VOA慢速英语2017--烤吐司会致癌吗？（在线收听）

From VOA Learning English, this is the Health & Lifestyle report.

Many Americans have toasted bread first thing in the morning. For some, the morning meal also includes hash browned potatoes. Or later in the day, they might enjoy potato chips or crispy French fries.

But if you like any of these foods cooked until they are dark brown in color, you might want to limit how much of them you eat.

That is the finding of a British government agency. The Food Standards Agency (FSA) is urging people to avoid eating burnt or very well toasted bread and deeply browned potatoes.

The danger, the agency says, is when starchy foods are cooked until they are very firm or even burnt.

The concern is a chemical called acrylamide. Acrylamide is produced naturally in food during cooking at high temperatures. It has been identified as a possible cancer-causing substance.

New Scientist magazine reports that high levels of acrylamide are present in starchy foods, like potatoes, when they are cooked at temperatures over 120 degrees Celsius. British researchers note that acrylamide can also be present in breakfast cereals, cookies and coffee.

Steve Wearne is the Director of Policy at the FSA. He says most people do not know that the chemical exists or that it could create a health hazard.

The FSA launched a study to identify acrylamide exposure in the British population. Researchers found that most people are exposed to too much of the chemical. They said this contact could increase their overall risk of getting cancer.

How to avoid the risk

The agency even created an expression to help people remember. The FSA suggests people should "Go for the Gold!" when they prepare starchy foods. Heating bread or potatoes to a golden brown, they claim, is healthier than over-cooking them or burning them.

Wearne says the agency is not saying that people should worry “about the occasional meal that’s a bit overcooked.” He said these suggestions are about controlling risk during one’s lifetime.

The agency is also urging people to eat fewer high-calorie foods like potato chips, French fries and cookies -- all of which have acrylamides.

There are other things you can do to limit your exposure to acrylamides.

Experts at New Scientist suggest that you not keep potatoes in the refrigerator. They explain that “at low temperatures, an enzyme breaks down” the sugars in the potato. These sugars can form acrylamide during cooking. They add that frozen foods don’t have this risk. Sugars, like sucrose, do not break down at low temperatures.

Another cooking tip is you can also blanch potatoes before frying. Blanching is heating food briefly in water. This will remove the potato skin and half the sugar, resulting in lower levels of acrylamide.

Scientists have launched other studies to better understand how acrylamide forms in some overcooked foods and how cooking traditions may affect people.

Words in This Story

crispy – adj. appealingly crunchy

starch – n. a substance that is found in certain foods (such as bread, rice, and potatoes) : starchy – adj. containing, consisting of, or resembling starch

acrylamide – n. an amide C3H5NO that is derived from acrylic acid, that polymerizes readily, and that is used in the manufacture of synthetic textile fibers

exposure – n. the condition of being subject to some effect or influence : expose – v. to cause (someone) to experience something or to be influenced or affected by something

occasional – adj. happening or done sometimes but not often : not happening or done in a regular or frequent way

calorie – n. a unit of heat used to indicate the amount of energy that foods will produce in the human body

hazard – n. a source of danger