Almost 100 years ago, Otto Warburg discovered the altered cellular metabolism of cancer cells: switching from oxidative phosphorylation to aerobic glycolysis (Warburg effect). Although quiet for many years, the field of cancer metabolism has experienced a revolution in the last decade. Now recognised as one of the hallmarks of cancer, the metabolism field is rapidly evolving and expanding to unveil new pathways and molecular mechanisms beyond the Warburg effect; changes in the metabolism of sugars, lipids, amino acids and other sources of energy are now investigated as part of the phenomenon of metabolic rewiring in cancer. As a result, new therapeutic approaches targeting cellular metabolism are being tested with varied success for different cancer types, expanding the range of current treatment options.