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  • Food as Medicine: Preventing & Treating the Most Dreaded Diseases with Diet

  • Good evening.

  • For those of you unfamiliar with my work, every year I read through every issue of every

  • English-language nutrition journal in the world so you don't have to.

  • [Laughter, applause.]

  • Every year my talks are brand new because every year the science is brand new.

  • I then compile the most interesting, the most groundbreaking,

  • the most practical findings to new videos and articles I upload every day,

  • to my nonprofit site, NutritionFacts.org.

  • [Applause.]

  • Everything on the website is free.

  • There's no ads, no corporate sponsorship.

  • It's strictly noncommercial, not selling anything.

  • I just put it up as a public service, as a labor of love.

  • New videos and articles every day on the latest in evidence-based nutrition.

  • In my 2012 review, I explored the role diet may play

  • in preventing, treating, and reversing our deadliest diseases.

  • In 2013, I covered our most common conditions.

  • And in 2014, I went through our leading causes of disability.

  • This year I'd like to address some of our most dreaded diseases,

  • and cancer tops the list in the latest Gallup poll.

  • The #1 cancer killer in the United States of both men and women is lung cancer.

  • But if you look at the rates of lung cancer

  • around the world, they vary by a factor of ten.

  • If there was nothing we could do to prevent lung cancer,

  • you'd assume the rates would be about the same everywhere,

  • I mean if it just happened kind of randomly.

  • But since there's a huge variation in rates, you assume there's some contributing cause.

  • And indeed we now know that smoking is responsible for 90% of lung cancer cases.

  • So, if you don't want to die of the #1 cancer killer by just not smoking,

  • we can take 90% of your risk and throw it out the window.

  • Colorectal cancer is our second leading cause of cancer death,

  • and for that there's an even bigger spread around the world.

  • So it appears colon cancer doesn't just happen, something makes it happen.

  • Well, if our lungs can get filled with carcinogens from smoke,

  • maybe our colons are getting filled with carcinogens from food.

  • Why do African Americans get more colon cancer than native Africans?

  • Why that population?

  • Because colon cancer is extremely rare in native African populations,

  • like more than 50 times lower rates than Americans, white or black.

  • We used to think it was all the fiber that they were eating,

  • However, the modern African diet is highly processed, low in fiber,

  • yet there's been no dramatic increase in colon cancer rates.

  • And we're not just talking low fiber intake.

  • We're talking United States of America low fiber intake,

  • down around half the recommended daily allowance.

  • Yet colon disease still remains rare in Africa, still 50 times less colon cancer.

  • Maybe it's because they're thinner and exercise more?

  • No, they're not, and no they don't.

  • If anything, their physical activity levels may actually be lower than ours.

  • So if they're sedentary like us, eating mostly refined carbs,

  • few plant foods, little fiberlike us, why do they have 50 times less colon cancer?

  • Well, there is one big difference.

  • The diets of both African Americans and Caucasian Americans is rich in meat,

  • whereas the native Africans' diet is so low in meat and saturated fat

  • they have cholesterol levels averaging 139,

  • compared to over 200 in the US

  • So yes, they don't eat a lot of fiber anymore,

  • but they continue to minimize meat and animal fat intake,

  • supporting evidence that perhaps the most powerful determinants

  • of colon cancer risk are the levels of meat and animal fat intake.

  • So why do Americans get more colon cancer than Africans?

  • Maybe the rarity of colon cancer in Africans is associated

  • with their low animal product consumption.

  • But why?

  • Did you ever see that takeoff of the industry slogan,

  • "Beef: It's What's For Dinner."

  • "Beef: It's What's Rotting in Your Colon."

  • I remember seeing that on a shirt with some friends

  • and I was such the party pooperno pun intended

  • explaining that, no, meat is completely digested in the small intestine,

  • and never makes it down into the colon.

  • No fun hanging out with biology geeks.

  • But it turns out I was wrong!

  • It turns out up to 12 grams a day of protein can escape digestion,

  • and when it does, it reaches the colon,

  • it can be turned into toxic substances like ammonia.

  • This degradation of undigested protein in the colon is called putrefaction,

  • so a little meat can actually end up putrefying in our colon.

  • The problem is some of the by-products

  • of this putrefication process can be toxic.

  • The same thing happens with other animal proteins.

  • If you eat egg whites, for example, some of that can putrefy too.

  • So you say, wait a second. There's protein in plants, too.

