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This research review suggests that 5 servings a day of fruits and vegetables has the best health benefits. They surprisingly did not find that fruit/vegetable consumption was protective against cancer. But the authors point out that other studies of cancer and fruit/vegetable consumption have also been inconsistent, and this might be partly explained if certain fruits and vegetables only have effects on certain cancers. From Medical Daily:

An Apple A Day Keeps The Doctor Away? Actually It's 5 Apples, And They Keep Death Away

A review of the eating habits of more than 800,000 people seems to discredit the old maxim about "an apple a day." In fact, five servings of fruit and vegetables offers the best health benefits, particularly against heart disease, and reduces your chances of dying for any reason.

After calculating the odds, researchers write in the Journal of Epidemiology and Community Health that "the risk of all-cause mortality was decreased by 5 percent for each additional serving a day of fruit and vegetables." But, contrary to other reports, they found the benefits drop off after five servings, at which point, they wrote, "we observed a threshold." Previous studies have said seven fruit and vegetable servings is the optimum number.

Other studies have also made the case for fruits and vegetables as a ward against cancer. This one, led by Professor Frank B. Hu in the Harvard School of Public Health, saw no evidence for that. They did, however, find a "significant inverse association" between a fruit and veggie diet and death by heart disease. "The results support current recommendations to increase consumption to promote health and overall longevity," Hu and his colleagues wrote.

Of course, the authors admit, the studies they looked at may have been corrupted by participants lying or guessing on their diet questionnaires. But one thing this study has going for it is the massive sample size. They looked at 16 papers involving 833,234 people and 56,423 deaths. Most of those deaths — as is the case in the general population — were caused by cardiovascular disease and cancer. The people who lived longest adhered to what's called the Mediterranean diet, which favors carrots and tomatoes to steak and bacon.

Two related articles, the first from a month ago, but both discuss eating fresh foods of summer and the effect on the microbiota. From Gut Microbiota Worldwatch:

Seasonal diet changes affect the composition of our gut microbiota

The mix of bacteria that live in our gut changes throughout the year, to match the food we eat in every specific season. For example, bacteria that process fresh fruit and vegetables are more abundant in the summer, and those that process fats are mode abundant in winter times. A group of scientists at the University of Chicago has found evidence of this seasonal shift in the gut flora, by studying the remote Hutterite population, in North America. The traditional diet and common meals of this community have allowed researchers to study the effect of one common diet in a large population over a long period of time.

Hutterites live in communal farms (colonies) and eat meals in common dining rooms, using traditional recipes that have been relatively stable over time and between colonies. They have little contact with the world outside their colonies, which translates into a very homogeneous genetic pool. Sixty Hutterites from six colonies answered questionnaires about what they ate over the course of a year. During the same period, scientists sampled their stool periodically, to find the genetic sequences of bacteria contained in their gut.

The Hutterites’ diet is relatively stable, except that in summer they eat more fresh fruit and vegetables, and in winter they eat less, and turn to frozen or canned food. Remarkably, their gut flora responded to these changes with massive modification in the abundance of certain bacteria. For example, during summer Bacteroidetes were more abundant: this group of bacteria contain complex carbohydrate digesters, which may be at work in processing fresh fruit and vegetables.

On the other hand Actinobacteria increased in winter: these microbes are associated with processing fat, and with a decreased content of fibre in food. Researchers also found seasonal shifts in other types of bacteria, whose associations with food are still unknown. Notably, the trends were almost identical in all six colonies, possibly a result of a very homogenous lifestyle carried on in a very similar environment.

Although Hutterites live in a relatively isolated way, they use technology and medicine, which makes their lifestyle closer to the general population than that of other more traditional communities. That is why the authors believe that these results may be extended to the general population.

This healthy living article promotes eating fresh fruits and vegetables (tomatoes, blueberries, asparagus, and leeks) as good for the gut microbiome. From Huffington Post:

4 Summer Foods That Can Help Trim Your Waist

Future microbiome research and therapy will have to take into account that diet affects the gut microbes of men and women differently. From Science Daily:

Diet affects males' and females' gut microbes differently

The microbes living in the guts of males and females react differently to diet, even when the diets are identical, according to a new study. These results suggest that therapies designed to improve human health and treat diseases through nutrition might need to be tailored for each sex.

