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Category: nutrition

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The following is a list of nutrients that some researchers (from the Institute of Food Technology) think of as especially beneficial to the brain. Other researchers may (or probably will) focus on other nutrients. I am posting it even though I generally dislike articles that talk about "superfoods" or an itemized list of foods that one should eat to the exclusion of others. Because, of course, focusing on some nutrients may leave out many just as important nutrients.

Also, medical thinking changes over time and what was once considered "unhealthy" may later be considered a wonderful food (remember when eggs, nuts, and coconuts were almost considered evil?). And vice versa (remember when margarine with partially hydrogeneated oils and trans-fats was considered healthier than butter?) And study after study says it is better to eat the foods, rather than take supplements. So keep in mind that the following nutrients are found in whole foods and in a varied diet. And when they mention a specific food such as blueberries, remember that ALL berries have benefits (though they vary), so eat a variety of berries. Same with nuts - eat a variety and not just walnuts. From Science Daily:

Eight nutrients to protect the aging brain

Brain health is the second most important component in maintaining a healthy lifestyle according to a 2014 AARP study. As people age they can experience a range of cognitive issues from decreased critical thinking to dementia and Alzheimer's disease. In the March issue of Food Technology published by the Institute of Food Technologists (IFT), contributing editor Linda Milo Ohr writes about eight nutrients that may help keep your brain in good shape.

1. Cocoa Flavanols: Cocoa flavanols have been linked to improved circulation and heart health, and preliminary research shows a possible connection to memory improvement as well. A study showed cocoa flavanols may improve the function of a specific part of the brain called the dentate gyrus, which is associated with age-related memory (Brickman, 2014). {NOTE: good sources are cocoa and dark chocolate}

2. Omega-3 Fatty Acids: Omega-3 fatty acids have long been shown to contribute to good heart health are now playing a role in cognitive health as well....Foods rich in omega-3s include salmon, flaxseed oil, and chia seeds.

3. Phosphatidylserine and Phosphatidic Acid: Two pilot studies showed that a combination of phosphatidylserine and phosphatidic acid can help benefit memory, mood, and cognitive function in the elderly (Lonza, 2014). {NOTE: good sources are fish and meat}

4. Walnuts: A diet supplemented with walnuts may have a beneficial effect in reducing the risk, delaying the onset, or slowing the progression of Alzheimer's disease in mice (Muthaiyah, 2014).

5. Citicoline: Citicoline is a natural substance found in the body's cells and helps in the development of brain tissue, which helps regulate memory and cognitive function, enhances communication between neurons, and protects neural structures from free radical damage.... {NOTE: Citocoline is synthesized in the body from choline, so see foods high in choline}

6. Choline: Choline, which is associated with liver health and women's health, also helps with the communication systems for cells within the brain and the rest of the body. Choline may also support the brain during aging and help prevent changes in brain chemistry that result in cognitive decline and failure. A major source of choline in the diet are eggs. { NOTE: Good sources of choline are eggs, meat, fish, beans, and cruciferous vegetables.}

7. Magnesium: Magnesium supplements are often recommended for those who experienced serious concussions. Magnesium-rich foods include avocado, soy beans, bananas and dark chocolate.

8. Blueberries: Blueberries are known to have antioxidant and anti-inflammatory activity because they boast a high concentration of anthocyanins, a flavonoid that enhances the health-promoting quality of foods. Moderate blueberry consumption could offer neurocognitive benefits such as increased neural signaling in the brain centers.

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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, Calif. There'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.

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There have been a number of studies over the years finding environmental links to testicular cancer (such as some pesticides, smoking, and endocrine disruptors). Now another one - muscle-building supplements with creatine and androstenedione . From Science Daily:

Testicular cancer link found for muscle-building supplements

Men who reported taking muscle-building supplements, such as pills and powders with creatine or androstenedione, reported a significantly higher likelihood of having developed testicular cancer than men who did not use such supplements, according to a new study in theBritish Journal of Cancer. Moreover, said study senior author Tongzhang Zheng, the associated testicular germ cell cancer risk was especially high among men who started using supplements before age 25, those who used multiple supplements and those who used them for years.

