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Category: healthy living

Published on Leave a comment on Lots of Diverse Bacteria On Fresh Produce

 There has been tremendous concern in recent years over pathogenic bacteria (such as Salmonella and Escherichia coli) found on raw fruits and vegetables. But what about nonpathogenic bacteria? Aren't some of the benefits of eating raw fruits and vegetables the microbes found on them? What actually is on them?

The following research using modern genetic analysis (16 S rRNA gene pyrosequencing) is from 2013, but very informative and the only study that I could find of its kind. The results suggest that humans are exposed to substantially different bacteria depending on the types of fresh produce they consume, with differences between conventionally and organically farmed varieties contributing to this variation.

While each of the 11 produce types studies harbored different microbial communities, the most common (abundant) across all samples were: Enterobacteriaceae [30% (mean)], Bacillaceae (4.6%), and Oxalobacteraceae (4.0%). Earlier studies also suggested that non-pathogenic microbes may interact with and inhibit microbial pathogens found on produce surfaces. Bottom line: eat a variety of raw fruits and vegetables to get exposed to a variety of non pathogenic microbes.

From Science Daily: Diverse bacteria on fresh fruits, vegetables vary with produce type, farming practices

Fresh fruit and vegetables carry an abundance of bacteria on their surfaces, not all of which cause disease. In the first study to assess the variety of these non-pathogenic bacteria, scientists report that these surface bacteria vary depending on the type of produce and cultivation practices. The results are published March 27 in the open access journal PLOS ONE by Jonathan Leff and Noah Fierer at the University of Colorado, Boulder.

The study focused on eleven produce types that are often consumed raw, and found that certain species like spinach, tomatoes and strawberries have similar surface bacteria, with the majority of these microbes belonging to one family. Fruit like apples, peaches and grapes have more variable surface bacterial communities from three or four different groups. The authors also found differences in surface bacteria between produce grown using different farming practices.

The authors suggest several factors that may contribute to the differences they observed, including farm locations, storage temperature or time, and transport conditions. These surface bacteria on produce can impact the rate at which food spoils, and may be the source of typical microbes on kitchen surfaces. Previous studies have shown that although such microbes don't necessarily cause disease, they may still interact with, and perhaps inhibit the growth of disease-causing microbes. The results of this new research suggest that people may be exposed to substantially different bacteria depending on the types of produce they consume.

Excerpts of the actual study from PLoS One:  Bacterial Communities Associated with the Surfaces of Fresh Fruits and Vegetables

Fresh fruits and vegetables can harbor large and diverse populations of bacteria. However, most of the work on produce-associated bacteria has focused on a relatively small number of pathogenic bacteria....Our results demonstrated that the fruits and vegetables harbored diverse bacterial communities, and the communities on each produce type were significantly distinct from one another. However, certain produce types (i.e., sprouts, spinach, lettuce, tomatoes, peppers, and strawberries) tended to share more similar communities as they all had high relative abundances of taxa belonging to the family Enterobacteriaceae when compared to the other produce types (i.e., apples, peaches, grapes, and mushrooms) which were dominated by taxa belonging to the Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria phyla. ...Taken together, our results suggest that humans are exposed to substantially different bacteria depending on the types of fresh produce they consume with differences between conventionally and organically farmed varieties contributing to this variation.

Fresh produce, including apples, grapes, lettuce, peaches, peppers, spinach, sprouts, and tomatoes, are known to harbor large bacterial populations [1]–[7], but we are only just beginning to explore the diversity of these produce-associated communities. We do know that important human pathogens can be associated with produce (e.g., L. monocytogenes, E. coli, Salmonella), and since fresh produce is often consumed raw, such pathogens can cause widespread disease outbreaks [8]–[11]. In addition to directly causing disease, those microbes found in produce may have other, less direct, impacts on human health. Exposure to non-pathogenic microbes associated with plants may influence the development of allergies [12],and the consumption of raw produce may represent an important means by which new lineages of commensal bacteria are introduced into the human gastrointestinal system. 

Although variable, taxonomic richness levels differed among the eleven produce types with richness being highest on peaches, alfalfa sprouts, apples, peppers, and mushrooms and lowest on bean sprouts and strawberries (Fig. 1). Bacterial communities were highly diverse regardless of the produce type with between 17 and 161 families being represented on the surfaces of each produce type. However, the majority of these families were rare; on average, only 3 to 13 families were represented by at least two sequences per produce type.