The researchers studied the gut microbes in two species of fish and in mice, and also conducted an in-depth analysis of data that other researchers collected on humans. They found that in fish and humans diet affected the microbiota of males and females differently. In some cases, different species of microbes would dominate, while in others, the diversity of bacteria would be higher in one sex than the other.

These results suggest that any therapies designed to improve human health through diet should take into account whether the patient is male or female.

Genetics and diet can affect the variety and number of these microbes in the human gut, which can in turn have a profound influence on human health. Obesity, diabetes, and inflammatory bowel disease have all been linked to low diversity of bacteria in the human gut.

Why men and women would react differently to changes in diet is unclear, but there are a couple of possibilities. The hormones associated with each sex could potentially influence gut microbes, favoring one strain over another. Also, the sexes often differ in how their immune systems function, which could affect which microbes live and die in the microbiome.

One notable exception in Bolnick's results was in the mice. Although there was a tiny difference between male and female mice, for the most part the microbiota of each sex reacted to diet in the same manner. Because most dietary studies are conducted on mice, this result could have a huge effect on such research, and it raises questions about how well studies of gut microbes in lab mice can be generalized to other species, particularly humans.

This research illustrates how little we currently know about gut bacteria.But it did show the importance of diet. From Science Daily:

Monitoring rise and fall of the microbiome

Trillions of bacteria live in each person's digestive tract. Scientists believe that some of these bacteria help digest food and stave off harmful infections, but their role in human health is not well understood.

To help shed light on the role of these bacteria, a team of researchers led by MIT associate professor Eric Alm recently tracked fluctuations in the bacterial populations of two research subjects over a full year. The findings, described in the July 25 issue of the journal Genome Biology, suggest that while these populations are fairly stable, they undergo daily fluctuations in response to changes in diet and other factors...."To a large extent, the main factor we found that explained a lot of that variance was the diet."

There are a few thousand strains of bacteria that can inhabit the human gut, but only a few hundred of those are found in any given individual, Alm says. For one year, the two subjects in the study collected daily stool samples so bacterial populations could be measured. They also used an iPhone app to track lifestyle factors such as diet, sleep, mood, and exercise, generating a huge amount of data.

Analysis of this data revealed that dietary changes could produce daily variations in the populations of different strains of bacteria. For example, an increase in fiber correlated with a boost in the populations of Bifidobacteria, Roseburia, and Eubacterium rectale. Four strains -- including Faecalibacterium prausnitzii, which has been implicated in protecting against inflammatory bowel disease -- were correlated with eating citrus.

During the study, each of the two subjects experienced an event that dramatically altered the gut microbiome. Subject B experienced food poisoning caused by Salmonella, and Subject A traveled to a developing nation, where he experienced diarrheal illness for two weeks.

During Subject B's infection, Salmonella leapt from 10 percent of the gut microbiome to nearly 30 percent. At the same time, populations of bacteria from the phylum Firmicutes, believed to be beneficial to human health, nearly disappeared. After the subject recovered, Firmicutes rebounded to about 40 percent of the total microbiome, but most of the strains were different from those originally present.

Subject A also exhibited severe disruptions to his microbiome during his trip, but once he returned to the United States, it returned to normal. Unlike Subject B's recovery from food poisoning, Subject A's populations returned to their original composition.

Great reason to add more rosemary and oregano to your diet. From Science Daily:

Rosemary, oregano contain diabetes-fighting compounds

The popular culinary herbs oregano and rosemary are packed with healthful compounds, and now lab tests show they could work in much the same way as prescription anti-diabetic medication, scientists report. In their new study, researchers found that how the herbs are grown makes a difference, and they also identified which compounds contribute the most to this promising trait.