"The observed relationship was strong," said Zheng, who led the study at Yale University before joining the Brown University School of Public Health as a professor of epidemiology. "If you used at earlier age, you had a higher risk. If you used them longer, you had a higher risk. If you used multiple types, you had a higher risk." Testicular cancer incidence rose to 5.9 cases per 100,000 men in 2011, from 3.7 cases in 100,000 in 1975, Zheng said. Researchers aren't sure why. The work was inspired by mounting evidence that that at least some supplement ingredients may damage the testes.

To conduct the study, Zheng's research team conducted detailed interviews of nearly 900 men from Massachusetts and Connecticut -- 356 of whom had been diagnosed with testicular germ cell cancer, and 513 who had not. In the interviews, researchers asked the men not only about their supplement use but also about a wide variety of other possible factors such as smoking, drinking, exercise habits, family history of testicular cancer, and prior injury to their testes or groin....The researchers defined "use" as consuming one or more supplements at least once a week for four consecutive weeks or more.

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Macular degeneration is a feared condition, so this study finding a link with calcium supplements and age-related macular degeneration in those 68 and older is a bit alarming. However, it shows association, not causation, because it looked at people only one time. But once again supplements are looking suspect.

Another reason to stick with whole foods, especially leafy greens and fish, and don't smoke. From Medscape:

Calcium Supplementation Associated With Macular Degeneration

Individuals who take more than 800 mg of calcium daily are almost twice as likely to be diagnosed with age-related macular degeneration (AMD) as those who did not, according to the results of a new study published online April 9 in JAMA Ophthalmology.

Caitlin L. M. Kakigi, BA, from the Department of Ophthalmology, University of California, San Francisco, and colleagues evaluated 3191 participants in the 2007 to 2008 National Health and Nutrition Examination Survey (NHANES) aged 40 years and older, including 248 patients with AMD diagnosed by fundus photography. Each participant was surveyed about consumption of dietary supplements and antacids during the 30-day period preceding trial enrollment.

The researchers found the odds of an AMD diagnosis were elevated among participants who reported taking 800 mg of calcium or more daily....The association was strongest in older people,  for those aged 68 years and older. In fact, there was no association between AMD diagnosis and calcium intake in participants younger than 68 years. The average age of participants with AMD in this study was 67.2 years compared with 55.8 years for those without an AMD diagnosis.

Rahul Khurana, MD, a clinical spokesperson for the American Academy of Ophthalmology and a partner at Northern California Retina Vitreous Associates in Mountain View, who was not involved in the study, cautioned that it is an exploratory analysis."It shows association but not causation."

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Note that both eggs and high-fat dairy products were basically considered evil by the medical establishment for many years. Remember egg white omelettes?And now both are thought to have health benefits, especially reducing the risk of diabetes. From Science Daily:

Eating eggs reduces risk of type 2 diabetes, study indicates

Egg consumption may reduce the risk of type 2 diabetes, according to new research...Research has shown that lifestyle habits, such as exercise and nutrition, play a crucial role in the development of the disease. A new study has found that egg consumption was associated with a lower risk of type 2 diabetes as well as with lower blood glucose levels. Men who ate approximately four eggs per week had a 37 per cent lower risk of type 2 diabetes than men who only ate approximately one egg per week. This association persisted even after possible confounding factors such as physical activity, body mass index, smoking and consumption of fruits and vegetables were taken into consideration. The consumption of more than four eggs did not bring any significant additional benefits.

The dietary habits of 2,332 men aged between 42 and 60 years were assessed at the baseline of the Kuopio Ischaemic Heart Disease Risk Factor Study, KIHD, at the University of Eastern Finland in 1984-1989. During a follow-up of 19.3 years, 432 men were diagnosed with type 2 diabetes.

Also note that high meat consumption is linked to higher risk of diabetes. From Science Daily:

High-fat dairy products linked to reduced type 2 diabetes risk

Consumption of high-fat yoghurt and cheese are linked to a reduction in the risk of type 2 diabetes by as much as a fifth, according to new research. High meat consumption, on the other hand, is linked to a higher risk.

However, the new study indicates that it is high-fat dairy products specifically that are associated with reduced risk."Those who ate the most high-fat dairy products had a 23 per cent lower risk of developing type 2 diabetes than those who ate the least. High meat consumption was linked to an increased risk of type 2 diabetes regardless of the fat content of the meat," said Ulrika Ericson, who conducted the study.

