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When was the last time you whatched animals cook on the discovery chanel?
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Okies, well i'm Leia and I've been raw for a few months now, but I'm loving it and I have no intention on ever going back.
I found these articles on the National Cancer Institutes websties, so I thought I would share it with all of you.
Lovies, Leia
Heterocyclic Amines in Cooked Meats
Research has shown that cooking certain meats at high temperatures creates chemicals that are not present in uncooked meats. A few of these chemicals may increase cancer risk. For example, heterocyclic amines (HCAs) are the carcinogenic chemicals formed from the cooking of muscle meats such as beef, pork, fowl, and fish. HCAs form when amino acids (the building blocks of proteins) and creatine (a chemical found in muscles) react at high cooking temperatures. Researchers have identified 17 different HCAs resulting from the cooking of muscle meats that may pose human cancer risk.
Research conducted by the National Cancer Institute (NCI) as well as by Japanese and European scientists indicates that heterocyclic amines are created within muscle meats during most types of high temperature cooking.
Recent studies have further evaluated the relationship associated with methods of cooking meat and the development of specific types of cancer. One study conducted by researchers from NCI's Division of Cancer Epidemiology and Genetics found a link between individuals with stomach cancer and the consumption of cooked meats. The researchers assessed the diets and cooking habits of 176 people diagnosed with stomach cancer and 503 people without cancer. The researchers found that those who ate their beef medium-well or well-done had more than three times the risk of stomach cancer than those who ate their beef rare or medium-rare. They also found that people who ate beef four or more times a week had more than twice the risk of stomach cancer than those consuming beef less frequently. Additional studies have shown that an increased risk of developing colorectal, pancreatic, and breast cancer is associated with high intakes of well-done, fried, or barbequed meats.
Four factors influence HCA formation: type of food, cooking method, temperature, and time. HCAs are found in cooked muscle meats; other sources of protein (milk, eggs, tofu, and organ meats such as liver) have very little or no HCA content naturally or when cooked. Temperature is the most important factor in the formation of HCAs. Frying, broiling, and barbecuing produce the largest amounts of HCAs because the meats are cooked at very high temperatures. One study conducted by researchers showed a threefold increase in the content of HCAs when the cooking temperature was increased from 200° to 250°C (392° to 482°F). Oven roasting and baking are done at lower temperatures, so lower levels of HCAs are likely to form, however, gravy made from meat drippings does contain substantial amounts of HCAs. Stewing, boiling, or poaching are done at or below 100°C (212°F); cooking at this low temperature creates negligible amounts of the chemicals. Foods cooked a long time (“well-done” instead of “medium”) by other methods will also form slightly more of the chemicals.
Meats that are partially cooked in the microwave oven before cooking by other methods also have lower levels of HCAs. Studies have shown that microwaving meat prior to cooking helps to decrease mutagens by removing the precursors. Meats that were microwaved for 2 minutes prior to cooking had a 90-percent decrease in HCA content. In addition, if the liquid that forms during microwaving is poured off before further cooking, the final quantity of HCAs is reduced.
One study has evaluated the content of HCAs in fast food restaurants. After evaluating five kinds of meat products from various fast food restaurant chains, the study concluded that there were low levels of HCAs found in fast food meat products due to factors such as cooking temperature and time. The study suggested that greater exposure to HCAs stems from home cooking and cooking in non-fast-food restaurants where food may be cooked to order and where a larger amount of meat is consumed.
Studies are being conducted to assess the amount of HCAs in the average American diet, but at present the maximum daily intake of HCAs in food has not been established. At the moment, no Federal agency monitors the HCA content of cooked meats (how much a person could be eating), there is no good measure of how much HCAs would have to be eaten to increase cancer risk, and there are no guidelines concerning consumption of foods with HCAs. Further research is needed before such recommendations can be made.
However, concerned individuals can reduce their exposure to HCAs by varying methods of cooking meats; microwaving meats more often, especially before frying, broiling, or barbecuing; and refraining from making gravy from meat drippings.
References
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Adamson RH, Thorgeirsson UP, Snyderwine EG, et al. Carcinogenicity of 2-amino-3-methylimidazo[4,5-f] quinoline in nonhuman primates: Induction of tumors in three macaques. Japanese Journal of Cancer Research 1990; 81(1):10-14.
Bjeldanes LF, Morris MM, Felton JS, et al. Mutagens from the cooking of food. II. Survey by Ames/Salmonella test of mutagen formation in the major protein-rich foods of the American diet. Food and Chemical Toxicology 1982; 20(4):357-363.
Bjeldanes LF, Morris MM, Timourian H, Hatch FT. Effects of meat composition and cooking conditions on mutagen formation in fried ground beef. Journal of Agricultural and Food Chemistry 1983; 31(1):18-21.
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Felton JS, Fultz E, Dolbeare FA, Knize MG. Effect of microwave pretreatment on heterocyclic aromatic amine mutagens/carcinogens in fried beef patties. Food Chemical Toxicology 1994; 32(10):897-903.
