Avoiding Cooked Meat Carcinogens

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When the muscles of mammals, fish, or birds are cooked at high temperatures carcinogenic chemicals called heterocyclic amines are created that may increase the risk of breast, colon, lung, pancreatic, and prostate cancer (see my last post Estrogens in Cooked Meat). Risky cooking methods don’t just include barbequing, frying, and grilling. Even just baking chicken at around 350o F for 15 minutes leads to significant production of these cancer-causing compounds.

In my video Estrogenic Cooked Meat Carcinogens I showed that these cooked meat carcinogens may stimulate breast cancer cell growth nearly as much as pure estrogen. In PhIP: The Three Strikes Breast Carcinogen I showed that these chemicals may promote breast cancer invasiveness even more than estrogen.

How do you decrease your exposure to these chemicals? As you can see in my 3-min. video Reducing Cancer Risk in Meateaters, fried bacon and fish are the worst, though skinless chicken breast might lead to the greatest exposure given its popularity.  Those eating out may find my video Fast Food Tested for Carcinogens useful, where chicken items from seven restaurant chains were tested to see which was worse—the answer may surprise you. And if there are carcinogens in roasted chicken, what about roasted coffee? See Carcinogens in Roasted Coffee? and Coffee and Cancer.

Women who consume meat very well done, appear to be at nearly 5 times higher risk for breast cancer compared to women who consumed their meats rare or medium done. This, however, raises the so-called “paradox” of preparing meat noted by the Harvard Health Letter. Well-cooked and you risk cancer; undercooked and you risk E. coli food poisoning (a point I also make in Carcinogens in Roasted Chicken?).

Eating boiled meat—not broiled, but boiled in water—is probably the safest. Studies show if you eat meat that never goes above 212 degrees Fahrenheit, both your urine and feces damage DNA significantly less than if you eat meat dry cooked at higher temperatures.  A similar study where they compared the excretion of carcinogens formed in processed meats can be found in Prevention Is Better Than Cured Meat.

PhIP is also found in cigarette smoke, diesel fumes, and incinerator ash, but because the highest levels in food are found in common meats, toxicologists lament “Exposure to PhIP is difficult to avoid because of its presence in many commonly consumed cooked meats, particularly chicken, beef and fish.”  But if you’re able to somehow dodge those meats (and don’t suck on a cigarette, tailpipe, or incinerator smokestack) maybe it’s not so difficult to avoid after all.

The levels of heterocyclic amines flowing through one’s body may drop to zero after refraining from eating meat for just 24 hours. If you practice Meatless Mondays, by Tuesday, morning urine levels of PhIP and MeIQx—one the most potent mutagens ever tested—become undetectable. There are, however, ways even vegetarians may be exposed: cigarette smoke, eggs, cheese, and the popular sports supplement creatine. See my 4-min video Heterocyclic Amines in Eggs, Cheese, and Creatine? for details.

Caution may also be necessary with athletic protein supplementation. See Heavy Metals in Protein Powder Supplements. In general, Some Dietary Supplements May Be More Than a Waste of Money.

Heterocyclic amines are not the only class of meat carcinogens also found in cigarette smoke. See my video When Nitrites Go Bad. While the body can detox itself of both nitrosamines and these cooked meat chemicals within hours or days, some pollutants found in meat can persist in the body. See Industrial Pollutants in VegansFlame Retardant Chemical Contamination, and How Fast Can Children Detoxify from PCBs?

-Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my videos for free by clicking here and watch my full 2012 – 2014 presentations Uprooting the Leading Causes of Death, More than an Apple a Day, and From Table to Able.

Image credit: rhodes/ Flickr

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  • NP

    I use my slow cooker alot…heat is low and cooked slow typically in liquid….any thoughts?

    • Void_Queen

      If you’ve seen his video Uprooting The Leading Causes of Death, you’d know that even if you avoid these carcinogens by slow cooking, you still have a lot of problems to deal with. Animal protein isn’t healthy for your body. It’s responsible for the large spike in the “diseases of affluence” never seen before on such a massive scale until people started consuming animal products. Watch the video I mentioned (that he links in his PS paragraph) and you’ll see that your precautions don’t protect you completely from the health dangers of meat. Veganism is much healthier. Not to mention, if you can survive off a vegan diet and be healthy, why would you want to support needless cruelty to animals?

