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Surprising results (to me at least) from research comparing various diets and incidence of several cancers in 11,082 individuals in the Netherlands over a 20 year period. I expected the daily meat eaters to have higher rates of the 3 cancers studied, but no....

Their main conclusion: vegetarians, pescetarians (no meat, but does eat fish), and low-meat consumers did not have a reduced risk of lung, postmenopausal breast, and overall prostate cancer when compared with individuals consuming meat on a daily basis. This is after taking confounders such as smoking into account (because smokers have higher rates of cancers such as lung cancer). The researchers do point out that some other similar studies had mixed results, but that perhaps those studies did not take confounders (variables that distort the results) such as smoking, physical activity levels, alcohol consumption, etc. into account. From the European Journal of Clinical Nutrition:

Vegetarianism, low meat consumption and the risk of lung, postmenopausal breast and prostate cancer in a population-based cohort study

The few prospective studies that examined lung, female breast and prostate cancer risk in vegetarians have yielded mixed results, whereas none have studied the effects of low meat diets. Moreover, little is known about the explanatory role of (non-) dietary factors associated with these diets.The Netherlands Cohort Study—Meat Investigation Cohort (NLCS-MIC)— is an analytical cohort of 11,082 individuals including 1133 self-reported vegetarians (aged 55–69 years at baseline). At baseline (1986), subjects completed a questionnaire on dietary habits and other risk factors for cancer and were classified into vegetarians (n=691), pescetarians (n=389), 1 day per week (n=1388), 2–5 days per week (n=2965) and 6–7 days per week meat consumers (n=5649).

After 20.3 years of follow-up, 279 lung, 312 postmenopausal breast and 399 prostate cancer cases (including 136 advanced) were available for analyses. After adjustment for confounding variables, we found no statistically significant association between meat consumption groups and the risk of lung cancer. As well, no significant associations were observed for postmenopausal breast and overall prostate cancer. After adjustment for confounders, individuals consuming meat 1 day per week were at a 75% increased risk of advanced prostate cancer compared with 6–7 days per week meat consumers.

Vegetarians, pescetarians and 1 day per week meat consumers did not have a reduced risk of lung, postmenopausal breast and overall prostate cancer compared with individuals consuming meat on a daily basis after taking confounders into account.

Although vegetarian diets are primarily defined by the absence of meat and fish, they are also shown to be associated with high intakes of fruits and vegetables and a favorable distribution of non-dietary factors.1, 2 Consequently, vegetarian diets may reduce the risk of different types of cancers through multiple mechanisms, depending on the etiology and preventability of the tumor.3, 4

We previously reported a nonsignificantly reduced risk of vegetarian and low meat diets on colorectal, and especially rectal, cancer5 and set out to study its effect on three other major cancers. Although meat consumption has been hypothesized to be implicated in the etiology of lung, female breast and prostate cancer, data are not consistent across studies and meat subtypes.6, 7, 8However, on the basis of the existing body of literature, vegetarians may be at a lower risk of developing lung cancer (because of lower smoking rates) and to postmenopausal breast cancer (because of lower alcohol consumption, lower body mass index and higher physical activity levels).

Results from this prospective cohort study showed that, in age- and sex-adjusted models, vegetarians and pescetarians were at a reduced risk of lung cancer compared with individuals consuming meat on a daily basis. This effect disappeared after taking confounders, especially smoking, into account. We did not observe an association between the meat consumption group and the risk of post-menopausal breast and overall prostate cancer.

Our null findings regarding post-menopausal breast cancer risk are in line with other prospective studies comparing vegetarians with non-vegetarians and a pooled analysis of five cohort studies on breast cancer mortality. In contrast, the UK Women’s Cohort Study reported a lower post-menopausal breast cancer risk among non-meat consumers compared with high meat consumers,14 although this was not observed in their dietary pattern analyses.15 Vegetarian diets are rich in fiber and soy. Fiber was associated with a reduced risk of breast cancer in a meta-analysis of prospective studies,19 and soy contains isoflavones, which have previously been associated with a significant reduced risk of postmenopausal breast cancer in Asian populations.20 However, compared with the average soy intake in four Asian countries (ranging from 38 to 134 g/day21), the soy product intake among vegetarians in our population was likely too low to exert an effect (~15g per day).

