Cancer can be attacked directly by metabolic enzymes and then be assisted by the enzyme diet programme. The second greatest cancer breakthrough of the 20th century is the metabolic organic effect on malignant tumours of correcting the body fluid pH to a non-acidic pH 7.1 to 7.5. A neutral pH 7.0 resists cancer formation. An acid body fluid pH of 6.44 and below permits tumours to biochemically become malignant. At pH 7.5 cancer may become inactive; at 8.5 tumours may disintegrate.