  • Rheyn

    Do we know whether the same is true of cooking and eating insects?

    • Larry

      THE PERFECT
      DIET

      N.B: FAT IS
      THE MOST IMPORTANT MACRONUTRIENT

      If you are overweight, pre-diabetic or diabetic, or not running on eight
      cylinders, you may be a victim of carbohydrate poisoning! The most killing
      diseases facing us today – including obesity – are a result of the
      overemphasis on carbohydrates. This can be corrected by grading and restricting
      carbohydrates – and emphasizing natural dietary fat and complete animal
      protein.

      Food is our fuel. Much depends on
      what we choose to eat. How long and how well we live depends on how we “fuel”
      our brain, heart, hormones, kidneys, liver, lungs, skin and bones. Human cells,
      tissues, and organs function optimally if they are provided what they need when
      they need it.

      It’s easy to argue that fat is the most important macronutrient. Our 70
      trillion cells are protected by two layers of fat: lipid bilayers. Along
      with protein and water, fat – much of it saturated – is what our bodies are
      made of. Though
      included in our diets, carbohydrates should be chosen carefully and restricted
      in order to keep blood sugar in a narrow healthy range.

      For most people, carbohydrates should be restricted to about 60 grams daily,
      depending on any illness that may be present, or a consideration for a person’s
      environmental conditions. (A lumberjack will eat more than a tailor.) The body
      will more easily maintain itself and regenerate health if carbohydrates do not
      overwhelm hormone systems that keep blood sugar under tight optimum control.

      Carbohydrates
      (carbs) are sugars by another name. Carbohydrates are abundant in fruits,
      vegetables and grains – in boxed cereals – and in all floury or sweet packaged
      products. Remember, in the gut, even healthy-sounding broccoli, cauliflower,
      and zucchini turn into glucose (blood sugar). Our biological requirement for
      carbohydrates is: Zero.

      Some foods are a combination of the three macronutrients. As an example,
      milk contains fat, protein, and carbohydrate. There is protein in many foods
      (beans, corn, grains, mushrooms, peas, seeds and nuts) but only animal foods
      (chicken, cheese, eggs, fish, organ meat, pork, and red meat) provide complete
      high value protein. (Egg white is pure protein.)

      The Perfect Diet emphasizes complete animal protein for the maintenance and
      regeneration of the body and high octane fats to provide energy for – among
      other things – the digestion and assimilation of protein. The Perfect Diet is
      not a high protein diet; it’s a high fat diet that offers strength and energy
      and it’s simple to follow.

      The first
      meal of the day should include fat and protein – about 30 grams of protein
      before noon. Good quality eggs – 7 grams of protein each – provide high value
      protein and many other key nutrients (choline). If you eat a 3 or 4 egg omelet
      before noon, you may not be hungry until dinner. If you eat high value foods,
      you may not need to eat as much.

      As our main
      fuel, we must choose between fats and carbohydrates. Emphasizing two fuels is a
      mistake. Our bodies react adversely to “mixing fuels.” Since fats are energy
      and nutrient dense – and don’t raise blood sugar – they will more fully provide
      satiety and satisfy the energy needs of the body.

      (In the
      Perfect Diet, there is no need for routine snacking or eating more than two
      meals a day. Eating many small meals a day will result in the digestive organs
      getting no rest which can lead to a variety of digestive tract ailments.)

      On the
      Perfect Diet, we will cut carbs – not calories. Depending on your
      circumstances, you can eat up to 3,000 or more calories a day but you will
      still burn fat. You can pretty much live on steak, chicken, and green salads.
      For breakfast you can eat as many eggs as you like – and bacon too. You can put
      full fat dressing on your salads and butter on your steak.

