The facts: All cells in the body use sugars as fuel. So do cancer cells. While cancer cells in the test-tube have been shown to grow well on glucose, this doesn't mean eating sugar will make cancer cells grow faster or even cause cancer. Even if it were possible to avoid all sugar and somehow stop sugars reaching any cancer cells from other foods like protein and fats, you would be starving your body's healthy cells along with any cancer cells. A healthy diet is the best way to give your body the fuel it needs and avoid weight gain, which does raise cancer risk.