Organic versus Conventional: Which has More Nutrients?

Organic versus Conventional - Which has More Nutrients?.jpeg

Are organic foods safer and healthier than conventional alternatives? Those are two separate questions. Some consumers are interested in getting more nutrients; others are more concerned about getting fewer pesticides. Let's do nutrition first.

As seen in my video, Are Organic Foods More Nutritious?, hundreds of studies have been reviewed and researchers didn't find significant differences for most of the traditional nutrients like vitamins and minerals. They concluded that despite the widespread perception that organically produced foods are more nutritious, they didn't find robust evidence to support that perception. They did, however, find higher levels of phenolic phytonutrients in organic.

These so-called "secondary metabolites" of plants are thought to be behind many of the benefits ascribed to eating fruits and vegetables. Organic fruits and vegetables had between 19 and 69% more of a variety of these antioxidant compounds. The theory was that these phytonutrients are created by the plant for its own protection. For example, broccoli releases the bitter compounds like sulforaphane when the plant is chewed to ward off those who might eat it. Bugs take one bite and say, "Ew, this tastes like broccoli!" But pesticide-laden plants are bitten less by bugs and so may be churning out fewer of these compounds. Plants raised organically, on the other hand, are in a fight for their lives and may necessarily have to produce more protection. That was the theory anyway, but we don't have good evidence to back it up. The more likely reason has to do with the fertilizer; plants given high dose synthetic nitrogen fertilizers may divert more resources to growth rather than defense.

These antioxidants may protect the plant, but what about us? More antioxidant phytonutrients are found in organic vegetables and so yes, they displayed more antioxidant activity, but also more antimutagenic activity. Researchers exposed bacteria to a variety of mutagenic chemicals like benzopyrene, the polycyclic aromatic hydrocarbon found in barbecued meat, or IQ, the heterocyclic amine found in grilled/broiled/fried meats (as well as cigarette smoke), and there were fewer DNA mutations in the petri dishes where they added organic vegetables compared to the petri dishes where they added conventional vegetables.

Preventing DNA damage in bacteria is one thing, but what about effects on actual human cells? Organic strawberries may taste better, and have higher antioxidant activity and more phenolic phytonutrients, but what happens when you stack them up head-to-head against human cancer cells? Extracts from organically grown strawberries suppressed the growth of colon cancer cells and breast cancer cells significantly better than extracts from conventional strawberries. Now this was dripping strawberries onto cancer cells growing in a petri dish, but as I showed in Strawberries versus Esophageal Cancer, there are real life circumstances in which strawberries come into direct contact with cancerous and precancerous lesions, and so presumably organic strawberries would work even better, but they haven't yet been tested in clinical trials.

Although in vitro studies show higher antioxidant and antimutagenic activity as well as better inhibition of cancer cell proliferation, clinical studies on the impact of eating organic on human disease simply haven't been done. Based on antioxidant phytonutrient levels, organic produce may be considered 20 to 40% healthier, the equivalent of adding one or two serving's worth to a five-a-day regimen. But organic produce may be 40% more expensive, so for the same money you could just buy the extra servings worth of conventional produce. From a purely nutrients-per-dollar standpoint, it's not clear that organic foods are any better. But people often buy organic foods to avoid chemicals, not because they are more nutritious. For more on the best available science comparing the nutritional content, pesticide risk, heavy metal toxicity, and food poisoning risk of organic versus conventionally raised foods )including practical tips for making your own DIY fruit and veggie wash), see:

I imagine that the reaction to this series will be similar to that for the one I did on GMO foods, riling up critics on both sides of the debate:

More on the nutritional implications of stressed-out plants here:

Production method aside, in vitro, Which Fruit Fights Cancer Better?

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Sally Plank / Flickr. This image has been modified.

Original Link

Organic versus Conventional: Which has More Nutrients?