      Our bodies evolved to run optimally on a diet emphasizing protein and
      natural fat, eggs, fish, and meat. We are suffering today because we are eating
      a diet dominated by carbohydrates; and a high percentage have been milled and refined.
      The basis of the Perfect Diet is restricting the macronutrient (carbohydrate) associated
      with a metabolic disturbance that causes weight gain, hunger, diabetes,
      Metabolic Syndrome, and heart disease.

      This diet can work for you. It’s easy to follow and you can eat as much as
      you want; you’ll never go hungry. Dietary abundance goes hand-in-hand with
      feeling on top of the world. If you need to, you’ll lose inches as well as
      pounds. When you burn fat as a fuel you are moving in the direction of health,
      stabilized blood sugar, lower triglycerides, increased HDL, and energy
      throughout the day.

      Here are the
      Paleo Principles:

      1. Eat foods
      that sustained human beings before we wrecked our health by becoming settled,
      citified farmers. Eat meat, fish, eggs,
      avocados, leafy vegetables, preferably fermented (sauerkraut) or steamed and
      berries, nuts, wild seeds.

      2. Eat foods raised in accordance with their own natural
      environment. The animals you eat should
      eat grass if they have four stomachs.
      The birds you eat should eat worms, bugs and weeds. The plants you eat should be grown in soil
      that does not require pesticides and herbicides.

      3. Eat foods
      that are like a stick of nutritional dynamite, instead of like a wimpy little
      firecracker. Everything you eat should
      provide your body with a concentrated source of nutrients for maintaining,
      building, repairing and fueling your body.
      A bowl of rice is a wimpy firecracker. A piece of grass-raised beef is dynamite.

      4. Eat your
      carbohydrate in accordance with your energy expenditure. Carbohydrate only has one function in the
      human body: to provide energy. If you
      are primarily sedentary at work or at your computer, then don’t eat
      carbohydrates. All they do is give you a SUGAR spike.

      5. Prepare your
      foods the way that humans have traditionally prepared foods. Certain foods require specific handling methods
      in order to make their limited nutrients bioavailable to the human body.

      6. Don’t eat
      things that aren’t food. Food should be
      easily identifiable. Soy milk, protein
      bars and sports drinks are a far cry from any food that exists in the natural
      world. Better nutrition through
      chemistry is A BAD IDEA.

      7. Eat a wide range of traditional, life-giving FATS that
      have not been damaged by processing. Your body can use FATS to make nearly all
      that it needs to survive, along with water.

      8. Eat foods
      that are rich in lacto-bacteria to replenish the micro-organisms of our gut.

      9. Eat some of
      your foods raw including animal foods or slightly cooked i.e., liver. Nutrient content and bioavailability of food
      is affected by preservation and cooking method.

      10. Do not partition
      your food wastefully. If you are eating
      an egg, eat the whole egg. If you are
      eating an animal, eat the organs, muscles and bones.

      11. Get to know
      your food supply. Know your hunters,
      your butchers, your gatherers, your storekeepers and your farmers. Know what foods are produced in your own
      geographic environment.

      12. Know
      yourself. How do you feel, perform and
      look? If the way you feel, perform or
      look isn’t top level, change something about the way you eat, move and care for
      yourself!!!

      The Low Down

      The human body
      is a metabolic marvel comprised of dozens of little systems connecting to
      create one complex system. Food is the fuel, the input, for the systems. Our
      metabolic machinery evolved over hundreds of thousands of years to function optimally
      on select fuels. These fuels were the original, Primal foods of the human
      organism. Over these hundreds of thousands of years our Big Game Hunting, small
      prey capturing, scavenging, foraging, gathering, opportunistic ancestors
      accumulated experience and wisdom about nourishing themselves. They learned to
      preserve and predigest foods to maximize the quality of their metabolic fuel.
      Eventually they learned to cook foods without destroying the important
      nourishing properties of the food, and then they learned to heal the human body
      with food.

      Only recently in the human evolutionary experience, have we
      abandoned all these hundreds of thousands of years of accumulated epicurean
      genius.

      Today we fuel our marvelous, complex metabolic machinery with
      crap invented to create profits for agribusiness.

      We have become dumb eaters.