  • Ah! The difference is that animal proteins tend to contain more sulfur-containing

  • amino acids like methionine, which is found concentrated

  • in fish and chicken, and then eggs.

  • Less in beef and dairy, but much less in plant foods,

  • which can be turned into hydrogen sulfide in the colon,

  • the rotten egg gas that, beyond it doesn't just smell bad,

  • but it can produce changes in the colon that increase cancer risk.

  • Now there is a divergence of opinion as to whether it's the animal fat,

  • cholesterol, or animal protein that's most responsible for the increased cancer risk,

  • but as all three have been shown to have carcinogenic properties,

  • but, I mean, does it really matter since a diet high in one is high in the others.

  • But the protein does more than just putrefy, though.

  • Animal protein consumption causes an increase in blood levels

  • of a cancer-promoting growth hormone called IGF-1.

  • But remove meat, egg whites, and dairy proteins from our diet,

  • and our bloodstream can suppress cancer cell growth about eight times better.

  • An effect so powerful that Dr. Ornish and colleagues appeared able to reverse

  • the progression of prostate cancer without chemo, without surgery,

  • without radiationjust a plant-based diet and other healthy lifestyle changes.

  • The link between animal protein and IGF-1 may help explain

  • why those eating low carb diets tend to die sooner,

  • but not just any low carb dietsspecifically those based

  • on animal sources, whereas actually vegetable-based low carb diets

  • were associated with a lower risk of death.

  • But meat-based low carb diets are high in animal fat as well.

  • So how do we know it wasn't the saturated fat and cholesterol

  • that was killing people off and had nothing to do with the animal protein?

  • What we would need is a study that, you know, follows a few thousand people

  • and their protein intakes out for 20 years or so and just see what happens:

  • who gets cancer, who doesn't; who lives longer?

  • But there's never been a study like that...

  • ...until now.

  • [Laughter.]

  • 6,000 men and women over age 50, across the US, were followed for 18 years

  • and those under age 65 with high protein intakes had a 75% increase in overall mortality,

  • a 4-fold increase in dying from cancer.

  • But not all proteins. Specifically animal protein.

  • Which makes sense given the higher IGF-1 levels in those eating excess protein.

  • Eating animal protein increases IGF-1 levels, which increases cancer risk.

  • The sponsoring university sent out a press release with a memorable opening line:

  • "That chicken wing you're eating could be as deadly as a cigarette—”

  • [Applause.]

  • explaining that eating a diet rich in animal proteins during middle age

  • makes you four times more likely to die of cancer

  • a mortality risk factor comparable to smoking.

  • Look, almost everyone's going to have a cancer cell or pre-cancerous cell.

  • And at some point the question is: does it progress?

  • And that may depend on what we eat.

  • See, most malignant tumors are covered in IGF-1 receptors,

  • but if we have less IGF-1, the tumor may not progress.

  • And it wasn't just the more deaths from cancer.

  • Middle-aged people who eat lots of proteins from animal sources

  • were found to be more susceptible to early death in general.

  • Crucially, the same did not apply to plant proteins like beans,

  • and it wasn't the fat;

  • it was the animal protein that appeared to be the culprit.

  • So what was the response to this revelation that diets high in meat, eggs and dairy

  • could be as harmful to health as smoking?

  • One nutrition scientist replied that it was wrong and potentially dangerous.

  • Not the discovery animal protein might be killing people,

  • but the way they were telling people about it.

  • It could damage the effectiveness of important public health messages.

  • A smoker might think "why bother quitting smoking

  • if my cheese and ham sandwich is just as bad for me?"

  • [Laughter.]

  • You know, that reminds me of a famous Phillip Morris cigarette ad

  • that tried to downplay the risks by saying "you think second-hand smoke is bad,

  • increasing the risk of lung cancer 19%, drinking one to two glasses of milk

  • every day may be three times as bad— 62% increased lung cancer risk.

  • Or doubling the risk frequently cooking with oil,

  • or tripling your risk of heart disease eating nonvegetarian,

  • or multiplying your risk six-fold eating lots of meat and dairy."

  • So, they conclude, let's keep some perspective.

  • [Laughter.]

  • The risk of lung cancer, the risk of second-hand smoke

  • may be well below the risk reported for other everyday activities.

  • So breathe deep, basically. That's like saying,

  • "Oh, don't worry about getting stabbed because getting shot is much worse."