Elvira Gonzalez de Mejia and colleagues point out that in 2012, type-2 diabetes affected more than 8 percent of Americans and cost the country $175 billion. ... Recent research has shown that herbs could provide a natural way to help lower glucose in blood. So Gonzalez de Mejia's team decided to take a closer look.They tested four different herbs, either greenhouse-grown or dried commercial versions, for their ability to interfere with a diabetes-related enzyme, which is also a target of a prescription drug for the disease.

They found that greenhouse herbs contained more polyphenols and flavonoids compared to the equivalent commercial herbs. But this didn't affect the concentration required to inhibit the enzyme. Commercial extracts of Greek oregano, Mexican oregano and rosemary were better inhibitors of the enzyme, required to reduce risk of type-2 diabetes, than greenhouse-grown herbs.

Even though it looks to be a modest effect, it is still good news. But they should have added kefir to the list of probiotic containing foods. From Science Daily:

Eating probiotics regularly may improve your blood pressure

Eating probiotics regularly may modestly improve your blood pressure, according to new research in the American Heart Association journal  Hypertension. Probiotics are live microorganisms (naturally occurring bacteria in the gut) thought to have beneficial effects; common sources are yogurt or dietary supplements.

"The small collection of studies we looked at suggest regular consumption of probiotics can be part of a healthy lifestyle to help reduce high blood pressure, as well as maintain healthy blood pressure levels," said Jing Sun, Ph.D., lead author and senior lecturer at the Griffith Health Institute and School of Medicine, Griffith University, Gold Coast, Queensland, Australia. "This includes probiotics in yogurt, fermented and sour milk and cheese, and probiotic supplements."

Analyzing results of nine high-quality studies examining blood pressure and probiotic consumption in 543 adults with normal and elevated blood pressure, researchers found:

  • Probiotic consumption lowered systolic blood pressure (the top number) by an average 3.56 millimeters of mercury (mm Hg) and diastolic blood pressure (the lower number) by an average 2.38 mm Hg, compared to adults who didn't consume probiotics.
  • The positive effects from probiotics on diastolic blood pressure were greatest in people whose blood pressure was equal to or greater than 130/85, which is considered elevated.
  • Probiotics with multiple bacteria lowered blood pressure more than those with a single bacteria.

We believe probiotics might help lower blood pressure by having other positive effects on health, including improving total cholesterol and low-density lipoprotein, or LDL, cholesterol; reducing blood glucose and insulin resistance; and by helping to regulate the hormone system that regulates blood pressure and fluid balance," Sun said.

After posting yesterday "Probiotic Misconceptions", I was pleasantly surprised that today's NY Times had an article (by Jane Brody) raising similar concerns. What was good is that she wrote about supplements not being regulated. She also left out that probiotic beneficial organisms are found in more than the gut. A case in point being the sinuses - because healthy sinuses also have Lactobacillus sakei (according to the Abreu et al study of 2012), and which has been the basis for my family's successful kimchi treatment for sinusitis (see Sinusitis treatment link for the method). From the NY Times:

Probiotic Logic vs. Gut Feelings

The label on my bottle of Nature’s Bounty Advanced Probiotic 10 says it contains 10 probiotic strains and 20 billion live cultures in each two-capsule dose. The supplement provides “advanced support for digestive and intestinal health” and “healthy immune function.” I have no way to know if any of this is true. Like all over-the-counter dietary supplements, probiotics undergo no premarket screening for safety, effectiveness or even truth in packaging. 

To be sure, lay and scientific literature are filled with probiotic promise, and I am hardly the only consumer who has opted to hedge her bets. The global market for probiotic supplements and foods is expected to reach $32.6 billion this year,with a projected annual growth of 20 percent or more.

 Beneficial micro-organisms have since been shown to inhabit three main locations in the digestive tract: the stomach, the lower part of the small intestine and the large intestine. To better understand the current enthusiasm for enhancing the body’s supply of these micro-organisms, some definitions are needed.

Prebiotics are nondigestible carbohydrates that stimulate the growth and activity of beneficial micro-organisms (that is, probiotics) in the gut. They are found naturally in oats, wheat, some fruits and vegetables (bananas, onions, garlic, leeks, asparagus, soybeans, honey and artichokes), and in breast milk, and they are added to some infant formulas.