      As we regain
      our eating intelligence it doesn’t make sense to move back to the savannah and
      put out our fires or climb into our cave and pretend there is a glacier next
      door. It makes sense to fuel our bodies with all the primal human foodstuffs,
      prepared and preserved with accumulated ancestral wisdom and served up for the
      undeniable desires of the human taste buds. Primal, paleolithic food choices,
      handled according to ancient food ways resulting in outrageously good food.

      Human
      beings do not have a biological requirement for carbohydrate.

      We can survive just fine
      without carbohydrate. Many people have done it, entire cultures have done
      it, and you could too if you wanted. You probably don’t, so it makes
      sense to learn how to eat carbohydrates in a way that they will help you
      instead of harming you.

      Carbohydrate is a one-trick pony in terms of your metabolic
      requirements. It is solely used to produce energy for you. When you
      eat carbohydrate in excess of what you need for energy production you will
      store it as body fat because there is NOTHING else for your body to do with
      it!! Your body can’t use it to grow your bones or repair your muscles or
      produce hormones. The best thing you can get from your carbohydrates,
      since our modern life really doesn’t require all that much physical energy, are
      their associated micronutrients.

      Give your carbohydrates a long hard look and be ruthless in
      your assessment of what good they do you. Are they packed with
      minerals? Are they loaded with phytonutrients? Are they brimming
      with antioxidants? Are they dripping with water-soluble vitamins?
      Use the carbohydrates in your diet to flood your body with real, whole food
      sources of critical nutrients.

      It is easy to line up your carbohydrates and pick the very
      best ones. If you pour a cup of water onto your carbohydrate will it be
      cleaner? Or will it turn into mush? If you pour water on fruits or
      vegetables they are more ready to eat!!! If you pour water onto flour,
      cereal, crackers, bread, desserts and candy it will be disgusting!

      You can use the color test. Are your carbohydrates
      white, beige, tan, or brown? Then they are lifeless. They have very
      little to offer you.

      Are they all shades of green, orange, red, yellow, blue,
      purple, pink? Then they have abundant nutrients for you.

      You can also use the raw/cooked test. Would you be
      able to eat a handful of your carbohydrate raw? Would you eat a handful
      of raw rice, raw corn or raw black beans? Only if you wanted a few less
      teeth and a vicious stomachache!! You might not enjoy raw vegetables, but
      they are certainly fine (and some are more nutritious) to consume
      uncooked.

      As carbohydrates go, grains and beans possess the fewest
      nutrients and the most energy (calories). You
      need less calories and more nutrition so choose vegetables as your
      carbohydrates. Many people panic at the
      idea of not stuffing themselves each day with bread, crackers, bagels, pasta,
      rice, beans, cereal, and tortillas. “But what will I eat?!?!?!?!” they
      wail. Below is a very long list of excellent carbohydrate choices.

      When choosing fruits and vegetables, choose those grown in
      the most sustainable manner in the healthiest soil. They will have the
      most nutrition. Choose fruits in season, rotating your choices throughout
      the year just as our ancestors did before refrigerated warehouses and cross-global
      food transport. Choose varieties labeled “heirloom” if possible in order
      to ensure a diverse, safe food supply. Often
      older varieties of fruits, especially apples, contain less simple sugars and
      more nutrients

      • Annoyed

        Yes, heck yes! I feel like crap when I have low fat, low protein and high carb. Total crap. My face is puffy and I get terrible acne and pains all over. Reading this article just makes me think I should stop eating altogether and just drink water. Oh, that causes cancer, too! Maybe we should just not eat or drink anything at all. Coconut oil is awesome.

  • JimChmca

    What about roasted veggies when the outer edges get burned? Does the burned part contain cacinogens?

    • Chelsea

      Its the animal protein that leads to carcinogen production, so no.

      • David Mikkelsen

        Yes all burned food meat or veggies contain carcinogens! :) Don’t eat black friend food. It cause higher risk of cancer. I never eat the burned part of food. I always cut it out and throw it. Google it! I’m not lying! ;)

  • Part time meat-lover

    Is microwaving meats any safer than the other methods?