The researchers studied the eating habits of 27,000 individuals aged 45 to 74. The participants took part in the Malmö Diet and Cancer study in the early 1990s, in which they provided details of their eating habits. Twenty years on, over ten per cent -- 2 860 people -- had developed type 2 diabetes.

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After reading this article, I looked over my last year's posts and realized that the recent studies posted all found that eating fish showed health benefits (and they did not look at supplements). Once again, a food shows benefits while the supplement is debatable. Current advice: try to eat fish at least twice a week. From the NY Times:

Fish Oil Claims Not Supported by Research

Fish oil is now the third most widely used dietary supplement in the United States, after vitamins and minerals, according to a recent report from the National Institutes of Health. At least 10 percent of Americans take fish oil regularly, most believing that the omega-3 fatty acids in the supplements will protect their cardiovascular health. But there is one big problem: The vast majority of clinical trials involving fish oil have found no evidence that it lowers the risk of heart attack and stroke.

From 2005 to 2012, at least two dozen rigorous studies of fish oil were published in leading medical journals, most of which looked at whether fish oil could prevent cardiovascular events in high-risk populations. These were people who had a history of heart disease or strong risk factors for it, like high cholesterol, hypertension or Type 2 diabetes. All but two of these studies found that compared with a placebo, fish oil showed no benefit.

In theory at least, there are good reasons that fish oil should improve cardiovascular health. Most fish oil supplements are rich in two omega-3 fatty acids — eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) — that can have a blood-thinning effect, much like aspirin, that may reduce the likelihood of clots. Omega-3s can also reduce inflammation, which plays a role in atherosclerosis. And the Food and Drug Administration has approved at least three prescription types of fish oil — Vascepa, Lovaza and a generic form — for the treatment of very high triglycerides, a risk factor for heart disease. But these properties of omega-3 fatty acids have not translated into notable benefits in most large clinical trials.

Like many cardiologists, Dr. Stein encourages his patients to avoid fish oil supplements and focus instead on eating fatty fish at least twice a week, in line with federal guidelines on safe fish intake, because fish contains a variety of healthful nutrients other than just EPA and DHA. “We don’t recommend fish oil unless someone gets absolutely no fish in their diets,” Dr. Stein said.

But some experts say the case for fish oil remains open. Dr. JoAnn Manson, the chief of preventive medicine at Brigham and Women’s Hospital in Boston, said the large clinical trials of fish oil focused only on people who already had heart disease or were at very high risk. Fish oil has also been promoted for the prevention of a variety of other conditions, including cancer, Alzheimer’s and depression. Dr. Manson is leading a five-year clinical trial, called the Vital study, of 26,000 people who are more representative of the general population. Set to be completed next year, it will determine whether fish oil and vitamin D, separately or combined, have any effect on the long-term prevention of heart disease, Type 2 diabetes, and other diseases in people who do not have many strong risk factors.

Dr. Manson says that although she recommends eating fatty fish first, she usually does not stop people from taking fish oil, in part because it does not seem to have major side effects in generally healthy people. “But I do think people should realize that the jury is still out,” she said, “and that they may be spending a lot of money on these supplements without getting any benefit.”

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The research finding that eating fruits and vegetables with high pesticide residues has a negative effect on sperm is disturbing. It wasn't the amount of fruits and vegetables eaten, it was eating fruits and vegetables with high levels of pesticide residues. Yes, the study does have some limitations (for example, a one time analysis, looked at men at a fertility clinic and not the general population), but...even with these limitations, the results are disturbing.

Earlier studies of children showed that switching to an organic diet has almost immediate results of reducing pesticide residues in the body (OP Pesticides in Children’s Bodies: The Effects of a Conventional versus Organic Diet). So the advice here is try to increase the amounts of organic fruits and vegetables in the diet, especially those with high pesticide residue levels.

Fruit or vegetables that were low in pesticide residues included peas, beans, grapefruit and onions. Those that had highest pesticide residues included peppers, spinach, strawberries, celery,blueberries, potatoes, peaches, plums, apples and pears.

