Newsletter #295
Lee Euler, Editor
I thought I'd let you enjoy your Memorial Day cookout before springing this one on you.
Grilled meat just might increase your cancer risk.
So how great is the risk? Bad enough to compel you to give up this great American tradition? Read on to find out...
Are you serving cancer-causing foods from your grill?
Research shows that cooking certain meats at high temperatures creates new chemicals that don't exist in uncooked meat. Some of them may increase your cancer risk. But take heart, there are ways you can reduce your risk.
Grilling creates two dangerous chemicals
Two chemicals are synthesized when a piece of meat encounters fire: heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs).
HCAs form when muscle meats such as beef, pork, fowl, and fish are cooked at high temperatures. The high cooking temperatures cause amino acids (the building blocks of all protein) to react with creatin (a chemical in the muscle), thereby creating HCAs.
Frying and broiling can also produce HCAs, but the charred edges of barbecued meat produce these chemicals in their purest and potentially most dangerous form.
Researchers have identified 17 different HCAs1 linked to stomach, colon, liver and skin cancer — but only in animal studies.2 Though scientists think HCAs can directly damage your DNA and initiate cancer, they have not yet confirmed that HCAs cause cancer in people.
That hasn't stopped the U.S. Department of Health and Human Services from naming HCAs as a possible carcinogen. The National Cancer Institute (NCI) has also studied HCAs.
An NCI study from its Division of Cancer Epidemiology and Genetics studied 176 people diagnosed with stomach cancer and 503 cancer-free people, assessing their diet and cooking habits.
They found that those who ate medium-well or well-done beef had more than three times the risk of stomach cancer compared to those who ate it rare or medium-rare. In addition, those who ate beef four or more times a week doubled their risk of stomach cancer.
Another study also found that those who eat the most barbecued red meat nearly doubled their risk of colon polyps3, compared with those who don't eat them. And as you probably know, colon polyps can develop into colon cancer.
Other studies link colorectal, pancreatic, and breast cancer to high intake of well-done, fried, or barbequed meats.
Just as an aside, cigarette smoke also contains HCAs.
The second chemical, PAHs, form when meat juices drip onto coals or other hot surfaces and create smoke.4 In this case, it's the smoke that contains the carcinogen, which then settles on the surface of the meat. PAHs have been associated with an increased risk of breast and stomach cancer.
HCAs form when muscle meats such as beef, pork, fowl, and fish are cooked at high temperatures. The high cooking temperatures cause amino acids (the building blocks of all protein) to react with creatin (a chemical in the muscle), thereby creating HCAs.
Frying and broiling can also produce HCAs, but the charred edges of barbecued meat produce these chemicals in their purest and potentially most dangerous form.
Researchers have identified 17 different HCAs1 linked to stomach, colon, liver and skin cancer — but only in animal studies.2 Though scientists think HCAs can directly damage your DNA and initiate cancer, they have not yet confirmed that HCAs cause cancer in people.
That hasn't stopped the U.S. Department of Health and Human Services from naming HCAs as a possible carcinogen. The National Cancer Institute (NCI) has also studied HCAs.
An NCI study from its Division of Cancer Epidemiology and Genetics studied 176 people diagnosed with stomach cancer and 503 cancer-free people, assessing their diet and cooking habits.
They found that those who ate medium-well or well-done beef had more than three times the risk of stomach cancer compared to those who ate it rare or medium-rare. In addition, those who ate beef four or more times a week doubled their risk of stomach cancer.
Another study also found that those who eat the most barbecued red meat nearly doubled their risk of colon polyps3, compared with those who don't eat them. And as you probably know, colon polyps can develop into colon cancer.
Other studies link colorectal, pancreatic, and breast cancer to high intake of well-done, fried, or barbequed meats.
Just as an aside, cigarette smoke also contains HCAs.
The second chemical, PAHs, form when meat juices drip onto coals or other hot surfaces and create smoke.4 In this case, it's the smoke that contains the carcinogen, which then settles on the surface of the meat. PAHs have been associated with an increased risk of breast and stomach cancer.
The 4 factors that influence HCA formation
Four factors determine HCA formation in food, so you can influence the risk, short of totally giving up cooked meat. They are (1) temperature, (2) type of food, (3) cooking method, and (4) time.
Temperature is the most important factor. Frying, broiling, and barbecuing create the most HCAs because the meats are cooked at high temperatures.
Researchers found a stunning 3-fold increase in HCAs when the cooking temperature increased from 392 degrees to 482 degrees Fahrenheit. Oven roasting and baking use lower heat and therefore create lower levels of HCAs. Stewing, boiling, and poaching are done at or below 212 degrees F, and so produce negligible amounts of chemicals.
Well-done (versus medium) meats also produce more HCAs, linked to both longer cooking times and usually higher temperature.
HCAs are only found in muscle meats, whereas other protein sources (milk, eggs, cheese, and organ meats) contain very few HCAs whether uncooked or cooked.