Probiotics are defined by the World Health Organization as “live micro-organisms which when administered in adequate amounts confer a health benefit on the host.” The ailments that probiotics are said to benefit range from infection-caused diarrhea, inflammatory bowel diseases and irritable bowel syndrome to asthma, allergy and Type 1 diabetes.

Synbiotics are a combination of prebiotics and probiotics. They are found in so-called functional foods like yogurt and kefir, fermented foods like pickles and some cheeses, and in some supplements.

That probiotic organisms are important to health is not questioned. As researchers at the Institute for Immunology at the University of California,Irvine have written intestinal micro-organisms play “an important role in the development of the gut immune system, digestion of food, production of short-chain fatty acids and essential vitamins, and resistance to colonization from pathogenic microorganisms.”

Dr. Walker has explained that probiotics enhance defensive action by the cells that line the gut. When a person takes antibiotics, especially the broad-spectrum antibiotics most often prescribed, many of these beneficial microbes are destroyed along with the disease-causing bacteria. Patients on antibiotics are often told to consume yogurt with active cultures to replenish the beneficial organisms.

In an extensive review of the evidence published in 2010 in the journal Pediatrics, an expert committee concluded that probiotics might limit the course of virus-caused diarrhea in otherwise healthy infants and children. But the committee said there was not sufficient evidence to justify routine use of probiotics to prevent rotavirus-caused diarrhea in child care centers. Nor did the committee endorse taking probiotics during pregnancy and nursing or giving them to infants to prevent allergic disorders in those at risk.

Only a small percentage of probiotic foods and supplements have the backing of peer-reviewed published research. They include Dannon’s Activia yogurt and DanActive drink and the supplements Culturelle and Align. Although kefir contains even more probiotic strains than yogurt, clinical studies have not shown it to be effective in preventing or treating infectious diarrhea.

The challenge in taking probiotics is to get the microbes past the stomach, where most are killed by gastric acid, said Robert Dunn, a biologist at North Carolina State University. Once in the intestines, they must compete effectively with the microbes already present.

Dr. Dunn, author of "The Wild Life of Our Bodies," says there is good reason to remain skeptical of probiotics“There are hundreds of kinds of prebiotics and probiotics in stores,” he said. “As a consumer, it’s almost impossible to figure out what is best. What are the specific species in your intestines, and how will what you take compete with them?” Still, he added, taking them doesn’t seem harmful. 

There is growing evidence for the role of the appendix in restoring a healthful balance of microbes in the body. Though long considered an expendable, vestigial organ, the appendix is now being looked at as “a storehouse of good bacteria,” Dr. Dunn said. In a study of recovery rates from Clostridium difficile, which causes a severe form of infectious diarrhea, often following antibiotic therapy, patients whose appendixes had been removed were more likely to have a recurrent infection than those who still had appendixes.

I keep overhearing misguided statements like these all the time: that somehow any and all probiotic (beneficial) bacteria offered for sale, whether in foods such as yogurt, or in probiotic capsules, are wonderful and beneficial, and will reseed your gut as well as do all sorts of miraculous things for your health. And while in reality, there are many, many bacterial species living in a healthy person's gut, it's the same few species that seem to be offered everywhere.

But if you look at the scientific research for even a few minutes, you realize that NO, we actually know very little about the health benefits of these bacteria species now in stores, and that all the claims out there don't have evidence backing them up. Perhaps taking megadoses of certain bacteria even has some negative effects. Yes, Lactobacillus species are generally considered beneficial by scientists. But even in the Lactobacillus family, there are many more types than the few now available in stores. For example. I can not find Lactobacillus sakei (which is found in kimchi and we use to successfully treat sinusitis - see Sinusitis Treatment link) in any store at this time.

Another problem is that sometimes you don't even get the desired bacteria that has been added to the food or cosmetic. For example, this occurs when some Lactobacillus or other bacteria are added to yogurt or some other food, but then the food is pasteurized, which kills off the bacteria. Duh...This is why I liked the following  opinion piece by Julianne Wyrick. From Scientific American:

Are probiotics helping you?

