Does Organic Food Prevent Cancer?

Can giving your kids organic fruits and vegetables lower their cancer risks? A recent, widely reported study from the University of Washington says that parents could lower the level of organophosphate pesticides in their children’s bodies by five-sixths if they fed the kids organic-only fruits and vegetables.

Unfortunately, the report misleads parents. Feeding kids organic produce cannot make any significant difference in their exposure to pesticide dangers. Dr. David Klurfeld, a nutritionist at Wayne State University in Detroit, said, “I’m not saying there is no possible health hazard. But I would not change any of my or my family’s eating habits based on this study.”

In the first place, as U.S. Food and Drug Administration (FDA) policies confirm, “the dose makes the poison.” Even table salt is toxic at high enough doses. The FDA sets the allowed limits for pesticide residues at less than a hundredth of the level that might trigger a physical effect in a laboratory rat, and if there’s any question, a thousandth of that dose.

Moreover, the FDA is convinced that pesticides help make fruits and vegetables more attractive, more widely available, and substantially cheaper. This greatly encourages fruit and vegetable consumption, especially in large families and poor families. That’s vital, because the one-fourth of our population that eats the most produce has half the nonsmoking cancer risk of the one-fourth that eats the least. And that is true regardless of how the produce was grown. Fruit and vegetable consumption also lowers our risks of heart disease and brain dysfunction. For obvious reasons, the FDA thinks that protecting our fruits and vegetables with pesticides is important to the nation’s health.

The second reason for Dr. Klurfeld’s skepticism is that government regulators don’t think organophosphates represent a real danger in our food or water. Malathion is the most heavily encountered organophospate pesticide—and the Environmental Protection Agency (EPA) says that the dietary and drinking-water risks from malathion are “low” and “not of concern.” The EPA worries about worker exposure to concentrated malathion, and toddlers playing on malathion-sprayed lawns, but that is by no means a ringing call for organic-only produce.

It is also important t note that the University of Washington did not test the kids’ urine for any of the organic pesticides, such as broadly-toxic copper compounds, or the “likely human carginogen” pyrethrum.

The biggest reason to discount the University of Washington study, however, comes from Dr. Bruce Ames of the University of California-Berkeley (who was honored with the National Science Medal by President Clinton). Dr. Ames says that we get 100,000 times as much cancer exposure from natural pesticides in our foods as from the residues of synthetic pesticides. Fruits and vegetables are particularly high in natural pesticides, because bugs love to eat them—and the plants can’t run away.

For example: caffeic acid, which causes tumors in rats at high doses, is found naturally in coffee, apples, plums, pears, lettuce, potatoes, and celery. Limonene, found in oranges and mangoes, is also a rodent carcinogen. So is safrole, found in many spices. Mushrooms (even organically grown ones) contain carcinogenic hydrazines.

Caffeic acid is the natural carcinogen we’re exposed to most heavily. On average, we ingest nearly 6 tenths of a percent (0.6 percent) per day of the caffeic acid level that triggers danger for a lab rat. (It comes mostly from vegetables and coffee.) In contrast, we’re exposed to about one millionth of the carcinogenic rat dose for the organochloride pesticide lindane. Dr. Ames’ tests show that an average American’s cancer risk from natural caffeic acid is 600,000 times as great as our risk from lindane—yet there is no evidence of cancer dangers linked to coffee drinking. Meanwhile, eating apples and potatoes full of caffeic acid demonstrably lowers our cancer risks.

No wonder that Cynthia Curl, lead author of the University of Washington study, said, “People want to know: what does this really mean in terms of the safety of my kid? But we don’t know. Nobody does.”

If you still prefer to spend the extra money to buy organic produce, go ahead. Just remember that we’d need to create pasture land for another billion cattle to replace the nitrogen that conventional farmers take from the air and organic farmers get from cow manure. An all-organic America would mean that we would have to clear all of our forests for manure production to sustain our current food supply.

To do that in a delusive effort to reduce cancer risks would be a very bad tradeoff indeed.