From Time: A Diet High in Pesticides Is Linked to a Lower Sperm Count

The troubling link between pesticide exposure and fertility isn’t new; scientists have already established that people who work with pesticides tend to have lower fertility than people who don’t. But for the majority of us who don’t work with chemicals, diet is the biggest source of exposure, says Jorge Chavarro, MD, assistant professor of nutrition and epidemiology at Harvard School of Public Health and senior author of a new study published in the journal Human Reproduction.

Chavarro and his colleagues wanted to see if pesticide residues left on fruits and vegetables might have a similar effect on sperm—and their findings suggest that they did. Men who ate fruits and vegetables with a lot of pesticides had lower sperm counts and more oddly shaped sperm than those who had lower levels of dietary pesticide exposure.

Over an 18-month period, the researchers used data from the Environment and Reproductive Health (EARTH) study, including semen samples from 155 men who were being treated at a Boston fertility clinic and a food frequency questionnaire they completed. The researchers determined pesticide exposure by comparing the questionnaire answers with government data about produce pesticide levels in the USDA’s Pesticide Data Program.

The study didn’t tease out individual foods, but the researchers classified produce according to whether it had high or low-to-moderate levels of pesticides. Men who ate the most high-pesticide fruits and vegetables had a 49% lower total sperm count and 32% fewer sperm that were shaped normally, compared to men who ate the least amount of the high-pesticide produce.

Researchers gave each piece of produce a score based on its level of detectable pesticides, its level of pesticides that exceeded the tolerance level established by the U.S. Environmental Protection Agency, and whether the produce had three or more types of detectable pesticides. (The bigger the score, the more it hit all three measures.) Ranked from highest pesticide contamination to lowest, here were the top fruits and vegetables: Green, yellow and red peppers (6), Spinach (6), Strawberries (6), Celery (6), Blueberries (5), Potatoes (5), Peaches and plums (5), Apples or pears (5), Winter squash (4), Kale, mustard greens and chard greens (4), Grapes and raisins (4).

The team didn’t tease out associations with individual pesticides. But they believe that a mixture of pesticides—not just one particular pesticide—is responsible for the link. The strongest variable in their analysis were the proportion of fruits and vegetables consumed that use three or more pesticides. “The more pesticides are applied on any particular crop, that seems to be having a bigger impact,” Chavarro says...But for people who are concerned about their dietary exposure to pesticides, there are ways to lower it, he says, like eating organic and choosing produce not listed on the Environmental Working Group’s dirty dozen list.

From Science  Daily: Pesticides in fruit and vegetables linked to semen quality

Assistant Professor of Nutrition and Epidemiology at the Harvard T.H. Chan School of Public Health in Boston (USA), Jorge Chavarro, said: "These findings should not discourage the consumption of fruit and vegetables in general. In fact, we found that total intake of fruit and vegetables was completely unrelated to semen quality. This suggests that implementing strategies specifically targeted at avoiding pesticide residues, such as consuming organically-grown produce or avoiding produce known to have large amounts of residues, may be the way to go."

There were no differences seen between men in the four groups who consumed fruit and vegetables with low-to-moderate pesticide residues. In fact, there was a significant trend towards having a higher percentage of normally shaped sperm among men who consumed the most fruit and vegetables with low pesticide residues -- a relative increase of 37% from 5.7% to 7.8%...Note:Pesticide use varies from country to country, but in the USA those used on fruit and vegetables include Atrazine, Malathion, Chlorpyrifos and Carbendazim. 

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More research showing health benefits of peanuts, including when eating them with a high fat meal. From Science Daily:

Adding peanuts to a meal benefits vascular health

A study of peanut consumption showed that including them as a part of a high fat meal improved the post-meal triglyceride response and preserved endothelial function.The purpose of this research was to evaluate vascular function after a high fat meal challenge.

Fifteen overweight males were randomized to either a peanut meal containing 3 oz. of ground peanuts (as a shake) or a control meal (a shake without peanuts) that were matched for energy and macronutrients...Flow-mediated dilatation (FMD) was measured to assess vascular function... The control meal decreased FMD by 1.2 percent compared to baseline. In contrast, there was no decrease in FMD after the peanut meal. These results demonstrate that the peanut meal maintained normal vascular function whereas the high fat-matched control meal impaired vascular function acutely.