Organic versus Conventional - Which has More Nutrients?.jpeg

Are organic foods safer and healthier than conventional alternatives? Those are two separate questions. Some consumers are interested in getting more nutrients; others are more concerned about getting fewer pesticides. Let's do nutrition first.

As seen in my video, Are Organic Foods More Nutritious?, hundreds of studies have been reviewed and researchers didn't find significant differences for most of the traditional nutrients like vitamins and minerals. They concluded that despite the widespread perception that organically produced foods are more nutritious, they didn't find robust evidence to support that perception. They did, however, find higher levels of phenolic phytonutrients in organic.

These so-called "secondary metabolites" of plants are thought to be behind many of the benefits ascribed to eating fruits and vegetables. Organic fruits and vegetables had between 19 and 69% more of a variety of these antioxidant compounds. The theory was that these phytonutrients are created by the plant for its own protection. For example, broccoli releases the bitter compounds like sulforaphane when the plant is chewed to ward off those who might eat it. Bugs take one bite and say, "Ew, this tastes like broccoli!" But pesticide-laden plants are bitten less by bugs and so may be churning out fewer of these compounds. Plants raised organically, on the other hand, are in a fight for their lives and may necessarily have to produce more protection. That was the theory anyway, but we don't have good evidence to back it up. The more likely reason has to do with the fertilizer; plants given high dose synthetic nitrogen fertilizers may divert more resources to growth rather than defense.

These antioxidants may protect the plant, but what about us? More antioxidant phytonutrients are found in organic vegetables and so yes, they displayed more antioxidant activity, but also more antimutagenic activity. Researchers exposed bacteria to a variety of mutagenic chemicals like benzopyrene, the polycyclic aromatic hydrocarbon found in barbecued meat, or IQ, the heterocyclic amine found in grilled/broiled/fried meats (as well as cigarette smoke), and there were fewer DNA mutations in the petri dishes where they added organic vegetables compared to the petri dishes where they added conventional vegetables.

Preventing DNA damage in bacteria is one thing, but what about effects on actual human cells? Organic strawberries may taste better, and have higher antioxidant activity and more phenolic phytonutrients, but what happens when you stack them up head-to-head against human cancer cells? Extracts from organically grown strawberries suppressed the growth of colon cancer cells and breast cancer cells significantly better than extracts from conventional strawberries. Now this was dripping strawberries onto cancer cells growing in a petri dish, but as I showed in Strawberries versus Esophageal Cancer, there are real life circumstances in which strawberries come into direct contact with cancerous and precancerous lesions, and so presumably organic strawberries would work even better, but they haven't yet been tested in clinical trials.

Although in vitro studies show higher antioxidant and antimutagenic activity as well as better inhibition of cancer cell proliferation, clinical studies on the impact of eating organic on human disease simply haven't been done. Based on antioxidant phytonutrient levels, organic produce may be considered 20 to 40% healthier, the equivalent of adding one or two serving's worth to a five-a-day regimen. But organic produce may be 40% more expensive, so for the same money you could just buy the extra servings worth of conventional produce. From a purely nutrients-per-dollar standpoint, it's not clear that organic foods are any better. But people often buy organic foods to avoid chemicals, not because they are more nutritious. For more on the best available science comparing the nutritional content, pesticide risk, heavy metal toxicity, and food poisoning risk of organic versus conventionally raised foods )including practical tips for making your own DIY fruit and veggie wash), see:

I imagine that the reaction to this series will be similar to that for the one I did on GMO foods, riling up critics on both sides of the debate:

More on the nutritional implications of stressed-out plants here:

Production method aside, in vitro, Which Fruit Fights Cancer Better?

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Sally Plank / Flickr. This image has been modified.