A big question for many adults is: how can one age well and live to a ripe old age? The author of the book The Blue Zones has dedicated a lot of time to studying communities throughout the world where there are a lot of centanarians and they age well (healthy). What are their secrets to aging well? The answer seems to be: while the diets vary, overall they have a lot of plant based whole foods, they have a lot of physical activity, are committed to their families, take time to de-stress, and they have social networks with healthy behaviors. From NPR:

Eating To Break 100: Longevity Diet Tips From The Blue Zones

Want to live to be 100? It's tempting to think that with enough omega-3s, kale and blueberries, you could eat your way there. But one of the key takeaways from a new book on how to eat and live like "the world's healthiest people" is that longevity is not just about food.

The people who live in the Blue Zones — five regions in Europe, Latin America, Asia and the U.S. researchers have identified as having the highest concentrations of centenarians in the world — move their bodies a lot. They have social circles that reinforce healthy behaviors. They take time to de-stress. They're part of communities, often religious ones. And they're committed to their families.

But what they put in their mouths, how much and when is worth a close look, too. And that's why Dan Buettner, a National Geographic explorer and author who struck out on a quest in 2000 to find the lifestyle secrets to longevity, has written a follow up to his original book on the subject. The new book, called The Blue Zones Solution, is aimed at Americans, and is mostly about eating.

Why should we pay attention to what the people in the relatively isolated Blue Zone communities eat? Because, as Buettner writes, their more traditional diets harken back to an era before we Americans were inundated with greasy fast food and sugar. And to qualify as a Blue Zone, these communities also have to be largely free of afflictions like heart disease, obesity, cancer and diabetes. So clearly they're doing something right.

But in a nutshell, Buettner in 2004 rounded up a bunch of anthropologists, demographers, epidemiologists and other researchers to travel around the world to study communities with surprisingly high percentages of centenarians. He and the scientists interviewed hundreds of people who'd made it to age 100 about how they lived, then did a lot of number crunching to figure out what they had in common.A year after that book was published, the team announced they'd narrowed it down to five places that met all their criteria. They gave them official Blue Zone status: Ikaria, Greece; Okinawa, Japan; Ogliastra Region, Sardinia; Loma Linda, Calif.; and Nicoya Peninsula, Costa Rica

In the new book, which was released April 7, Buettner distills the researchers' findings on what all the Blue Zones share when it comes to their diet. Here's a taste: - Stop eating when your stomach is 80 percent full to avoid weight gain. Eat the smallest meal of the day in the late afternoon or evening. Eat mostly plants, especially beans. And eat meat rarely, in small portions of 3 to 4 ounces. Blue Zoners eat portions this size just five times a month, on average. - Drink alcohol moderately and regularly, i.e. 1-2 glasses a day.

Ikaria, Greece You may remember this Blue Zone from Buettner's wonderful 2012 New York Times Magazine article entitled "The Island Where People Forget To Die." As we've reported, health researchers have long praised the Mediterranean diet for promoting brain and physical health and keeping chronic diseases at bay. 

"Their tradition of preparing the right foods, in the right way, I believe, has a lot to do with the island's longevity," writes Buettner. And "what set it apart from other places in the region was its emphasis on potatoes, goat's milk, honey, legumes (especially garbanzo beans, black-eyed peas, and lentils), wild greens, some fruit and relatively small amounts of fish."Ikaria has a few more "top longevity foods:" feta cheese, lemons and herbs like sage and marjoram that Ikarians use in their daily tea...The Ikarians do eat some goat meat, but not often.

Sardinia, Italy ...Buettner writes that the Sardinians explain their exceptional longevity with their assets such as "clean air," "locally produced wine," or because they "make love every Sunday." But when Buettner brought along a researcher to dig deeper, they found that pastoralism, or shepherding livestock from the mountains to the plains, was most highly correlated with reaching 100.

So what are those ancient Sardinian shepherds eating? You guessed it: goat's milk and sheep's cheese — some 15 pounds of cheese per year, on average. Also, a moderate amount of carbs to go with it, like flat bread, sourdough bread and barley. And to balance those two food groups out, Sardinian centenarians also eat plenty of fennel, fava beans, chickpeas, tomatoes, almonds, milk thistle tea and wine from Grenache grapes.

Loma Linda, CalifThere's a Blue Zone community in the U.S.? We were as shocked to learn this as you may be. Its members are Seventh-day Adventists who shun smoking, drinking and dancing and avoid TV, movies and other media distractions. They also follow a "biblical" diet focused on grains, fruits, nuts and vegetables, and drink only water. ...Another key insight? Pesco-vegetarians in the community, who ate a plant-based diet with up to one serving of fish a day, lived longer than vegan Adventists.Their top foods include avocados, salmon, nuts, beans, oatmeal, whole wheat bread and soy milk.