Consuming probiotics – also know as “good” bacteria – via supplements or yogurt has been popularized as a way to maintain gut health. While taking a daily dose of probiotics may not be harming you, it also may not be helping. The idea that every probiotic is good for every disease or condition is oversimplified, according to Catherine Lozupone, an assistant professor of medicine at the University of Colorado School of Medicine.

Lozupone spoke on a panel about the human microbiome, or the bacteria that reside in and on our bodies, that I attended at the Association of Health Care Journalists Conference last month. The panel touched on misconceptions related to probiotics, so I gave Lozupone a call post-conference to learn more.

One misconception Lozupone brought up was the idea that probiotic supplements should be used for “reseeding the good bacteria” missing in a person’s gut. Probiotic supplements often only contain a few species of bacteria, whereas a healthy gut generally has hundreds of species. In addition, the microbes that are abundant in a healthy gut are often different than those found in many supplements. A healthy gut is mostly composed of bacterial species that fall within a two different groups of bacteria: the phyla Bacteroidetes and Firmicutes. One group of bacteria commonly found in probiotics is known as Lactobacillus. While Lactobacillus is a type of Firmicute, it isn’t a type of Firmicute that is typically found in great abundance in a healthy adult gut, according to Lozupone. While Lactobacillus may be helpful for some people in some situations, the idea that everyone needs to repopulate their gut with this “good” bacteria is an overgeneralization.

“I think probiotics have a ton of potential, but different bacteria are going to do different things in different contexts,” Lozupone said. “This notion [of] ‘oh just reseed the good bacteria … they’re good for you’ is definitely very oversimplified.”

But while some general probiotic health claims are ahead of the research, studies do suggest that particular types of probiotic bacteria have potential for specific uses.

For example, Lozupone noted some rodent studies suggest certain microbes might mitigate certain effects of a high-fat diet, which could be helpful to treating obesity and associated health problems.

“There’s just lots of different contexts where the microbiome has been shown to be important,” Lozupone said. Going forward, researchers hope to not only find microbes that have health effects, but also understand why they have these effects. If you’re interested in keeping track of the current research into our body’s bacteria, keep your eye on the NIH’s Human Microbiome Project, an international effort to study the role of the body’s bacteria in our health.

The study found real differences between organic and conventionally grown foods - organic foods have lower levels of pesticides, higher levels of antioxidants, and lower levels of cadmium. From NY Times:

Study of Organic Crops Finds Fewer Pesticides and More Antioxidants

Adding fuel to the debates over the merits of organic fooda comprehensive review of earlier studies found substantially higher levels of antioxidants and lower levels of pesticides in organic fruits, vegetables and grains compared with conventionally grown produce.

However, the full findings, to be published next week in the British Journal of Nutrition, stop short of claiming that eating organic produce will lead to better health. Still, the authors note that other studies have suggested some of the antioxidants have been linked to a lower risk of cancer and other diseases.

Organic farming, by and large, eliminates the use of conventional chemical fertilizers and pesticides. Those practices offer ecological benefits like healthier soils but produce less bountiful harvests. 

In the new study, an international team of scientists did not conduct any laboratory or field work of their own. Instead, they compiled a database from 343 previously published studies and performed a statistical procedure known as a meta-analysis, which attempts to ferret robust bits of information from studies of varying designs and quality.

Over all, organic crops contained 17 percent more antioxidants than conventionally grown crops, the new study found. For some classes of antioxidants, the difference was larger. A group of compounds known as flavanones, for example, were 69 percent higher in the organic produce. (At very high quantities, as in some supplements, some antioxidants have been shown to be harmful, but the levels in organic produce were not nearly that high.)

The researchers said they analyzed the data in several different ways, and each time the general results remained robust. Charles M. Benbrook, a professor at Washington State University and another author of the paper, said this analysis improved on earlier reviews, in part because it incorporated recent new studies.