The NIH suggests partially cooking your meat in a microwave and then finishing it off on the grill. While that may reduce HCAs, I'm not sure I can recommend a microwave as a safe cooking method either. See my other suggestions coming up…
Temperature is the most important factor. Frying, broiling, and barbecuing create the most HCAs because the meats are cooked at high temperatures.
Researchers found a stunning 3-fold increase in HCAs when the cooking temperature increased from 392 degrees to 482 degrees Fahrenheit. Oven roasting and baking use lower heat and therefore create lower levels of HCAs. Stewing, boiling, and poaching are done at or below 212 degrees F, and so produce negligible amounts of chemicals.
Well-done (versus medium) meats also produce more HCAs, linked to both longer cooking times and usually higher temperature.
HCAs are only found in muscle meats, whereas other protein sources (milk, eggs, cheese, and organ meats) contain very few HCAs whether uncooked or cooked.
The NIH suggests partially cooking your meat in a microwave and then finishing it off on the grill. While that may reduce HCAs, I'm not sure I can recommend a microwave as a safe cooking method either. See my other suggestions coming up…
Put this into perspective
Currently, no one knows for sure how many HCAs Americans eat, nor has a "safe" level been established. Scientists simply do not know at this time how many HCAs are needed for an increased cancer risk.
But many feel that in the grand scheme of cancer prevention, there are much greater risks than grilling. Says Colleen Doyle, M.S., R.D., and director of Nutrition and Physical Activity for the American Cancer Society, "If you're 30 pounds overweight, that puts you at much greater risk for developing a number of cancers (than does eating grilled meats)."
Incidentally, the other missing piece of information in all these studies is the quality of the meat in the first place.
Nowhere in these studies do they discuss the dangers of conventional meats. For example, dangerous newly emerging antibiotic-resistant killer bacteria, E. coli and salmonella all "force" you to overcook your meat to offer some measure of protection… which isn't necessary with grass fed organic meats.
Plus, grass-fed meat should always be cooked at lower temperatures… or it will become tough.
But many feel that in the grand scheme of cancer prevention, there are much greater risks than grilling. Says Colleen Doyle, M.S., R.D., and director of Nutrition and Physical Activity for the American Cancer Society, "If you're 30 pounds overweight, that puts you at much greater risk for developing a number of cancers (than does eating grilled meats)."
Incidentally, the other missing piece of information in all these studies is the quality of the meat in the first place.
Nowhere in these studies do they discuss the dangers of conventional meats. For example, dangerous newly emerging antibiotic-resistant killer bacteria, E. coli and salmonella all "force" you to overcook your meat to offer some measure of protection… which isn't necessary with grass fed organic meats.
Plus, grass-fed meat should always be cooked at lower temperatures… or it will become tough.
What do cancer experts do?
I'm a realist. Rather than urging people to aim for perfection, I try to get them to change a few bad habits here and there. More than 200 million Americans enjoy outdoor cooking, and the typical household cooks outdoors at least 20 times throughout "the season".
So I try to take into account what's going on in the real world. But in my view, 20 times a summer is too often. This should be a once-in-a-while treat.
I'm not a frequent meat-eater — a couple of times a week at most, red meat once a week or less, grilled meat almost never (mostly when I'm a guest at someone's house). Quite aside from high-temperature cooking, there's other evidence that associates high meat consumption with cancer risk.
Roasting and braising, not frying and grilling, are my favorite ways to cook meat. Once you've had a great braise, I don't know why you'd ever want to eat grilled meat.
For the healthy individual, I think meat is okay as a treat once in a while, provided your other habits are good. Cooked properly, animal protein has enormous health benefits that are very hard to get from a pure vegetarian diet.
If you're a cancer patient, most cancer advocates (the Gerson Institute and Bill Henderson, for example) say you should eat absolutely NO meat. It's not served at most of the alternative cancer clinics we've visited. These places are run by first-rate alternative and integrative doctors. I trust their judgment.
On those rare occasions when you do indulge in grilled meat, take these steps. . .
So I try to take into account what's going on in the real world. But in my view, 20 times a summer is too often. This should be a once-in-a-while treat.
I'm not a frequent meat-eater — a couple of times a week at most, red meat once a week or less, grilled meat almost never (mostly when I'm a guest at someone's house). Quite aside from high-temperature cooking, there's other evidence that associates high meat consumption with cancer risk.
Roasting and braising, not frying and grilling, are my favorite ways to cook meat. Once you've had a great braise, I don't know why you'd ever want to eat grilled meat.
For the healthy individual, I think meat is okay as a treat once in a while, provided your other habits are good. Cooked properly, animal protein has enormous health benefits that are very hard to get from a pure vegetarian diet.
If you're a cancer patient, most cancer advocates (the Gerson Institute and Bill Henderson, for example) say you should eat absolutely NO meat. It's not served at most of the alternative cancer clinics we've visited. These places are run by first-rate alternative and integrative doctors. I trust their judgment.
On those rare occasions when you do indulge in grilled meat, take these steps. . .
13 tips for grilling without serving up cancer
Fortunately there are many ways you can reduce your cancer risk while still enjoying this backyard summer tradition.
- I suggest you always choose organic grass-fed meats for what they do contain, as well as for what they don't. Grass fed animals have much higher levels of omega-3 fatty acids, and a much healthier nutritional profile overall.
