How Scary is Acrylamide?

Acrylamide is a crystalline chemical compound used industrially in dye-, plastic- and paper-making processes, as well as in treating drinking water. It's found in small amounts in caulk and food packaging, but its real cause for concern in the last several years stems from the discovery a decade ago of its presence in food. Since then, researchers have been trying to determine just how concerned we should be over acrylamide in our diets. Of course, labeling anything a “chemical” nowadays and then emphasizing its association with industrial processes (often rightly) offends food consumers of every ilk—not only those looking to stay exclusively “natural,” “organic” and “whole” (though these terms can themselves mislead because they frequently lack scientific meaning when used in broad marketing contexts).

Beyond the disconcerting fact of its presence simultaneously in certain foods and in non-food manufacturing applications, there are several reasons that have so far led groups like the American Cancer Society and the National Cancer Institute at the National Institutes of Health to recommend limiting your dietary intake of acrylamide.

The first of these is that acrylamide has been found to increase the risk of several types of cancer when given to lab animals in their drinking water. The doses of acrylamide given in these studies have been as much as 1,000 to 10,000 times higher than the levels people might be exposed to in foods, so a bit like the saccharin-cancer scare of the 1970s, which was later widely debunked, it's hard to know if these results would apply to people as well. However, it's usually wise to minimize human exposure to substances that cause cancer in animals.

Another reason why health experts stop short of ignoring acrylamide in food is that it is found in cigarette smoke. Cigarette smoking has been linked to so many long-term health problems for so long that one modern tendency is to avoid pinpointing one or two specific aspects of it—tar, carbon monoxide intake—as the sole culprits. And for smokers, the major potential source of acrylamide exposure is cigarette smoke.

In a similar way, a third reason scientists are wary of acrylamide—and why an indication to limit it in the diet is easy to make and perhaps only beneficial—is that, with one significant exception, the chemical is found in foods we no longer consider healthy. Foods such as french fries and potato chips seem to have the highest levels of acrylamide; in 2002, researchers in Sweden found the chemical acrylamide in food for the first time by looking at a variety of carbohydrate-rich foods that were fried or baked at high temperatures. Acrylamide forms from sugars and an amino acid that are naturally in food (it does not come from food packaging or the environment). It does not appear to be in raw foods themselves. The unhealthiest cooking method, deep frying, seems to produce the highest amounts.

Still, fried foods are not the only source of acrylamide. It's formed when certain starchy foods are cooked at temperatures above about 250° F, including by baking, roasting, and broiling. Toasting bread can produce it. And longer cooking times can increase the amount of acrylamide in foods further. Despite initial ingredients, cooking methods like boiling, steaming, and microwaving appear less likely to produce acrylamide.

WORST PRACTICES

cigarette smoking

eating burnt toast or popcorn

frying potatoes (or other starchy
vegetables) to a dark crisp

frying potatoes to a light brown color

refrigerating starchy foods before cooking at high temperatures

BETTER PRACTICES

roasting or baking potatoes at medium temperature

BEST PRACTICES

boiling or microwaving starchy foods

soaking foods before high-temperature cooking

NOTES:

coffee beans are already high-temperature roasted—no consumer steps can be taken

natural/organic foods won't help—acrylamide is introduced naturally in the cooking process

In response to concerns about the potential risk, the FDA began to analyze a variety of U.S. food products for acrylamide. In addition to carbohydrate-rich foods, coffee (again, a plant-based food) was found to be a food source of acrylamide. This has to do with the fact that the beans are roasted at very high temperatures prior to grinding and brewing; for this reason there is not yet a good solution to reducing acrylamide exposure from coffee. The health benefits of coffee have been touted in recent years, further delineating the ongoing gray areas of best nutrition practices. Do note also that regardless of cooking methods, acrylamide does not form in significant amounts in dairy, meat, and fish products, some of which have their own potentially negative influence on health.

Perhaps in the bigger picture, acrylamide is but one of many compounds in the diet that shall remain on the radar with an eye toward minimizing, but need not be eliminated at the expense of the health benefits of the healthier foods that deliver it, as part of a balanced meal plan. Dozens of studies have looked at whether people who eat more of these foods might be at higher risk for certain cancers. Most of the studies conducted so far have not found an increased risk of cancer in humans. For some types of cancer—including ovarian, kidney, and endometrial cancers—the results have been mixed, but there are currently no cancer types for which there is clearly an increased risk related to acrylamide intake.

Most of these studies have been limited by certain factors; for example, many of them have relied on food questionnaires filled out only every couple of years. These questionnaires may not have accounted for all dietary sources of acrylamide. In addition, people may not accurately remember what they've eaten when asked in personal interviews or through questionnaires. For now, it's probably a good health practice to limit acrylamide intake, and more research is certainly called for.

As always, the hope is that common sense prevails: For most people, whole grains still have an important role in the diet (gluten-free foods are often notoriously low in fiber). Yet minimizing deep-fried starchy vegetables is certainly a good idea, with an added reason behind it now that acrylamide appears more prevalent in these foods. There are presently about as many good reasons to avoid (caffeinated) coffee as not; if your pick-me-up helps you with portion control and gets you on the treadmill later in the day, keep it, in moderation. And the low-fat, nutrient-rich steamed mashed potato dish you've heard you should banish on the contrary has its occasional place at the balanced table.

And to the marketers pressing us all to primarily focus on terms like “natural” and “organic,” a word of caution: Acrylamide is 100% natural. Since it's formed from only natural chemicals in food during cooking, acrylamide levels in cooked organic foods are similar to levels in cooked non-organic foods. It may be common sense but it bears repeating: Organic or natural isn't always harmless.

American Cancer Society, Oct. 1, 2013, Carcinogens at Home: Acrylamide,
http://www.cancer.org/cancer/cancercauses/othercarcinogens/athome/acrylamide

National Cancer Institute, National Institutes of Health, July 29, 2008, Fact Sheet: Acrylamide in Food and Cancer Risk, http://www.cancer.gov/cancertopics/factsheet/Risk/acrylamide-in-food

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