic glycolysis. 2

Peat viewed the Warburg effect as an accurate picture of cancer's physiological nature, where the cell's inability to turn off energy expenditure drives inflammation, angiogenesis, and metastasis. 2 He considered the Randle cycle—the inhibition of glucose oxidation by an excess of fatty acids—as a key contributor, where fat oxidation lowers CO2 production and increases lactate, creating a wasting process that consumes the body's fat and protein stores. 2 Dinkov has extended this by noting that oxidizing stored polyunsaturated fat is particularly harmful because it generates an inflammatory, estrogenic effect that further drops the NAD to NADH ratio and suppresses oxidative phosphorylation. 6 Peat argued that increasing glucose can protect against this excitatory damage by enabling cells to extrude calcium, shifting metabolism back toward carbon dioxide production. 7