There are dozens of different cancers: some are more serious than others but all of them are to be avoided if we can. There are also many possible causes including smoking, air pollution, and a wide variety of toxic chemicals used in the manufacture of everyday items. For many years, people have thought cancers were driven by genetic mutations but evidence is growing that cancer is a metabolic disease. The toxic substance that disrupts our metabolism the most is sugar.
A German doctor, Otto Warburg, discovered that cancer cells use a different energy metabolism compared to healthy cells. He won a Nobel prize for his work in 1931. He found that malignant tumors rely entirely on glucose as a source of energy, while healthy cells can use fat molecules instead. Cancer cells use glucose at 10 to 12 times the rate of normal cells and Warburg suggested that cancer might be starved of energy by reducing sugar intake. It is important to remember that all carbohydrates, when digested, become sugar molecules.
Whenever blood sugar levels rise, the pancreas produces insulin to lower them. Insulin, however, does a lot more than this. It is a master hormone with many effects in the body, including the stimulation of cell growth. A tumour is a mass of rapidly dividing, and growing, cells: an excess of sugar will feed those cells and the inevitable increase in insulin will stimulate their growth. Breast cancer, which is one of the most common types, has been linked to sugar intake. Breast tissue contains a lot of insulin receptors.
Obesity is known to be associated with a large increase in the risk of cancer. People become obese because they eat too much carbohydrate, and sugar, which is stored as fat by the hormone insulin. Their risk for cancer increases because they spend years with elevated blood levels of both sugar and insulin. While it is impossible to be so precise as to say, 'sugar causes cancer', we can be confident that eating a low-carbohyrate diet reduces the chances of getting cancer and improves the odds of recovery should we develop it.