Furthermore, pairwise tests revealed that the community composition on the surface of each produce type differed significantly from one another. Still, certain produce types shared more similar community structure than others. On average, tree fruits (apples and peaches) tended to share communities that were more similar in composition than they were to those on other produce types, and produce typically grown closer to the soil surface (spinach, lettuce, tomatoes, and peppers) shared communities relatively similar in composition. Surface bacterial communities on grapes and mushrooms were each strongly dissimilar from the other produce types studied.

Published on Leave a comment on Forget the Pills, Eat the Vegetables Instead

An article that discusses why supplements containing large doses of antioxidants, or beta-carotene, or even vitamin megadoses  doesn't work, and can even cause harm, while eating actual foods such as fruits and vegetables has many health benefits. This is what a number of the studies I've been posting also found (especially with health benefits from eating fish and not from fish oil). go ahead and throw out the megadose supplements, and instead eat lots of fruits and vegetables. Remember fruits and vegetables contain a complex mix of nutrients and feed our microbial communities, as well as having microbes on them. From Medical Xpress:

Forget the antioxidant pills; just stick with veggies

Why just stick to eating fruits and veggies when you can get an extra boost from supplements that put good things like antioxidants into a handy pill? And that seems like it should be a good idea. If the antioxidants that occur naturally in our food, like broccoli and carrots, are good for us, a supplement with the same thing must also be good. But that's not quite true.

Antioxidants are touted as protectors of our health because they eliminate free-radicals that damage molecules in cells and tissues by grabbing electrons from them, making those molecules, in turn, unstable....On this basis, a group of scientists proposed in 1981 the creation of a nutritional supplement to fight free-radicals. They reasoned that since many observational epidemiological studies had shown that people who eat lots of vegetables are at lower risk of colon cancer, heart disease and many other bad conditions, then the "active" ingredient should be identified and put into a pill. They thought that it must be beta-carotene, which helps make carrots orange, because it's an antioxidant.

But in the late 1980s, two intervention trials, one in Seattle and the other in Finland, started....For the Seattle trial, approximately 18,000 men and women were randomized in 1988 to receive either a tablet containing beta-carotene or a tablet containing no active ingredient, which is the famous placebo. The plan was to follow the men and women for 10 years; the researchers hypothesized they would observe a lower lung cancer risk in the beta-carotene tablet group, hopefully much lower. But the opposite happened and the trial had to be stopped early because the beta-carotene group suffered significantly more cases of lung cancer than the placebo group. The same thing was seen in the Finland trial. Importantly, the amount of beta-carotene in the tablet was much higher than occurs naturally in the body in both trials.   ...continue reading "Forget the Pills, Eat the Vegetables Instead"

Published on Leave a comment on Meat is OK If You Also Eat Lots of Plant-Based Foods

 People have asked me if eating sweet desserts or hamburgers is bad for the health if the rest of their diet is good - with lots of fruits, vegetables, whole grains, legumes (beans), and nuts (much like the Mediterranean diet). My sense over the past few years of looking at the research is that one should look at the overall diet, and that a "perfect diet" all the time is pretty darn hard to achieve, if not impossible, for most of us. So this new research looking at gut bacteria and "chemical fingerprints of cellular processes" (by looking at stool and urine samples) of people eating different diets (vegan, vegetarian, omnivore) was reassuring.  The findings suggest: make sure to feed your beneficial bacteria with a healthy diet like the Mediterranean diet (lots of plant-based foods), and then some deviation (cookies! steak!) is OK.

The researchers found that while the kind of gut bacteria dominating were different among the groups (vegan, vegetarian, omnivores), they also found that eating a lot of fiber-rich foods, such as fruit, vegetables, and legumes (typical of a Mediterranean diet) is linked to a rise in health promoting short chain fatty acids (SCFA). Yes, levels of trimethylamine oxide (TMAO) (which is linked to cardiovascular disease) were significantly lower in vegetarians and vegans than they were in those of the omnivores. But the more omnivores closely followed a Mediterranean diet, the lower were their TMAO levels.(Which is great!). As the researchers said: "Western omnivore diets are not necessarily detrimental when a certain consumption level of plant foods is included. From Science Daily:

High dietary fiber intake linked to health promoting short chain fatty acids

Eating a lot of fibre-rich foods, such as fruit, vegetables, and legumes--typical of a Mediterranean diet--is linked to a rise in health promoting short chain fatty acids, finds research published online in the journal Gut. And you don't have to be a vegetarian or a vegan to reap the benefits, the findings suggest.

