Diet Doubts

by Howard Fienberg
October 7, 2002

The Food and Drug Administration (FDA) has launched a massive investigation into a possibly cancerous agent in our food. FDA Deputy Commissioner Lester Crawford announced last week that acrylamide, a chemical recently discovered in certain cooked foods, "is a problem" and that "it doesn't need to be in food." Clark University professor Clark Hattis estimated recently that "acrylamide causes several thousand cancers per year in Americans."


Acrylamide appears to be produced when asparagine, a naturally-occurring amino acid, is heated with certain sugars at high temperatures. Designated a possible carcinogen back in 1994 by the International Agency for Research on Cancer, acrylamide was only discovered in food this year, when Swedish scientists announced its discovery in the spring (their study was finally published August 14 in the Journal of Agricultural and Food Chemistry).


If you did not follow the news closely, you might think that acrylamide is only found in junk foods that have already been declared bad for the diet. Some activist groups seem to reinforce this notion. For instance, when the Center for Science in the Public Interest (CSPI) released its own research finding acrylamide in various foods, president Michael Jacobson declared, "There has long been reason for Americans to eat less greasy French fries and snack chips... Acrylamide is yet another reason to eat less of those foods."


However, the junk foods reviled by dieticians are not the sole problem. Acrylamide is produced in just about any food that is grilled, baked or fried at a high temperature (above 280 degrees F) -- and the longer the cooking time, the more acrylamide is produced. About the only way we can consume our food sans acrylamide is to boil it or eat it raw.


CSPI and the Swedish researchers focused primarily on junk food, but acrylamide has reared its head in much more mundane locations. Vegetables, which are supposed to be good for our diets, turn out to be big offenders. Procter & Gamble has claimed that its testing discovered acrylamide in roasted asparagus and banana chips. Fried spinach and, especially, beetroot have tons of it. If sugar is the key in to the production of acrylamide, that might explain why some of the foods with the highest acrylamide (like beetroot) are among those with the most carbohydrates. In fact, the whole acrylamide controversy may feed back into a broader diet debate (which is worse, carbohydrates or fats?).


Diet debates aside, it is acrylamide's possible carcinogenicity which has made it notorious so quickly. However, we only know it to be possibly cancerous because it appears capable of causing cancer in laboratory rats and fruitflies. Lab animals are usually bred for disposition to cancer, and they are fed so much of a given item that they are almost ready to die from over-eating. Given enough time, such an experiment might conceivably lead to such basic necessities as water being declared a "possible carcinogen." So acrylamide causes cancer at concentrations 1,000 times greater than you would find in most human diets. Direct evidence of a similar impact in humans has yet to be found. Researchers speculate that, beyond the research complications described above, linking the chemical to human cancers may be further beleaguered by our long-term resistance. While rats and fruitflies don't cook their foods, humans have been employing the culinary arts for thousands of year -- and we may have developed a resistance to acrylamide because of it.


Guardian reporter Jenni Russell predicts we will see books within a year along the lines of "the Awfully Boring Acrylamide Cookbook." If such a fad takes off, not only will french fries and potato chips start to disappear from menus, so will baked breads, toast and grilled vegetables. Trying to eliminate our exposure to the risks of acrylamide will leave us more vulnerable to bacterial infections, since we'll be eating more raw food, and our overall diets could suffer, as most people will blanch at eating the most healthy of foods if they can only be boiled.


There is no reason for the public to change their eating habits based on any available acrylamide research. And while FDA Deputy Commissioner Crawford may fell there is no need for acrylamide in food, consumers may disagree. Shockingly enough, the public may still want food that tastes good.


NBC Gets It Right


Amidst all the mis-characterization and mis-reporting, an unlikely agent got the story just right. NBC Nightly News, on September 30, offered a great example of good science reporting:


TOM BROKAW: By now, we've gotten used to all the stories about still another food or substance as a suspected source of cancer, but last spring, the news out of Sweden was especially unsettling: french fries and potato chips. How is it that we're finding out about their dangers now, after all of us have eaten a carload apiece over the course of a lifetime? NBC's chief science correspondent Robert Bazell tonight with an answer.


ROBERT BAZELL reporting: A toxic chemical in french fries and other vegetables? How could it happen? Completely naturally. That's the conclusion out today from several laboratories around the world.


Dr. JOSEPH LEVITT (Food & Drug Administration Center for Food Safety): I think the most important thing for the consumers to understand is that this is something that is a natural by-product of the cooking process.


BAZELL: The worry started last spring when Swedish scientists found that potatoes and other vegetables baked or fried at high temperatures had tiny amounts of a chemical called acrylamide. In laboratory animals, acrylamide--which is used in the plastic industry--can cause cancer. But the latest research shows it comes from natural chemicals in the vegetables. A protein fragment called asparagine and sugars cooked together at 280 degrees or more produce tiny amounts of acrylamide. It is part of the process that brings out the brown color and the flavors of cooked food, and it's probably been going on since cave people started cooking.


Dr. LEVITT: Acrylamide, we now realize, has been in food for a long time, but we didn't know. People had not thought to look for it before.


BAZELL: But now they know it is there, the FDA is studying it. At a public hearing today, releasing first findings of the amounts in different foods. They vary widely, even within one food type. French fries and potato chips tend to have the most, but trace amounts were also found in some kinds of chocolates, cereals, crackers, coffee, even small amounts in some baby food.


Within a few years, the FDA plans to issue guidelines to tell people how to avoid the chemicals. But for now, the evidence suggests there is little cause for concern.

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