Vitamin C or E pills do not help prevent cancer in men, concludes the same big study that last week found these supplements ineffective for warding off heart disease.

The public has been whipsawed by good and bad news about vitamins, much of it from test-tube or animal studies and hyped manufacturer claims. Even when researchers compare people’s diets and find that a vitamin seems to help, the benefit may not translate when that nutrient is obtained a different way, such as a pill.