Short chain fatty acids (SCFAs), which include acetate, propionate, and butyrate, are produced by bacteria in the gut during fermentation of insoluble fibre from dietary plant matter. SCFAs have been linked to health promoting effects, including a reduced risk of inflammatory diseases, diabetes, and cardiovascular disease.

The researchers gathered a week's information on the typical daily diet of 153 adults who either ate everything (omnivores, 51), or were vegetarians (51), or vegans (51), and living in four geographically distant cities in Italy....The Mediterranean diet is characterised by high intake of fruit, vegetables, legumes, nuts and cereals; moderately high intake of fish; regular but moderate alcohol consumption; and low intake of saturated fat, red meat, and dairy products. Most (88%) of the vegans, almost two thirds of the vegetarians (65%), and around a third (30%) of the omnivores consistently ate a predominantly Mediterranean diet.

The investigation showed distinct patterns of microbial colonisation according to usual dietary intake. Bacteroidetes were more abundant in the stool samples of those who ate a predominantly plant based diet, while Firmicutes were more abundant in those who ate a predominantly animal products diet. Both these categories of organisms (phyla) contain microbial species that can break down complex carbohydrates, resulting in the production of SCFAs.

Specifically, Prevotella and Lachnospira were more common among the vegetarians and vegans while Streptococcus was more common among the omnivores. And higher levels of SCFA were found in vegans, vegetarians, and those who consistently followed a Mediterranean diet. Levels of SCFAs were also strongly associated with the quantity of fruit, vegetables, legumes, and fibre habitually consumed, irrespective of the type of diet normally eaten.

On the other hand, levels of trimethylamine oxide (TMAO)--a compound that has been linked to cardiovascular disease--were significantly lower in the urine samples of vegetarians and vegans than they were in those of the omnivores. But the more omnivores closely followed a Mediterranean diet, the lower were their TMAO levels, the analysis showed.

TMAO levels were linked to the prevalence of microbes associated with the intake of animal proteins and fat, including L-Ruminococcus (from the Lachnospiraceae family). Eggs, beef, pork and fish are the primary sources of carnitine and choline--compounds that are converted by gut microbes into trimethylamine, which is then processed by the liver and released into the circulation as TMAO.

The researchers point out that SCFA levels can naturally vary as a result of age and gender, and their study did not set out to establish any causal links. But they nevertheless suggest that the Mediterranean diet does seem to be associated with the production of health promoting SCFAs. They conclude: "We provide here tangible evidence of the impact of a healthy diet and a Mediterranean dietary pattern on gut microbiota and on the beneficial regulation of microbial metabolism towards health maintenance in the host." And they add: "Western omnivore diets are not necessarily detrimental when a certain consumption level of [plant] foods is included."

Published on Leave a comment on Missing Microbes in Infancy and Asthma

An interesting Canadian study that followed young children for 3 years found that young infants may be more likely to develop allergic asthma if they lack four beneficial bacteria in their gut. Children with low levels of Lachnospira, Veillonella, Faecalibacterium, and Rothia bacteria in their gut in their first 3 months were at higher risk for asthma and tended to receive more antibiotics than healthier children before they turned 1 year old.

Other studies have shown that the risk of developing asthma and allergies has been linked with such things as taking antibiotics, cesarean birth, bottle fed with formula, not living on a farm, and not having furry pets in the first year of life.

The researchers wrote: "Our findings indicate that in humans, the first 100 days of life represent an early-life critical window in which gut microbial dysbiosis {the microbial community being out of whack} is linked to the risk of asthma and allergic disease." How do the infants get these microbes? It is thought that infants get exposed to the mother's microbiome (microbial community) via vaginal birth, breast-milk, and mouth contact with the mother's skin.  From NPR News:

Missing Microbes Provide Clues About Asthma Risk

The composition of the microbes living in babies' guts appears to play a role in whether the children develop asthma later on, researchers reported Wednesday. The researchers sampled the microbes living in the digestive tracts of 319 babies, and followed up on the children to see if there was a relationship between their microbes and their risk for the breathing disorder. In the journal Science Translational Medicine, the researchers report Wednesday that those who had low levels of four bacteria were more likely to develop asthma by the time they were 3-years-old.