Original Link

Treating Pancreatic Cancer with Turmeric Curcumin

NF-May26 Turmeric Curcumin and Pancreatic Cancer.jpeg

Pancreatic cancer is among the most aggressive forms of human cancer, characterized by a very high mortality rate. It represents the fourth leading cause of cancer death in United States, killing 32,000 people annually. With a five-year survival rate of only three percent and a median survival rate of less than six months, pancreatic cancer carries one of the poorest prognoses. The diagnosis of pancreatic cancer is one of the worst things a doctor ever has to tell a patient. The only FDA-approved therapies for it, Gemcitabine and Erlotinib, produce objective responses in less than ten percent of patients, while causing severe side-effects in the majority. There is a desperate need for new options.

Clinical research to test new treatments is split into phases. Phase I trials are just to make sure the treatment is safe, to see how much you can give before it becomes toxic. Curcumin, the natural yellow pigment in the spice turmeric has passed a number of those. In fact, there was so little toxicity, the dosing appeared limited only by the number of pills patients were willing to swallow.

Phase II trials are conducted to see if the drug actually has an effect. Curcumin did, in 2 of the 21 patients that were evaluated. One patient had a 73 percent tumor reduction, but the effect was short-lived. One lesion remained small, but a curcumin-resistant tumor clone emerged. The other patient, who had a stable disease for over 18 months, showed slow improvement over a year. The only time that patient's cancer markers bumped up was during a brief three-week stint where the curcumin was stopped.

So curcumin does seem to help some patients with pancreatic cancer, and most importantly, there appears to be little downside. No curcumin-related toxic effects were observed in up to doses of eight grams per day. What happens after eight grams? We don't know because no one was willing to take that many pills. The patients were willing to go on one of the nastiest chemotherapy regimens on the planet, but didn't want to be inconvenienced with swallowing a lot of capsules.

The only surefire way to beat pancreatic cancer is to prevent it in the first place. In 2010 I profiled a study conducted by the National Institutes of Health, the largest such study in history, which found that dietary fat of animal origin was associated with increased pancreatic cancer risk.

Which animal fat is the worst? The second largest study (highlighted in my video: Turmeric Curcumin and Pancreatic Cancer) has since chimed in to help answer that question. Researchers found that poultry was the worst, with 72 percent increased risk of pancreatic cancer associated with every 50 grams of daily poultry consumption. Fifty grams is just about a quarter of a chicken breast. The reason white meat came out worse than red may be because of the cooked meat carcinogens in chicken, the heterocyclic amines that build up in grilled and baked chicken. These mutagenic chemicals have been associated with a doubling of pancreatic cancer risk (See Estrogenic Cooked Meat Carcinogens).

Meat has been associated with significantly increased risk, whereas fake meat is associated with significantly less risk. Those who eat plant-based meats like veggie burgers or veggie dogs three or more times a week had less than half the risk of fatal pancreatic cancer. Legumes and dried fruit appear to be similarly protective.

My grandfather died of pancreatic cancer. By the time the first symptom arose, a dull ache in his gut, it was too late. That's why we need to work on preventing it.

I previously touched on pancreatic cancer prevention in Poultry Exposure Tied to Liver and Pancreatic Cancer and attempts at pancreatic cancer treatment in Gerson Therapy for Cancer and Gerson-style Therapy vs. Chemotherapy.

For more on the heterocyclic amine cooked meat carcinogens:

I've done a bunch of videos on turmeric and various cancers:

And more on this amazing spice (and more to come):

In health,
Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live year-in-review presentations Uprooting the Leading Causes of Death, More Than an Apple a Day, From Table to Able, and Food as Medicine.

Image Credit: Sara Marlowe / Flickr

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Do Dietary Toxins Contribute to Hand Tremors?

NF-Nov26 Essential Tremor and Diet.jpg

Essential tremor, affecting 1 in 25 adults over 40 and up to 1 in 5 of those in their 90s, is one of the most common neurological diseases. In addition to the potentially debilitating hand tremor, there can be other neuropsychiatric manifestations, including difficulty walking and various levels of cognitive impairment.

