Does Nature Know Best?: Natural Carcinogens and Anticarcinogens in America s Food

A large number of substances that occur naturally in foods are carcinogenic (cancer-causing) when evaluated by the criteria scientists customarily use to assess the cancer-causing potential of synthetic substances. Other carcinogens are produced by cooking and by the actions of microorganisms. These natural carcinogens are more numerous, more widespread and in some cases more potent than synthetic carcinogens in food.

It is not necessary or practical for consumers to stop eating foods that contain natural carcinogens indeed, nearly every food type contains them, and it is impossible to completely avoid them.

The occurrence of natural carcinogens in foods, particularly plant foods, does not justify changes in Americans' eating habits. Many cancer researchers and nutritionists now recommend that Americans not only increase their intake of fruits and vegetables but also reduce their intake of red meat, alcoholic beverages and fatty foods and reduce their overall caloric intake.

Eating a wide variety of foods is desirable for nutritional reasons, and increasing fruits and vegetables in the diet has always been recognized as good nutritional advice. Fruits and vegetables are beneficial in that they are now known to contain many protective "anticarcinogens" compounds that have been shown to counteract the cancer process initiated by carcinogens.

The common assumption that "natural" is safe and "synthetic" is toxic is contrary to current scientific knowledge. Synthetic chemicals are present in foods at much lower levels than are many naturally occurring carcinogens and toxins. Also, in many cases the synthetic chemicals are less potent carcinogens than the ones that are a natural part of our food. The dose makes the poison.

There is a need for a new perspective on carcinogens one that emphasizes both a substance's carcinogenic potency and the level of human exposure to it rather than whether it is natural or synthetic.

There is a need to distinguish between real and hypothetical hazards and between functional and unnecessary substances when setting regulatory priorities.

More research is needed on natural food components. We need to strike a more even balance between our evaluations of natural substances and synthetic substances in the food supply.

Does Nature Know Best?: Natural Carcinogens and Anticarcinogens in America s Food