Specifically, the researchers focused on 22 children who showed early signs of asthma, such as wheezing, when they were 1-year-old. They were much more likely than the other children to have had low levels of the four bacteria when they were 3-months-old. By the time they turned 3, most had developed full-blown asthma."The bottom line is that if you have these four microbes in high levels you have a very low risk of getting asthma," says Brett Finlay, a microbiologist at the University of British Columbia who helped conduct the research. "If you don't have these four microbes or low levels of these microbes you have a much greater chance of asthma."

Asthma is a common and growing problem among children. Evidence has been accumulating that one reason may be a disruption in the healthful microbes children get early in life, Finlay says."There's all these smoking guns like, for example, if you breast-feed versus bottle feed you have less asthma," he says. "If you're born by C-section instead of vaginal birth you have a 20 percent higher rate of asthma. If you get antibiotics in the first year of life you have more asthma." The microbiomes of kids who aren't breast-fed and are born by Caesarean section may miss out on getting helpful bugs. Antibiotics can kill off the good bacteria that seem important for the development of healthy immune systems.

"What's become clear recently is that microbes play a major role in shaping how the immune system develops. And asthma is really an immune allergic-type reaction in the lungs," Finlay says. "And so our best guess is the way these microbes are working is they are influencing how our immune system is shaped really early in life."

To further test their theory, the researchers gave laboratory mice bred to have a condition resembling asthma in humans the four missing microbes. The intervention reduced the signs of levels of inflammation in their lungs, which is a risk factor for developing asthma.

The bacteria are from four genuses: Lachnospira, Veillonella, Faecalibacterium and Rothia. The researchers aren't exactly sure how the microbes may protect against asthma. But babies with few or none of them had low levels of a substance known as acetate, which is believed to be involved with regulating the immune system.

Published on Leave a comment on New Report About Harms of Endocrine Disruptors

A report released this week by the Endocrine Society states that the list of health problems that scientists can confidently link to exposure to hormone-disrupting chemicals has grown to include: diabetes, cardiovascular disease, obesity, reproductive and developmental problems, thyroid impairment, certain reproductive cancers, and neurodevelopmental problems such as decreased IQ. This statement (report) is based on the summaries of 1300 studies on endocrine disrupting chemicals (EDCs), and it also adds support to the idea that even minute doses of these chemicals can interfere with the activity of natural hormones, which play a major role in regulating physiology and behavior. The statement also stated that most industrial chemicals released into the environment—numbering in the tens of thousands—have never been tested for endocrine-disrupting potential. EDCs include such common chemicals as bisphenol A (BPA), phthalates, parabens, some pesticides (e.g., atrazine), flame retardants, some persistent organic pollutants, and dioxins.

Where are endocrine disruptors found? People are exposed to chemicals with estrogenic effects in their everyday life, because endocrine disrupting chemicals are found in low doses in thousands of products. Many plastic products, including those advertised as "BPA free", have been found to leach endocrine-disrupting chemicals (the substitute chemicals are no better than BPA, and may be worse). Examples: plastic food containers which then leach into foods, linings of metal beverage, formula, and food cans, soft plastic toys, dental sealants, consumer goods, receipts, personal care products that contain parabens or phthalates (e.g., found in lotions,sunscreens, fragrances), household products (such as cleaning products, vinyl shower curtains) , cars (that new car smell in car interiors), etc. Americans love plastics, but there is a serious human health cost.

NOTE: To minimize EDC exposure - try to avoid plastic food and beverage containers. Instead try to use glass, stainless steel, or ceramics. Eat as many unprocessed and fresh foods as possible. Use cloth shower curtains. Read labels and avoid BPA, phthalates, parabens. Avoid fragrances. Don't use or buy non-stick pans, stain and water-resistant coatings on clothing, furniture and carpets. When buying new furniture, check that it doesn't have added fire retardants.