Might beta-carboline neurotoxins play a role in essential tremor? Harmane is one of the most potent of the tremor-producing neurotoxins. Expose people to harmane, and they develop tremors; take it away, and the tremors disappear. What if we're exposed long-term? A recent study at Columbia University, highlighted in my video, Essential Tremor and Diet, found that those with essential tremor have much higher levels of this toxin in their bloodstream compared to those without tremor. Furthermore, the higher the harmane levels, the worse the tremor. The highest levels are found in those who have both essential tremor and cancer, suggesting harmane may be playing a role in both diseases.

How did folks get exposed to these chemicals? Primarily through meat: beef, pork, fish, and especially chicken. So if this potent, tremor-producing neurotoxin is concentrated in cooked muscle foods, is meat consumption associated with a higher risk of essential tremor? Another Columbia University study found that men who ate the most meat had 21 times the odds of essential tremor. To put that in context, if we go back to the original studies on smoking and lung cancer, we see that smoking was only linked to about 14 times the odds, not 21.

Blood levels of this neurotoxin may shoot up within five minutes of eating meat. Five minutes? It's not even digested by then. This rapid uptake is indicative of significant absorption directly through the mouth straight into the bloodstream, bypassing the stomach and, most importantly, bypassing the detoxifying enzymes of the liver. This may lead to higher exposure levels in peripheral organs, like the brain.

Due to its high fat solubility, harmane accumulates in brain tissue, and, using a fancy brain scan called "proton magnetic resonance spectroscopic imaging," higher harmane levels have been linked to greater metabolic dysfunction in the brains of essential tremor sufferers.

Harmane is also found in certain heated plants, like tobacco. A broiled chicken breast has about 13 micrograms of harmane, and cigarettes average about one microgram, so a half pack of cigarettes could expose us to almost as much of this neurotoxin as a serving of chicken. Harman is created when tobacco is burned, and also when coffee beans are roasted. However, coffee intake has not been tied to increased risk (and neither has tobacco for that matter), so it may be something else in meat that's to blame for the 2,000 percent increase in odds for this disabling brain disease.

I also have a few videos about the other major tremor condition, Parkinson's Disease: Preventing Parkinson's Disease with Diet and Treating Parkinson's Disease with Diet

Other compounds created in cooked meats may also have implications for cancer risk:

-Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live year-in-review presentations Uprooting the Leading Causes of Death, More Than an Apple a Day, From Table to Able, and Food as Medicine.

Image Credit: Gennaro D'Orio / Flickr

Original Link

Why Deep Fried Foods May Cause Cancer

NF-Jul21 Cancer Risk from French fries.jpg

In the latest study on dietary patterns and breast cancer risk among women, healthier eating was associated with eliminating three-quarters of the odds of breast cancer, whereas less healthy eating was associated with up to nearly eight times the odds. Included in the unhealthy eating pattern was the consumption of deep-fried foods, which have previously been linked to breast cancer, pancreatic cancer, lung cancer, oral and throat cancers, esophageal cancer, and cancer of the voicebox. No deep fried foods? What's a Southern belle to do? Instead of deep fried foods, how about the traditional Southern diet, characterized by high intakes of cooked greens, beans, legumes, cabbage, sweet potatoes and cornbread, which may reduce the risk of invasive breast cancer significantly.

What about the consumption of deep-fried foods and risk of prostate cancer? Researchers at the Fred Hutchinson Cancer Research Center and the University of Washington found that eating French fries, fried chicken, fried fish, and doughnuts was associated with about a third greater odds of prostate cancer. After stratifying for tumor aggressiveness, they found slightly stronger associations with more aggressive disease, suggesting that regular intake of deep-fried foods may contribute to the progression of prostate cancer as well.

What in deep fried foods is so bad for us? Just heating oil that hot can generate potentially carcinogenic compounds, and then known carcinogens such as heterocyclic amines and polycyclic aromatic hydrocarbons form when the muscles of chickens and fish are cooked at that temperature. Deep-fried plants, on the other hand, can form acrylamide.