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Acrylamide is a chemical used primarily for industrial purposes (see Question 1).
Acrylamide is considered a probable human carcinogen, based on data from laboratory animals (see Question 3). Acrylamide has been found in certain foods, with relatively high levels in potato chips and french fries and lower levels in some breads and cereals (see Question 4).
Food and cigarette smoke cause the greatest exposure to acrylamide, though some exposure may come from other sources (see Question 6). Scientists do not yet know whether acrylamide in food poses a health risk for humans (see Question 8).
1. What is acrylamide?
Acrylamide is a chemical compound that occurs as a solid crystal or in liquid solution. Its primary use is to make polyacrylamide and acrylamide copolymers. Trace amounts of the original (unreacted) acrylamide generally remain in these products. Polyacrylamide and acrylamide copolymers are used in many industrial processes, including production of paper, dyes, and plastics, and the treatment of drinking water, sewage and waste. They are also present in consumer products such as caulking, food packaging and some adhesives.
2. What are the known health effects of acrylamide?
Historically, exposure to high levels of acrylamide in the workplace has been shown to cause neurological damage.
3. Does acrylamide increase the risk of cancer?
Acrylamide has not been shown to cause cancer in humans. However, the relationship between acrylamide and cancer has not been studied extensively in humans. Because it has been shown to cause cancer in laboratory rats when given in the animals' drinking water, both the Environmental Protection Agency (EPA) and the International Agency for Research on Cancer (IARC) in Lyon, France, consider acrylamide to be a probable human carcinogen. The National Toxicology Program's Ninth Report on Carcinogens states that acrylamide can be "reasonably anticipated to be a human carcinogen."
4. Is there acrylamide in food?
Recent studies by research groups in Sweden, Switzerland, Norway, Britain and the United States have found acrylamide in certain foods. It has been determined that heating some foods to a temperature of 120 C (248 F) can produce acrylamide. Potato chips and french fries have been found to contain relatively high levels of acrylamide compared to other foods, with lower levels also present in bread and cereals. A joint World Health Organization and Food and Agriculture Organization (WHO/FAO) consultation in June 2002 concluded that the levels of acrylamide in foods pose a major concern and called for more research to determine what the risk is and what should be done.
5. How does cooking produce acrylamide?
In September 2002, researchers discovered that the amino acid asparagine, which is present in many vegetables, with higher amounts in some varieties of potatoes, can form acrylamide when heated to high temperatures in the presence of certain sugars. High-heat cooking methods, such as frying, baking or broiling, are most likely to result in acrylamide formation. Boiling and microwaving appear less likely to form acrylamide. Longer cooking times increase the amount of acrylamide produced when the temperature is high enough.
6. Are there other ways humans are exposed to acrylamide?
There are other ways humans are exposed to acrylamide, but exposure through food is one of the largest sources. Cigarette smoke may be a major source for some people. Exposure to acrylamide from other sources is likely to be significantly less than that from food or smoking, although scientists do not yet have a complete understanding of all the sources. There are some industrial and agricultural uses of acrylamide and polyacrylamide. However, regulations are in place to limit exposure in those settings.
7. Are acrylamide levels regulated?
The EPA regulates acrylamide and has established acceptable levels for air and drinking water, at which exposure is considered to have no effect. These levels are set low enough to counteract any uncertainty arising from the lack of human data on the relationship between acrylamide and cancer. FDA regulates the amount of residual acrylamide in a variety of materials that come in contact with food. There are currently no guidelines governing the presence of acrylamide in food itself.
8. How do the levels of acrylamide in food compare to allowable levels set for drinking water?
In setting its level for acrylamide in drinking water, EPA assumes people drink two liters, approximately four and a half pounds, of water a day. Since people do not eat four and a half pounds a day of foods like french fries or potato chips, a direct comparison of drinking water to these products without considering absolute food intake is inappropriate Scientists also do not know whether the absorption in the gut of acrylamide from food is similar to that from water. The simplest way to think about this is that the levels in food are, as the World Health Organization put it, a major concern. However, scientists still do not know whether the acrylamide that has been in food for thousands of years has any effect on health.
9. Should I change my diet?
The best advice at this early stage in our understanding of this complex issue is to follow established dietary guidelines and eat a healthy, balanced diet that is low in fat and rich in high-fiber grains, fruits, and vegetables.
10. What research is needed?
The WHO/FAO consultation concluded that further research is necessary to determine how acrylamide is formed during the cooking process and whether acrylamide is present in foods other than those already tested. They also recommended population-based studies of those cancers that could potentially develop due to exposure to acrylamide.
For the World Health Organization's press release on acrylamide in food, go to http://www.who.int/foodsafety/chem/chemicals/acrylamide/en/.
For information on acrylamide from the National Toxicology Program's Tenth Report on Carcinogens, go to http://ehp.niehs.nih.gov/roc/toc10.html.
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