Of course any public discussion of the harms from endocrine disrupting chemicals, as well as the newly released Endocrine Society report, is drawing sharp criticisms from the chemical industry (especially the American Chemistry Council, the largest trade group for the chemicals industry). Of course. We all know that the lobbying efforts by the chemical industry to suppress and deny the evidence of harm to humans from EDCs has been and will continue to be massive. Sadly, but at this point EDCs are found in almost everyone on earth. More about the report, from Science Daily:

Chemical exposure linked to rising diabetes, obesity risk

Emerging evidence ties endocrine-disrupting chemical (EDC) exposure to two of the biggest public health threats facing society -- diabetes and obesity. EDCs contribute to health problems by mimicking, blocking or otherwise interfering with the body's natural hormones. By hijacking the body's chemical messengers, EDCs can alter the way cells develop and grow. Known EDCs include bisphenol A (BPA) found in food can linings and cash register receipts, phthalates found in plastics and cosmetics, flame retardants and pesticides. The chemicals are so common that nearly every person on Earth has been exposed to one or more.  ...continue reading "New Report About Harms of Endocrine Disruptors"

Published on Leave a comment on Millions of Deaths Annually Due to Air Pollution?

A recent post (Air Pollution Can Kill You) discussed recent research that found that air pollution is linked to an overall increase in death rates, especially cardiovascular disease. But how many deaths each year are linked to air pollution? Recent research suggests that outdoor air pollution, mostly by fine particulate matter with a diameter smaller than 2.5 micrometers (PM2.5), leads to 3.3 million premature deaths per year worldwide, predominantly in Asia. The number one cause  worldwide is residential energy use such as heating and cooking, (India ,China, and the developing world).

But surprisingly agriculture or farming is number 2 worldwide. How can that be? Well, farms produce ammonia from fertilizer and animal waste. That ammonia then combines with sulfates from coal-fired power plants and nitrates from vehicle exhaust to form the soot particles that are the big air pollution killers. The United States had about 54,905 deaths in 2010 from soot and smog. Power plants and traffic (vehicle emissions) are big sources of the air pollution linked to deaths in the USA. From Medical Xpress:

Millions of premature deaths tied to air pollution

Outdoor air pollution leads to more than 3 million premature deaths per year, primarily in Asia, according to a letter published online Sept. 16 in Nature.

Johannes Lelieveld, Ph.D., from the Max Planck Institute for Chemistry in Germany, and colleagues used a global atmospheric chemistry model to investigate the link between premature mortality and seven emission source categories in urban and rural environments. The researchers found that outdoor air pollution, mostly by fine particulate matter with a diameter smaller than 2.5 micrometers (PM2.5), leads to 3.3 million premature deaths per year worldwide, predominantly in Asia. The largest impact on premature mortality globally comes from residential energy use such as heating and cooking, prevalent in India and China. In the United States, emissions from traffic and power generation are important. Agricultural emissions make the largest relative contribution to PM2.5 in the eastern United States, Europe, Russia, and East Asia, with the estimate of overall health impact depending on assumptions regarding particle toxicity. 

...continue reading "Millions of Deaths Annually Due to Air Pollution?"

Published on Leave a comment on We Each Give Off a Personal Microbial Cloud

Amazing! We each release a "personal microbial cloud" with its own "microbial cloud signature" every day. The unique combination of millions of bacteria (from our microbiome or community of microbes - including bacteria, viruses, fungi -  that live within and on us) can identify us. Not only do we each give off a unique combination, but we each give off different amounts of microbes - some more, some less. Some very common bacteria: Streptococcus, Propionobacterium, Corynebacterium, and Lactobacillus (among women).The microbes are given off with every movement, every exhalation, every scratching of the head, every burp and fart, etc. - and they go in the air around the person and settle around the person (they researchers even collected bacteria from dishes set on the ground around the person). From Science Daily:

The 'Pig-Pen' in each of us: People emit their own personal microbial cloud

We each give off millions of bacteria from our human microbiome to the air around us every day, and that cloud of bacteria can be traced back to an individual. New research focused on the personal microbial cloud -- the airborne microbes we emit into the air -- examined the microbial connection we have with the air around us. The findings demonstrate the extent to which humans possess a unique 'microbial cloud signature'.

To test the individualized nature of the personal microbial cloud, University of Oregon researchers sequenced microbes from the air surrounding 11 different people in a sanitized experimental chamber. The study found that most of the occupants sitting alone in the chamber could be identified within 4 hours just by the unique combinations of bacteria in the surrounding air. The findings appear in the September 22 issue of the open-access, peer-reviewed journal PeerJ.

The striking results were driven by several groups of bacteria that are ubiquitous on and in humans, such as Streptococcus, which is commonly found in the mouth, and Propionibacterium and Corynebacterium, both common skin residents. While these common human-associated microbes were detected in the air around all people in the study, the authors found that the different combinations of those bacteria were the key to distinguishing among individual people.