  • Andrew

    I like the smokey flavor from my previous meat-eating days. My spice purveyor makes a very tasty Mesquite Smoke Powder that I like to add to savory dishes. Is there any health information on this kind of thing, or even Liquid Smoke?

    • http://www.DonForresterMD.com/ Don Forrester MD

      Good question. I asked Dr. Greger the same question because my wife and I use a small amount of liquid hickory smoke in a split pea recipe we make regularly. Dr. Greger said that he knew of no studies and since then I haven’t seen any. However, he would guess and I would agree that continuous exposure of cells to it might reveal damage. However occasional use should not be a problem.

  • HW

    I didn’t know which was the best place to ask, so what’s better: a low chicken based diet or a low bovine meat based diet?

    • http://www.DonForresterMD.com/ Don Forrester MD

      Since each approach is not healthy for you it would depend on what you are trying to accomplish. They both have cholesterol, saturated fats, trans-fats, hormones, antibiotics, dioxins, etc. I would say for weight loss I would go with the lean chicken less calorie dense… of course then you have the arsenic to contend with. If you are trying to build muscle strength you can “dope” by eating steaks which have added male hormones. I would review all the video’s and references on this website and choose your path. While you are at it I would also research the value of a low fat whole plant food diet with Vitamin B12 and consider a third option.

      • Lisa

        Isn’t it the incomplete digestion of protein that contributes to disease and cancer, as well, rather than just consuming animal protein? I thought complete sources of protein were essential for growth and survival. Beans are not going to cut it for a growing child or pregnant woman–look at the Brewer Diet and its incredible results in maternal and infant health. There is something missing from all of this information–maybe that it’s bad to eat cooked animal protein and we should eat it raw or very lightly cooked or maybe that our digestion is so poor and lacking enzymes that we cannot properly digest proteins, hence causing cancer. How about raw pastured milk and raw pastured eggs, or raw fish? What kind of studies have been done on these?

        • Toxins

          As I have posted on NF before from Jeff Novick…

          “Plant protein can meet protein requirements when a variety of plant foods is consumed and energy needs are met. Research indicates that an assortment of plant foods eaten over the course of a day can provide all essential amino acids and ensure adequate nitrogen retention and use in healthy adults; thus, complementary proteins do not need to be consumed at the same meal ”

          http://www.vrg.org/nutrition/2009_ADA_position_paper.pdf

          As Jeff Novick puts it..

          Many say that plants foods are incomplete

          If “incomplete” means not containing all the essential amino acids then…. (the incomplete protein theory)

          1) All plant foods are complete as they contain all the essential amino acids.

          2) the only food that is not a complete protein is an animal food, gelatin.

          If “incomplete” means lacking in sufficient quantity of one or more amino acids…(the limiting amino acid theory)

          1) Getting all the amino acids in at once at the same meal, or even in the same day, as some may suggest, is not necessary due to the amino acid pool, which is a circulating level of amino acids in the blood, that the body can draw from if needed. As long as one follows a whole foods plant based diet, the amino acid pool will maintain a sufficient stock of any potentially needed (or limiting) amino acids.

          2) However, as long as one consumes enough calories, eats a variety of food, and limits junk foods and refined foods, and is not an all fruit diet, then they will get in enough protein and enough amino acids in sufficient quantity. There will be no limiting amino acids

          3) there is some evidence that the amino acids that are slightly lower (but adequate) in plant foods, may actually be a benefit to health and longevity and not a concern. This evidence stems from the fact that eating foods that resemble the protein structure of humans causes the liver to release excess amounts of the growth hormone, IGF-1, which accelerates aging and promotes tumor growth.

          Most every major health organization including the NAS, the WHO and the ADA all recognize these statements to be true.

  • http://www.dietfoods7.com/ simo

    Certainly, the products lean, complete or dietetic have a calorie intake lower than the other, but that does not mean that we can eat at will. These products alone cannot provide a full contribution in indispensable nutrients for the body. Check their composition will allow you to compose menus really balanced. So be careful. http://www.dietfoods7.com/