I did a video about acrylamide back in 2008, suggesting it's a probable human carcinogen (See Acrylamide in French Fries). Since then, studies have suggested pregnant women may want to cut back on French fries to protect the growth of their baby's body and brain. Based on a study (highlighted in my video, Cancer Risk from French Fries) feeding people a little bag of potato chips every day for a month, it now seems acrylamide may also cause inflammation as well, which could explain its purported role in cancer progression.

Acrylamide intake has been associated with endometrial cancer, ovarian cancer, lung cancer, kidney cancer, and esophageal cancer. How much cancer risk are we talking about? Taiwanese researchers examined lifetime cancer risk and French fry consumption. The researchers picked on French fries because they comprise by far the greatest percentage contribution of acrylamide to the diets of children. They estimated that, at most, one or two boys and girls out of every ten thousand would develop cancer eating French fries that they would otherwise not have developed if they hadn't eaten French fries. So it's not as bad as eating something like fried fish, or fried chicken, but how much is that saying?

The level of cancer risk in both boys and girls associated with French fries depends on how long and hot they're fried. In Europe, the food industry swore that they'd self-regulate and control fry times to decrease acrylamide levels, but we've yet to see any subsequent change in acrylamide levels in French fries.

Researchers continue to urge that the cooking temperature should be as low as possible and the cooking time should be as short as possible, "while still maintaining a tasty quality" of course. We wouldn't want to reduce cancer risk too much--they might not taste as good!

Blanching the potatoes first reduces acrylamide formation, but potato chip companies complain that, not only would it muck with the flavor, but it would reduce the nutritional properties by leaching away some of the vitamin C. But if we're relying on potato chips to get our vitamin C, acrylamide is probably the least of our worries.

More on heterocyclic amines:

There are some things we can do to counteract the effects of these carcinogens, though:

I touch on polycyclic aromatic hydrocarbons in Meat Fumes: Dietary Secondhand Smoke and Is Liquid Smoke Flavoring Carcinogenic?
Certain fats may play a role in breast cancer survival as well: Breast Cancer Survival, Butterfat, and Chicken and Breast Cancer Survival and Trans Fat.

-Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live year-in-review presentations Uprooting the Leading Causes of Death, More Than an Apple a Day, and From Table to Able.

Image Credit: Kim Love / Flickr

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Alkylphenol Endocrine Disruptors and Allergies

NF-Apr23 Alkylphenol Endocrine Disruptors and Allergies.jpg

In my video Preventing Childhood Allergies, I noted a study in Japan that found higher maternal intake of meat during pregnancy was significantly associated with about three times the odds of both suspected and physician-diagnosed eczema. The researchers suggest that certain components of meat may affect the fetal immune system. But what about the moms, themselves? A plant-based diet may also help alleviate allergies in adults. See Say No to Drugs by Saying Yes to More Plants and Preventing Allergies in Adulthood.

Seasonal allergies have exploded in Japan in the past few decades, starting with the first reported case in 1964 and now affecting millions every year. We've seen a rising prevalence of allergic diseases around the industrialized world in past decades, but perhaps nothing quite this dramatic.

Some have suggested that profound changes in the Japanese diet may have played a role. Over the latter half of the century total meat, fish, and milk intake rose hundreds of percent in Japan, so researchers decided to look into dietary meat and fat intake and the prevalence of these seasonal pollen allergies. No association with overall fat, but "higher meat intake was significantly associated with an increased prevalence."

Saturated fat wasn't associated with increased prevalence either, so what other constituents in meat may be to blame? The researchers considered the cooked meat carcinogens, the heterocyclic amines, the polycyclic aromatic hydrocarbons, and the nitrosamines.

A new review, highlighted in my video, Alkylphenol Endocrine Disruptors and Allergies, however, raised an intriguing possibility. There's a class of industrial pollutants called alkylphenols, recognized as common toxic endocrine disrupting chemicals that tend to accumulate in the human body and may be associated with allergic diseases. A variety of studies have shown how they may exacerbate allergen-induced inflammation, "suggesting that alkylphenol exposure may influence the onset, progression, and severity of allergic diseases." These toxic xenoestrogens can be found in human breast milk, in our body fat, in our urine, in our bloodstream, and even in the umbilical cord blood going to our babies. How did it get there? Through contaminated food.