The analyses, utilizing analysis of suspended particulate matter and short-read 16S sequencing, focused on categorizing whole microbial communities rather than identifying pathogens. The findings emerged from two different studies and more than 14 million sequences representing thousands of different types of bacteria found in the 312 samples from air and dust from the experimental chamber.

"We expected that we would be able to detect the human microbiome in the air around a person, but we were surprised to find that we could identify most of the occupants just by sampling their microbial cloud," said lead author James F. Meadow, a postdoctoral researcher formerly from the Biology and the Built Environment Center at the University of Oregon."Our results confirm that an occupied space is microbially distinct from an unoccupied one, and and demonstrate for the first time that individuals release their own personalized microbial cloud," the authors concluded.

Image result for personal microbial cloud wikipediaSneeze. Credit: Wikipedia and CDC

Published on

 Perhaps a nutrient deficit is associated with depression? This study found that eating a Mediterranean diet or a similar diet in which fruits, vegetables, legumes (beans), nuts, and low in processed meats is associated with lower rates of depression. From Medical Xpress:

Fruit and vegetables aren't only good for a healthy body—they protect your mind too

Eating a Mediterranean diet or other healthy dietary pattern, comprising of fruit, vegetables, legumes, and nuts and low in processed meats, is associated with preventing the onset of depression, according to research published in the open access journal BMC Medicine. A large study of 15,093 people suggests depression could be linked with nutrient deficits..

The researchers compared three diets; the Mediterranean diet, the Pro-vegetarian Dietary Pattern and Alternative Healthy Eating Index-2010. Participants used a scoring system to measure their adherence to the selected diet, i.e. the higher the dietary score indicated that the participant was eating a healthier diet. Food items such as meat and sweets (sources of animal fats: saturated and trans fatty acids) were negatively scored, while nuts, fruits and vegetables (sources of omega-3 fatty acids, vitamins and minerals respectively) were positively scored.

The study included 15,093 participants free of depression at the beginning of the study. They are former students of the University of Navarra, Spain, registered professionals from some Spanish provinces and other university graduates....Questionnaires to assess dietary intake were completed at the start of the project and again after 10 years. A total of 1,550 participants reported a clinical diagnosis of depression or had used antidepressant drugs after a median follow-up of 8.5 years.

The Alternative Healthy Eating Index-2010 was associated with the greatest reduction of risk of depression but most of the effect could be explained by its similarity with the Mediterranean Diet. Thus, common nutrients and food items such as omega-3 fatty acids, vegetables, fruits, legumes, nuts and moderate alcohol intake present in both patterns (Alternative Healthy Eating Index-2010 and Mediterranean diet) could be responsible for the observed reduced risk in depression associated with a good adherence to the Alternative Healthy Eating Index-2010.

Almudena Sanchez-Villegas says, "A threshold effect may exist. The noticeable difference occurs when participants start to follow a healthier diet. Even a moderate adherence to these healthy dietary patterns was associated with an important reduction in the risk of developing depression. However, we saw no extra benefit when participants showed high or very high adherence to the diets....This dose-response pattern is compatible with the hypothesis that suboptimal intake of some nutrients (mainly located in low adherence levels) may represent a risk factor for future depression."

Two recent meta-analyses of studies looked at depression. The first found that in 12 out of 26 studies eating fish (but NOT fish-oil supplements) was linked to lower rates of depression. The researchers hypothesize that "Fish is rich in multiple beneficial nutrients, including n-3 polyunsaturated fatty acids, high-quality protein, vitamins, and minerals." Another meta-analysis looked at dietary patterns and depression and found that a high intake of fruit, vegetables, fish, and whole grains may be associated with a reduced depression risk. From Medscape:  Fish-Rich Diet May Significantly Reduce Depression Risk

Published on Leave a comment on Early Childhood Experiences Key to Preventing Allergies

It's official - the medical community has accepted that a key element in preventing allergies and asthma is early childhood exposure to allergens - whether peanuts, dust, or pets. Instead of avoiding the allergens (which was the medical advice for decades) - getting early exposure to them is key to preventing allergies. Apparently growing up on a farm is best (with exposure to farm dirt and dust), especially a dairy farm with animals and raw milk (a number of studies have found that unprocessed raw milk and its microbes also helps health). But if one doesn't live on a farm, then having furry pets in early childhood is also beneficial in reducing the incidence of allergies. The following study shows that microbes are involved - pet microbes were found in the guts of many of those children who did not develop early allergies! From Medscape:

Furry Pets 'Enrich' Gut Bacteria of Infants at Risk for Allergies

In a small, preliminary study, infants in households with furry pets were found to share some of the animals' gut bacteria - possibly explaining why early animal exposure may protect against some allergies, researchers say. The infants' mothers had a history of allergy, so the babies were at increased risk. It was once thought that pets might be a trigger for allergies in such children, the authors pointed out online September 3 in the Journal of Allergy and Clinical Immunology.

"Earlier it was thought that exposure to pets early in childhood was a risk factor for developing allergic disease," coauthor Dr. Merja Nermes, of the University of Turku in Finland, told Reuters Health by email. "Later epidemiologic studies have given contradictory results and even suggested that early exposure to pets may be protective against allergies, though the mechanisms of this protective effect have remained elusive."Adding pet microbes to the infant intestinal biome may strengthen the immune system, she said.  ...continue reading "Early Childhood Experiences Key to Preventing Allergies"

Published on Leave a comment on Air Pollution Can Kill You

Another study finding negative health effects from air pollution. This year I've posted several studies that found negative effects on the brain (and even cognition) from air pollution for people of all ages. Now this latest study found that in areas with air pollution, long-term exposure to outdoor fine particulate matter (PM2.5),which are fine particles in the air, are linked to an overall increase in risk of death, especially due to cardiovascular disease. The fine particles in the air contribute to the development of potentially fatal heart and lung diseases because they slip past the body's defenses and can be absorbed deep into the lungs and bloodstream. They are not sneezed or coughed out the way larger natural particles, like airborne soil and sand, are removed from the body's airways. From Science Daily:

Link between air pollution, increased deaths and increased deaths from heart disease affirmed

In what is believed to be the largest, most detailed study of its kind in the United States, scientists at NYU Langone Medical Center and elsewhere have confirmed that tiny chemical particles in the air we breathe are linked to an overall increase in risk of death. The researchers say this kind of air pollution involves particles so small they are invisible to the human eye (at less than one ten-thousandth of an inch in diameter, or no more than 2.5 micrometers across).

In a report on the findings, published in the journal Environmental Health Perspectives online Sept. 15, the scientists conclude that even minuscule increases in the amount of these particles (by 10 micrograms per cubic meter of air, for example) lead to an overall increased risk of death from all causes by 3 percent -- and roughly a 10 percent increase in risk of death due to heart disease. For nonsmokers, the risk increase rises to 27 percent in cases of death due to respiratory disease.

"Our data add to a growing body of evidence that particulate matter is really harmful to health, increasing overall mortality, mostly deaths from cardiovascular disease, as well as deaths from respiratory disease in nonsmokers," says lead study investigator and health epidemiologist George Thurston, ScD, a professor of population health and environmental medicine at NYU Langone. "Our study is particularly notable because all the data used in our analysis comes from government- and independently held sources."

According to Thurston, fine particles can contribute to the development of potentially fatal heart and lung diseases because they slip past the body's defenses and can be absorbed deep into the lungs and bloodstream. They are not sneezed or coughed out the way larger natural particles, like airborne soil and sand, are removed from the body's airways. Moreover, Thurston says, fine particles are usually made of harmful chemicals such as arsenic, selenium, and mercury, and can also transport gaseous pollutants, including sulfur and nitrogen oxides, with them into the lungs.

For their research, Thurston and his colleagues evaluated data from a detailed health and diet survey conducted by the National Institutes of Health (NIH) and the American Association of Retired Persons (AARP). The NIH-AARP study involved 566,000 male and female volunteers, ages 50 to 71, from California, Florida, Louisiana, New Jersey, North Carolina, Pennsylvania, and the metropolitan areas of Atlanta and Detroit. Analyzing information gathered about the participants between 2000 and 2009,....

Indeed, the team did not find any significant difference in the effect of particulate matter exposure between different sexes or age groups or by level of education. The researchers also noted that limiting the analysis to only the state of California, which has the most rigorous controls on air pollution, did not produce a different overall level of risk; instead, they found the same association between particulate matter exposure and increase in risk of death from all nonaccidental causes and from cardiovascular disease.