Glycolysis

Glycolysis is the metabolic pathway that converts glucose to lactic acid, yielding a small amount of usable energy—many times less than mitochondrial oxidative phosphorylation provides. 2 Peat distinguished between anaerobic glycolysis, a normal response to insufficient oxygen during intense muscle action, and aerobic glycolysis (the Warburg effect), the pathological conversion of glucose to lactic acid even in the presence of adequate oxygen, as seen in cancer, shock, and extreme trauma. 3 The presence of oxygen normally restrains glycolysis so that glucose is oxidized to carbon dioxide; when this restraint fails, the cell reverts to a more primitive form of energy production that supports only cell division and primitive function, not the complex differentiation supported by respiration. 1

Peat argued that the products of glycolysis, lactic acid and pyruvic acid, are not merely markers of respiratory failure but are themselves toxins that suppress mitochondrial respiration, creating a vicious cycle. 2 Lactic acid is associated with calcium uptake, nitric oxide production, and energy depletion, contributing to cell death and the systemic derangements of hyperventilation, including vascular leakiness, brain swelling, and multiple organ failure. 3 He identified the Crabtree effect—the inhibition of cellular respiration by an excess of glucose—as a general stress phenomenon in which glycolysis is activated while oxidative metabolism is shut down, a maladaptive response given respiration's far greater efficiency. 2 This is distinct from the normal Pasteur effect, where respiration limits glycolysis to the rate at which its products can be oxidatively consumed. 2

The regulation of glycolysis is tightly coupled to carbon dioxide and the systemic metabolic state. Peat explained that a high background of carbon dioxide promotes circulation and oxygenation, preventing the anaerobic glycolysis that produces toxic lactic acid. 2 Conversely, when carbon dioxide is deficient, aerobic glycolysis is favored, and the resulting lactate suppresses glucose oxidation while increasing the oxidation of fats, further lowering metabolic efficiency through the Randle effect. 2 Peat noted that glycolysis, as the initial splitting of glucose to pyruvate, is a normal part of oxidative metabolism and is preferable to burning excessive fat, provided the pyruvate enters the Krebs cycle rather than being reduced to lactate. 11 Dinkov has extended this framing, describing cancer as a reversal to a primitive state of metabolism where cells rely exclusively on glycolysis, producing very little ATP and large amounts of lactic acid, leading to structural degradation and uncontrolled growth. 10

Peat traced the conceptual history of glycolysis through the work of Warburg and Szent-Gyorgyi, who viewed it as a primitive energy system, and emphasized that the organized, enzyme-to-enzyme handoff of substrates within the cell challenges the dilute-solution assumptions of classical biochemistry. 2 He identified several factors that suppress glycolysis and promote oxidative metabolism, including thyroid hormone, palmitic acid, light, and vitamin B1, while estrogen, unsaturated oils, and phytoestrogens promote the glycolytic stress state by increasing free fatty acids and inhibiting thyroid function. 2 Roddy notes that Peat's focus on glycolysis often centers on the recycling of carbon units and the critical role of mitochondrial carbon dioxide output in determining whether the link reaction proceeds, rather than on the textbook depiction of glycolysis as merely the first step in glucose oxidation. 2