It all goes back to a famous study about the reduction of penis size and testosterone levels in alligators living in a contaminated environment. I don't know what you do for a day job, but these researchers observed that a population of juvenile alligators living on one lake in Florida exhibited a "significantly smaller penis size" and lower blood concentrations of testosterone compared to animals on some different lake. The most important difference between the two lakes was that Lake Stubby was fed by relatively polluted waters. They attributed the "short penis phenomenon" to estrogen-mimicking (xenoestrogenic) environmental metabolites of DDT that still pollute our Earth. This seminal work introduced the concept of endocrine disruptors. Environmental xenoestrogens might result in feminization of exposed male animals. And that's just the shriveled tip of the iceberg.

Since then, endocrine-disrupting chemicals have been implicated in the dramatic rise over the last 50 years of diseases like breast cancer, prostate cancer, testicular cancer, diabetes, obesity, and fertility (such as dropping normal sperm counts), genital birth defects such as penile malformations, preterm birth, neurobehavioral disorders in children linked to thyroid disruption, and earlier breast development in young girls. Because genes do not change fast enough to explain these increases, environmental causes must be involved. Since our greatest exposure to the environment is through our gut, it's no surprise that our greatest exposure to these endocrine-disrupting chemicals is through diet.

To find out which foods may contain these alkylphenol endocrine disruptors, check out my video Dietary Sources of Alkylphenol Endocrine Disruptors.

More on endocrine disruptors in:

A different class of chemicals has been found to be associated with smaller penis size in humans. See Chicken Consumption and the Feminization of Male Genitalia.

-Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videoshere and watch my live year-in-review presentations Uprooting the Leading Causes of Death, More Than an Apple a Day, and From Table to Able.

Image Credit: Mark Freeth / Flickr

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Why the Egg-Cancer Link?

NF-Aug21 Why the Egg Cancer-link?.jpg

Two million men in the U.S. are living with prostate cancer -- but that's better than dying from prostate cancer. Catch it when it's localized and the five-year survival is practically guaranteed, but once it really starts spreading, chances drop to one in three. "Thus, identification of modifiable factors that affect the progression of prostate cancer is something that deserves study," noted Dr. Erin Richard and colleagues at Harvard. So, they took more than a thousand men with early stage prostate cancer and followed them for a couple years to see if there was anything in their diet associated with a resurgence of the cancer, such as spreading to the bone.

Compared to men who hardly ate any eggs, men who ate even less than a single egg a day had a significant 2-fold increased risk of prostate cancer progression. The only thing worse was poultry consumption, with up to four times the risk of progression among high-risk men. They think it might be the cooked meat carcinogens that for some reason build up more in chicken and turkey muscle than in other meats. For more on these so-called heterocyclic amines, see my videos: Heterocyclic Amines in Eggs, Cheese, and Creatine?, Estrogenic Cooked Meat Carcinogens, and PhIP: The Three Strikes Breast Carcinogen.

But what about the eggs? Why would less than once-a-day egg consumption double the risk of cancer progression? "A plausible mechanism that may explain the association between eggs and prostate cancer progression is high dietary choline," the researchers suggested. Egg consumption is a determinant of how much choline you have in your blood, and higher blood choline has been associated with a greater risk of getting prostate cancer in the first place. So the choline in eggs may both increase one's risk of getting it and having it spread.

Studies have associated choline consumption not just with getting cancer and spreading cancer, but also with significantly increased risk of dying from it. Those who ate the most had a 70% increased risk of lethal prostate cancer. Another recent study found that men who consumed two and a half or more eggs per week -- that's just like one egg every three days -- had an 81 percent increased risk of lethal prostate cancer.