Vascular dysfunction plays a major role in the development of atherosclerosis and the formation of coronary plaques and lesions that lead to coronary artery disease. Typically after a high fat meal, vascular function is reduced, albeit temporarily, until the fat that is in the blood (from the meal) is cleared. Strategies that can blunt this response to both dietary fat and its effect on vascular dysfunction may decrease the risk of coronary disease. Our finding demonstrated that that peanut consumption was shown to be atheroprotective as a part of high fat meal.

"Previous studies have shown that individuals who consume peanuts more than two times a week have a lower risk of coronary heart disease," said Liu. "This study indicates that the protective effect of peanut consumption could be due, in part, to its beneficial effect on artery health."

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The American diet with its emphasis on highly processed foods is linked to chronic diseases. It's also not healthy when you look at the microbiome (community of microbes living in your body). With all the health research out there showing health benefits of real whole foods (especially fruits, vegetables, whole grains, seeds, legumes), then the finding that highly processed foods dominate U.S. food purchases are just plain sad. But I'm not surprised. From Science Daily:

Highly processed foods dominate U. S. grocery purchases

A nation-wide analysis of U.S. grocery purchases reveals that highly processed foods make up more than 60 percent of the calories in food we buy, and these items tend to have more fat, sugar and salt than less-processed foods.

From 2000 to 2012, the researchers asked 157,142 households to use UPC barcode scanners to record all foods and beverages they purchased from grocery stores for at least 1 year. Although items without barcodes were not included, Poti points out that packaged produce such bagged lettuce or pints of berries can be scanned. Households participated in the study for an average of four years and collectively purchased 1.2 million items. The research team then linked each item to its nutrition information, product description and ingredient list, allowing them to rank each product's degree of food processing.

The researchers classified products as highly processed if they contained multi-ingredient, industrially formulated mixtures. They labeled foods such as soda, cookies, chips, white bread, candy and prepared meals as highly processed foods and categorized fresh or frozen fruits and vegetables, milk, eggs, dried beans and fresh meat as unprocessed or minimally processed. The investigators also examined convenience, distinguishing between foods that are ready to eat, ready to heat or require cooking and/or preparation. Candy and chips are examples of ready-to-eat foods, and frozen meals are a ready-to-heat food.

"Overall, we found that not only are highly processed foods a dominant, stable part of U.S. purchasing patterns, but also that the highly-processed foods that households are purchasing are higher in fat, sugar, and salt, on average, compared to the less-processed foods that they buy," said Poti, who will present these findings at the American Society for Nutrition (ASN) Annual Meeting during Experimental Biology 2015."

The analysis revealed that from 2000 to 2012, the proportion of calories in highly processed food and beverage purchases by U.S. households remained stable at 61.0 to 62.5 percent. The researchers noted a significant increase in the proportion of calories purchased in ready-to-heat foods, which reached 15.2 percent in 2012. More than 80 percent of calories were purchased in ready-to-eat or ready-to-heat form in 2012, and these tended to be higher in fat, sugar and salt than food purchases that required preparation.

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Discussions of the benefits of dietary fiber seem to be everywhere this week.

From Forbes: Eat Whole Grains For A Long Life, New Study Says

Eating lots of whole grains – especially those high in cereal fiber – may help people live longer, according to new research. The study out in BMC Medicine this week suggests that eating hefty amounts of cereal fibers can help reduce the risk of death from a number of causes, including cancer and diabetes, by almost 20%. Previous research has certainly linked whole grains to the reduction of certain chronic diseases and to reduced mortality, but this one is the largest of its kind to show a reduction in death from a number of different causes. So if you want to live longer, grab a bowl of cereal. The less refined, the better.

Whole grains are grains in their most unadulterated form, still containing the endosperm, bran, and germ – most of the plant’s nutritional value lies in the bran and germ. When grains go through milling to become processed or refined, they’re typically stripped of the bran and germ parts, along with a number of B vitamins, fiber, and iron.

In the new study, the Harvard Medical School team tracked over 367,000 healthy people who were taking part in the NIH-AARP Diet and Health Study, for an average of 14 years. ..It turned out that people who ate more whole grains – 1.2 ounces of per day, on average – had a 17% reduced risk of death, compared to those who ate much less, around 0.13 ounces per day. And when it came to the cereal fiber itself, people who ate the most had a 19% reduced risk of death from any cause, compared to those who ate the least.