The study also found that organically produced foods, particularly grains, contain lower levels of cadmium, a toxic metal that sometimes contaminates conventional fertilizers. Dr. Benbrook said the researchers were surprised by that finding; there was no difference in other toxic metals like mercury and lead.

This is Part 2 on how lifestyle influences aging. Many recent research reports tell of a link between our lifestyle and how we'll age - whether we'll be active and healthy well into our 80s or in terrible shape and dying young. Mind you, these are not "definites" because nothing can give you a guarantee, but they are ways we can improve our odds in living the long and healthy life that we want. From February 2014 Medscape:

Cancers Caused by Lifestyle Behaviors: Experts Urge Action

In launching the World Cancer Report 2014 earlier this week, the editors emphasized the need for prevention and highlighted lifestyle behaviors that lead to cancer, including smoking tobacco, drinking alcohol, overweight/obesity, and lack of exerciseThe report, issued by the International Agency for Research on Cancer (IACR), contains contributions from more than 250 scientists worldwide, many of them leading experts in their fields. 

In the United States, 1 in 3 cancer deaths is related to obesity, poor nutrition, or physical inactivity, and the problem will only increase as more countries and regions adopt the diet and lifestyles of more economically developed economies."

Tobacco, both smoked and smokeless, remains the world's leading cause of cancer morbidity and mortality, the report notes. The IACR and also the US Surgeon General have concluded that the relationship with smoking is causal for cancers of the nasal and oral cavities, hypopharynx, larynx, trachea, esophagus, lung, bronchus, bone marrow (leukemia), stomach, kidney, pancreas, ureter, uterus, bladder, and cervix. The IACR expands this list to also include paranasal sinuses, liver, colon, rectum, and ovary (mucinous), but says it is unclear if there is a link with breast cancer.

Still under-recognized, and not acted on, is the association between drinking alcohol and cancer. The agency says cancers caused by drinking alcoholic beverages include those of the oral cavity, pharynx, larynx, esophagus, liver, colorectum, and female breast.

Excess body fat increases the risk for cancers of the esophagus, colon, pancreas, endometrium, and kidney, as well as postmenopausal breast cancer. The evidence for obesity increasing the risk for these cancers is "convincing," the agency comments, and there is a dose–response relationship, so being overweight is less risky than being obese.

Regular physical activity reduces the risk for multiple cancers by contributing to weight control, and also reduces the risk for colorectal and breast cancer by additional mechanisms. The general consensus among researchers is that exercise should be of moderate intensity and average at least an hour each day.

High consumption of red meat, especially processed meat, is associated with a risk for colorectal cancer. "A diet high in fruit and vegetables and whole grains does not appear to be as strongly protective against cancer as initially believed," the report notes. "However, this dietary pattern is still advisable because of the benefits for diabetes and cardiovascular diseases, and some possible reductions in cancer incidence."

From Science Daily:

Watching too much TV may increase risk of early death: Three hours a day linked to premature death from any cause

Adults who watch TV three hours or more a day may double their risk of premature death from any cause. Researchers suggest adults should consider getting regular exercise, avoiding long sedentary periods and reducing TV viewing to one to two hours a day.

Results of a large study published in the Mayo Clinic Proceedings. From Science Daily:

Large waist linked to poor health, even among those in healthy body mass index ranges

Having a big belly has consequences beyond trouble squeezing into your pants. It’s detrimental to your health, even if you have a healthy body mass index (BMI), a new international collaborative study has found. Men and women with large waist circumferences were more likely to die younger, and were more likely to die from illnesses such as heart disease, respiratory problems, and cancer after accounting for body mass index, smoking, alcohol use and physical activity.

Some good news for those who have to sit for long periods every day at work - being physically fit may help. From Science Daily:

Physical fitness associated with less pronounced effect of sedentary behavior

Physical fitness may buffer some of the adverse health effects of too much sitting, according to a new study. Sedentary behavior has been linked to an increase risk of obesity, metabolic syndrome, type 2 diabetes mellitus, cardiovascular disease, some cancers, and premature death. But previous studies of the association have not taken into account the protective impact of fitness, a strong predictor of cardiovascular disease incidence and mortality.