Maybe that's why meat, milk, and eggs have all been associated with advanced prostate cancer--because of the choline. Choline is so concentrated in cancer cells that doctors can follow choline uptake to track the spread of cancer throughout the body. But why may dietary choline increase the risk of lethal prostate cancer? Dietary choline is converted in the gut to trimethylamine (see my video Carnitine, Choline, Cancer and Cholesterol: The TMAO Connection), so the Harvard researchers speculated that the TMAO from the high dietary choline intake may increase inflammation, which may promote progression of prostate cancer to a lethal disease.

In one of my videos, Eggs and Choline: Something Fishy, I talked about what trimethylamine might do to one's body odor.

In the New England Journal of Medicine, the same Cleveland Clinic research team that did the famous study on carnitine repeated the study, but instead of feeding people a steak, they fed people some hard-boiled eggs. Just as they suspected, a similar spike in that toxic TMAO. So it's not just red meat. And the link between TMAO levels in the blood and strokes, heart attacks, and death was seen even in low-risk groups like those with low-risk cholesterol levels. Thus, because of the choline, eating eggs may increase our risk regardless of what our cholesterol is.

It's ironic that the choline content of eggs is something the egg industry actually boasts about. And the industry is aware of the cancer data. Through the Freedom of Information Act, I was able to get my hands on an email (which you can view in my video, Eggs, Choline, and Cancer) from the executive director of the industry's Egg Nutrition Center to an American Egg Board executive talking about how choline may be a culprit in promoting cancer progression. "Certainly worth keeping in mind," he said, "as we continue to promote choline as another good reason to consume eggs."

With regard to the prevention of prostate cancer progression, chicken and eggs may be the worst foods to eat, but what might be the best? See my video Prostate Cancer Survival: The A/V Ratio.

To prevent prostate cancer in the first place, see videos such as:

What about reversing cancer progression? See Dr. Ornish's work Cancer Reversal Through Diet?, followed up by the Pritikin Foundation: Ex Vivo Cancer Proliferation Bioassay. Flax may help as well (Flaxseed vs. Prostate Cancer).

-Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live year-in-review presentations Uprooting the Leading Causes of Death, More Than an Apple a Day, and From Table to Able.

Image Credit: Christopher Craig / Flickr

Original Link

Why Do Vegan Women Have Fewer Female Cancers?

 

 

 

 

 

 

 

 

NF-Mar18 Why Might Vegetarians Have Less HPV?.jpg

Cervical cancer is now considered a sexually transmitted disease. It was originally suspected as such, but now we have DNA fingerprinting proof that virtually all cervical cancer is caused by a sexually transmitted virus, human papilloma virus, which also causes cancers of the penis, vagina, vulva and throat. HPV is considered a necessary, but not sufficient cause of cancer.

I profile a study in my four minute video, Why Might Vegetarians Have Less HPV?, that shows that while most young women contract HPV,  most don’t get cervical cancer because their immune systems are able to clear out the virus. Within one year, 70 percent of women clear the infection, and more than 90 percent clear it within two years — before the virus can cause cancer.

Might those with particularly strong immune systems clear the virus even faster? That’s what may be behind a new study that found vegetarian women had significantly lower infection rates with HPV, one of many studies reporting lower risk of HPV infection among those eating plant-based diets.

When researchers took a bunch of women with cancer-causing strains of HPV infecting their cervix and followed them out and retested at three months and nine months while analyzing their diets, what did they find? Higher levels of vegetable consumption appeared to cut their risk of HPV persistence in half, doubling one’s likelihood of clearing this potentially cancer-causing infection. And “higher” levels just meant about two or more servings a day. Antioxidants appear to suppress the activation of critical segments of the virus’ DNA. Maybe that’s why smearing green tea on genital warts—also caused by HPV—has been found so effective in clearing them (See my video, Treating Genital Warts with Green Tea).

