Does cooking food release toxins and carcinogens?

The short answer is "yes," based on numerous government studies around the world (including the U.S. CDC, NIH, EPA, etc.), but only if you cook at higher-than-steaming/boiling temperatures. Studies indicate probable links between cancer rates and food fried/grilled at high temperatures (see below).

Thus if you're serious about maintaining good health, you may want to reduce high-temperature cooked foods in your diet. It doesn't mean you have to avoid such foods entirely, because your body can detoxify itself to some extent, via organs like the liver. But the less you abuse your body, the greater your chance of having a healthy life and old age.

There are four common ways to get carcinogens in your diet:

1. Heterocyclic amines (HCAs). High-temperature cooking of meat (beef, pork, chicken, fish, etc.) creates compounds known to cause cancer in laboratory animal tests. The higher the temperature, the worse the problem, especially above 300 degrees Fahrenheit (149C).

2. Polycyclic aromatic hydrocarbons (PAHs). Grilling on an open flame or smoking meat creates known carcinogens.

3. Acrylamide is the vegetarian counterpart to HCAs. High-temperature cooking of potatoes, grains (e.g., toast, cereal), and coffee are known to produce this cancer-causing substance.

4. Exceeding the smoke point of a cooking oil means the oil breaks down and starts to release carcinogens.

You can avoid these carcinogens by:

Cooking more slowly, at a lower temperature (e.g., boiling, steaming, braising, and low-temperature frying). Avoid roasting, baking, grilling, high-temperature frying, or other high-temperature cooking methods. This doesn't mean you can't splurge once in a while.

Using natural gas or propane instead of charcoal for grilling; gas/propane are cleaner-burning

Cleaning your grill of charred bits first.

Microwaving hunks of meat for a minute in the microwave before putting them on the grill, to reduce the time of exposure to high heat.

Avoiding obviously charred pieces of meat. Cut them off.

Avoiding overcooking food (the browner/more charred your toast/fries/meat, the more acrylamide or HCAs).

Eating more vegetables and fruits and less meat, grains, or tubers.

Keeping temperatures below the smoke point of your cooking oil.

Using cookware that spreads heat evenly, so that you don't have a hotspot overheating the center of the pan just because you needed to crank up the burner to increase the temperature at the edge of the pan.

Avoiding coffee, since roasting coffee beans creates acrylamide.

The long answer:

We'll go in order, from HCAs and PAHs to acrylamide and overheating cooking oil:

1. HCAs.

According to the National Cancer Institute (part of the U.S. National Institutes of Health), Heterocyclic amines (HCAs) are chemicals formed when muscle meat (beef, pork, chicken, fish, etc.) is cooked at high temperatures.

How this happens:

Proteins are made out of amino acids. Creatine is also made out of amino acids and is found in muscle tissue. At high temperatures, amino acids, creatine, and sugars react to form HCAs.

Laboratory rodents exposed to very high levels of HCAs (equivalent to thousands of times an adult human's normal dietary exposure to HCAs) develop tumors in the breast, colon, liver, skin, lung, prostate, and other organs, in addition to full-blown cancers. Although adult humans may consume a lot less in HCAs per meal, the concern is that if a lot of HCA exposure over a short period of time causes cancer, then a little HCA exposure over a long period of time may also cause cancer.

Furthermore, Scientists have linked diets high in well-done, fried, or barbecued meat with colorectal, pancreatic, and prostate cancer. These links weren't strong enough for the government to issue guidelines limiting consumption of red meat and smoked foods, and I'm sure that the meat and seafood lobbyists have done their part to ensure that things stay that way.

2. PAHs.

The incomplete combustion of organic matter creates polycyclic aromatic hydrocarbons (PAHs). PAHs have effects such as gastrointestinal, lung, skin, and bladder cancers; accordingly, various U.S. federal agencies such as the Department of Health and Human Services and EPA classify