  • How about neither? Two risks don't make a right.

  • [Applause.]

  • Though you'll note, when Phillip Morris bought Kraft,

  • they stopped throwing dairy under the bus.

  • [Brief laughter.]

  • The heme in the ham may also play a role.

  • Heme iron is the form of iron found in blood and muscle,

  • and may promote cancer by catalyzing the formation of carcinogenic compounds.

  • Cancer has been described as a ferrotoxic disease: a disease, in part, of iron toxicity.

  • Iron is a double-edged sword.

  • Iron deficiency causes anemia, but excessive iron may increase cancer risk,

  • by acting as a pro-oxidant, generating free radicals

  • that may play a role in a number of dreaded diseases like stroke.

  • But look, only the heme iron, the blood and muscle iron,

  • not the nonheme iron that predominates in plants.

  • Same with heart diseaseonly the heme iron.

  • Same with diabetesonly the heme iron.

  • And same with cancer.

  • In fact, you can actually tell how much meat someone is eating by looking at their tumors.

  • To characterize the mechanisms underlying meat-related lung cancer development,

  • they asked lung cancer patients how much meat they were eating,

  • and examined the gene expression patterns in their tumors,

  • and identified a signature pattern of heme-related gene expression.

  • Though they just looked at lung cancer,

  • they expect these meat-related gene expression changes to occur in other cancers as well.

  • The safest form of iron then is non-heme iron, found naturally in abundance in whole grains,

  • beans, split peas, chickpeas, and lentils, dried fruits, nuts, and seeds.

  • How much money can be made on beans, though?

  • So the food industry came up with blood-based crisp bread

  • made out of rye and cattle and pig blood,

  • one of the most concentrated sources of heme iron,

  • about two thirds more than chicken blood.

  • Though if blood-based crackers don't sound appetizing,

  • they do have cow blood cookies or blood filled biscuits.

  • The filling does end up "a dark-colored, chocolate-flavored paste

  • with a very pleasant taste."

  • Dark-colored because spray-dried pigs blood

  • can have a darkening effect on the food product's color.

  • But the worry is not the color or the taste.

  • It's the heme iron, which because of the potential cancer risk

  • is not considered safe to add to foods for the general population.

  • This reminds me of nitrosamines, a class of potent carcinogens found in cigarette smoke.

  • They are considered so toxic that carcinogens of this strength in any other

  • consumer product destined for human consumption would be banned immediately.

  • And if that were the case they would have to ban meat.

  • One hot dog has as many nitrosamines and nitrosamides as five cigarettes.

  • And these carcinogens are also found in fresh, unprocessed meat as well: beef, chicken, pork.

  • But practice Meatless Mondays and you could wake up Tuesday morning

  • with nearly all of these carcinogens washed out of your system.

  • So toxic, nitrosamines should be banned immediately,

  • but are still allowed for sale in cigarettes and meat

  • because the carcinogens are found there naturally.

  • It would be illegal to add them, but hey, if they're found... Right?

  • Just like the heme iron, not safe enough to expose the general population to,

  • but allowed for sale at the deli counter.

  • The irony is that the iron and the protein are what the industry boasts about.

  • Those are supposed to be the redeeming qualities of meat: protein and iron,

  • but sourced from animal foods may do more harm than good.

  • And that's not to mention all the other stuff,

  • like the saturated fat, industrial pollutants, and hormones,

  • that may play a role in our third leading cancer killer, breast cancer.

  • Steroid hormones are unavoidable in food of animal origin,

  • but cow milk may be of particular concern.

  • The hormones naturally found in even organic cow's milk

  • may have played a role in the studies that found that a relationship

  • between milk and dairy products with human illnesses,

  • not just like teenagers' acne;

  • but prostate, breast, ovarian and uterine cancers;

  • many chronic diseases plaguing the Western world;

  • as well as male reproductive disorders.

  • From an increased risk of early puberty all the way to endometrial cancer in older women.

  • But hormonal levels in food could be particularly dangerous

  • in the case of vulnerable populations, such as young children and pregnant women

  • in which even a small hormonal intake could mean a large change in metabolism.

  • Look, dairy milk evolved to put a few hundred pounds onto a calf,

  • but the consequences of a lifetime of human exposure

  • to the growth factors in milk have not been well studied.

  • We know milk consumption increases IGF-1, which is linked to cancer,

  • and we're milking cows while they'