Grass fed meat has much lower fat content than conventional meat. So conventional meat is much more likely to drip down and form PAH-laced smoke that settles on your meat. In addition, you may want to avoid it for other reasons — such as second hand consumption of fattening and grains (which are genetically modified, more than likely). - In any case, lower the cooking temperature on your grill. Get used to eating your meat medium-rare instead of well-done.
- Use the leanest cuts you can find. Use thinner cuts, which cook more quickly. Be sure your meat is completely defrosted before cooking, to reduce cooking times.
- Cut meat up into cubes, which cook more quickly. Enjoy them as kabobs.
- Don't cook directly over coals. Use indirect cooking methods.
- Keep the grill rack farther from the fire.
- Flip filets before they become charred. Now recommended: flipping every minute or two, to prevent charring.
- Keep your grill really clean! Scrape off charred residue every time you cook, so you don't transfer carcinogenic chemicals to your food the next time you use it.
- Use marinades. Besides creating superb flavor, some studies show it also reduces carcinogens.
The Journal of Agriculture and Food Chemistry says that marinating red meat for two hours significantly reduced HCAs.5,6,7. Beer, wine, lemon, and vinegar are thought to create an "invisible shield" that protects from the formation of HCAs and PAHs.
A Kansas State University study found that rubbing rosemary onto meats before grilling cut HCA levels by up to 100 percent8 — apparently due to its high antioxidant levels. Do basil, mint, sage and oregano offer similar benefits? I don't know, but it's possible.
However, sugary toppings like barbeque sauce tend to burn very easily and should be avoided.
Important Note: Heat any extra marinade you intend to use as a sauce at least three minutes to kill bacteria it picked up from its contact with uncooked meat, poultry or fish. And always marinate meats in the refrigerator to keep bacterial levels low. You have to bring the sauce to a boil to kill microbes. Otherwise, set aside sauce beforehand and don't reuse the marinade. - The best food for grilling is vegetables and fruits, which do not form HCAs. They also provide you with a host of cancer-fighting nutrients and phytochemicals.
In fact, there's some evidence that these natural phytochemicals may convert HCAs to an inactive, stable form that you can easily eliminate from your body.
Try grilling asparagus, bell peppers, carrots, zucchini, eggplant, onion, portobello mushrooms, and even mangoes brushed with a bit of olive oil.
Cruciferous veggies have especially high potential to negate HCAs. One study of men who ate 2½ cups of Brussels sprouts daily for three weeks reduced their DNA damage significantly. Don't like Brussels sprouts? Try broccoli and cabbage instead. - Avoid charred meat like the plague. Cut off offending spots to protect yourself.
- Grill fish instead of meats. They tend to form fewer HCAs.
- Place juicy foods in a foil packet to reduce dripping.
And before you fire up the grill, go enjoy a 40-minute walk — which will help reduce the greater risk of that "extra 30 pounds".
At least there's one silver lining: You may be better off grilling your own meats in your back yard, versus eating meat in a restaurant. That way you're able to control what you eat including how many additives, antibiotics, and other health saboteurs are in your food.
At least there's one silver lining: You may be better off grilling your own meats in your back yard, versus eating meat in a restaurant. That way you're able to control what you eat including how many additives, antibiotics, and other health saboteurs are in your food.
Footnotes:
1http://www.medicinenet.com/
2http://www.cnn.com/2010/
3http://preventcancer.aicr.
4http://www.cnn.com/2010/
5http://www.ncbi.nlm.nih.gov/
6Olga Viegas, L. Filipe Amaro, Isabel M. P. L. V. O. Ferreira, and Olívia Pinho J. Agric. Food Chem., 2012, 60 (24), pp 6235-6240 Publication Date (Web): May 29, 2012 (Article)DOI: 10.1021/jf302227b
7Armindo Melo, Olga Viegas, Catarina Petisca, Olívia Pinho and Isabel M. P. L. V. O. Ferreira J. Agric. Food Chem., 2008, 56 (22), pp 10625-10632 Publication Date (Web): October 24, 2008 (Article)DOI: 10.1021/jf801837s
8http://krex.k-state.edu/
2http://www.cnn.com/2010/
3http://preventcancer.aicr.
4http://www.cnn.com/2010/
5http://www.ncbi.nlm.nih.gov/
6Olga Viegas, L. Filipe Amaro, Isabel M. P. L. V. O. Ferreira, and Olívia Pinho J. Agric. Food Chem., 2012, 60 (24), pp 6235-6240 Publication Date (Web): May 29, 2012 (Article)DOI: 10.1021/jf302227b
7Armindo Melo, Olga Viegas, Catarina Petisca, Olívia Pinho and Isabel M. P. L. V. O. Ferreira J. Agric. Food Chem., 2008, 56 (22), pp 10625-10632 Publication Date (Web): October 24, 2008 (Article)DOI: 10.1021/jf801837s
8http://krex.k-state.edu/
http://cancerdefeated.com/newsletters/This-cooking-method-increases-cancer-risk.html