The researchers even broke it down by disease: People who ate the highest amounts of whole grains had a 48% reduced risk of death from diabetes, and an 11% reduced risk of dying from respiratory diseases. And people who ate the most cereal fiber had 15% and 34% reduced risk of death from cancer and diabetes, respectively. 

The study cannot of course determine causation, since it’s just observational...Still, a number of studies have pointed to a strong connection between whole grains and improved health and longevity in recent years. It may be the anti-inflammatory properties of fiber per se – and its effect of reducing c-reactive protein (CRP) and tumor necrosis factor – that are responsible for their health benefits. If you’re going to up your grain intake, make sure to choose whole ones, like steel cut oats, quinoa, or even whole grain bread, over refined ones like cereal flakes or white bread. 

From Scientific American: Fiber-Famished Gut Microbes Linked to Poor Health

Your gut is the site of constant turf wars. Hundreds of bacterial species—along with fungi, archaea and viruses—do battle daily, competing for resources. Some companies advocate for consuming more probiotics, live beneficial bacteria, to improve microbial communities in our gut, but more and more research supports the idea that the most powerful approach might be to better feed the good bacteria we already harbor. Their meal of choice? Fiber.  

Fiber has long been linked to better health, but new research shows how the gut microbiota might play a role in this pattern. One investigation discovered that adding more fiber to the diet can trigger a shift from a microbial profile linked to obesity to one correlated with a leaner physique. Another recent study shows that when microbes are starved of fiber, they can start to feed on the protective mucus lining of the gut, possibly triggering inflammation and disease.

"Diet is one of the most powerful tools we have for changing the microbiota," Justin Sonnenburg, a biologist at Stanford University, said earlier this month at a Keystone Symposia conference on the gut microbiome. "Dietary fiber and diversity of the microbiota complement each other for better health outcomes." In particular, beneficial microbes feast on fermentable fibers—which can come from various vegetables, whole grains and other foods—that resist digestion by human-made enzymes as they travel down the digestive tract. These fibers arrive in the large intestine relatively intact, ready to be devoured by our microbial multitudes. Microbes can extract the fiber's extra energy, nutrients, vitamins and other compounds for us. Short-chain fatty acids obtained from fiber are of particular interest, as they have been linked to improved immune function, decreased inflammation and protection against obesity.

Today's Western diet, however, is exceedingly fiber-poor by historical standards. It contains roughly 15 grams of fiber daily, Sonnenburg noted. For most of our early history as hunter-gatherers, we were likely eating close to 10 times that amount of fiber each day. "Imagine the effect that has on our microbiota over the course of our evolution," he said.

Not all helpful fiber, however, needs to come from the roots and roughage for which our ancestors foraged, new research suggests. Kelly Swanson, a professor of comparative nutrition at the University of Illinois at Urbana-Champaign, and his team found that simply adding a fiber-enriched snack bar to subjects' daily diets could swing microbial profiles in a matter of weeks... The findings were published in the January issue of the American Journal of Clinical Nutrition.

As gut microbes are starved of fermentable fiber, some do die off. Others, however, are able to switch to another food source in the gut: the mucus lining that helps keep the gut wall intact and free from infection. In a recent study presented at the Keystone meeting, Eric Martens of the University of Michigan Medical School, postdoctoral researcher Mahesh Desai and their colleagues found that this fuel switch had striking consequences in rodents. A group of mice fed a high-fiber diet had healthy gut lining, but for mice on a fiber-free diet, "the mucus layer becomes dramatically diminished," he explained at the meeting. This shift might sometimes have severe health consequences. Research by a Swedish team, published last year in the journal Gut, showed a link between bacteria penetrating the mucus layer and ulcerative colitis, a painful chronic bowel disease.

A third group of mice received high-fiber chow and fiber-free chow on alternating days—"like what we would do if we were being bad and eating McDonald's one day and eating our whole grains the next," Martens joked. Even the part-time high-fiber diet was not enough to keep guts healthy: these mice had a mucus layer about half the thickness of mice on the consistently high-fiber diet. If we can extend these results to humans, he said, it "tells us that even eating your whole fiber foods every other day is still not enough to protect you. You need to eat a high-fiber diet every day to keep a healthy gut." Along the same lines, Swanson's group found that the gut microbiomes of his adult subjects reverted back to initial profiles as soon as the high-fiber bars were discontinued.