In terms of preventing cervical cancer, phytonutrients like lutein (found in dark green leafy vegetables) and lycopene (the red pigment in tomatoes) may decrease viral load, thereby decreasing persistence and progression to disease. Bottom line: higher consumption of vegetables may decrease the risk of HPV persistence, which may help explain why a 2013 study found vegan women have significantly lower rates of all female cancers combined, including cancer of the cervix.

Vegetarians also have lower rates (see Vegetarians Versus Healthy Omnivores), but the Adventist Health Study 2 is the first study of cancer rates among thousands of North American vegans. There are other reasons that help explain these results, from lower levels of the cancer-promoting growth hormone IGF-1 (The Answer to the Pritikin Puzzle), the foreign meat molecule Neu5Gc (How Tumors Use Meat to Grow: Xeno-Autoantibodies), and heterocyclines in cooked meat (Estrogenic Cooked Meat Carcinogens) to more of the good stuff (#1 Anticancer Vegetable and Which Fruit Fights Cancer Better?).

Other viruses may actually be found in the food. See, for example:

More on improving immune function with improved nutrition can be found in Boosting Immunity While Reducing Inflammation and Boosting Immunity Through Diet.

-Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live year-in-review presentations Uprooting the Leading Causes of Death and More Than an Apple a Day.

Image credit: Peter Kemmer / Flickr

Original Link

Why Are Eggs Linked to Cancer Progression?

 

 

 

 

 

 

 

 

Why Are Eggs Linked to Cancer Progression?

About two million men in the U.S. are living with prostate cancer, but that’s better than dying from prostate cancer. Catch it when it’s localized and our 5-year survival is practically guaranteed, but once it really starts spreading our chances drop to 1 in 3. So Harvard researchers took more than a thousand men with early stage prostate cancer and followed them for a couple years to see if there was anything in their diet associated with a resurgence of the cancer, such as spread to the bone.

Compared to men who hardly ate any eggs, men who ate even less than a single egg a day had a significant 2-fold increased risk of prostate cancer progression. The only thing worse was poultry (with skin) consumption, which showed up to 4 times the risk of progression among high-risk men. Researchers believe the higher risk might be caused by the cooked meat carcinogens (heterocyclic amines) that build up more in chicken and turkey muscle than in other meats.

But what about the eggs? Why would less than once a day egg consumption double the risk of cancer progression? The Harvard paper suggests that the choline in eggs may increase inflammation.

As I explained in my video Carnitine, Choline, Cancer and Cholesterol: The TMAO Connection, eggs are the most concentrated common source of choline in the American diet, which may increase the risk of cancer emergence, spread, and lethality. Another Harvard study, entitled Choline Intake and the Risk of Lethal Prostate Cancer, found that those with the highest choline intake had a 70% increased risk of fatal prostate cancer. Another recent study found that men who consumed 2 and a half or more eggs per week—that’s just like one egg every three days—had an 81% increased risk of lethal prostate cancer.

In the New England Journal of Medicine the same Cleveland Clinic research team that performed the famous study on carnitine (see my last post Avoid Carnitine and Lethicin Supplements), tried feeding people hard-boiled eggs instead of steak. As they suspected, the egg-eaters experienced a spike of the same TMAO compound associated with red meat consumption (and strokes, heart attack, and death).

It’s ironic that the choline content of eggs is something the egg industry actually boasts about. And they are aware of the cancer connection. Through the Freedom of Information Act I was able to get my hands on an email (displayed in my 9-min video Carnitine, Choline, Cancer and Cholesterol: The TMAO Connection) from the executive director of the industry’s Egg Nutrition Center to an American Egg Board executive talking about how choline may be a culprit in promoting cancer progression: “Certainly worth keeping in mind as we continue to promote choline as another good reason to consume eggs.”

For another behind-the-curtain peek at the egg industry, see Eggs vs. Cigarettes in Atherosclerosis and Egg Industry Blind Spot.

-Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live year-in-review presentations Uprooting the Leading Causes of Death and More Than an Apple a Day.

Image credit: Christopher Craig / Flickr

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