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An assortment of vitamin and health articles from the past year. (Note: Some other major Vitamin D study results were posted earlier this year, as well as today - search Vitamin D). Whether one should take vitamins is still being debated, with the most support being for supplementation with Vitamin D (specifically D3).The first summary is from pubmed.gov:

Taking vitamin D with the largest meal improves absorptioncally D3) and results in higher serum levels of 25-hydroxyvitamin D.

Many patients treated for vitamin D deficiency fail to achieve an adequate serum level of 25-hydroxyvitamin D [25(OH)D] despite high doses of ergo- or cholecalciferol. The objective of this study was to determine whether administration of vitamin D supplement with the largest meal of the day would improve absorption and increase serum levels of 25(OH)D.... it is concluded that taking vitamin D with the largest meal improves absorption and results in about a 50% increase in serum levels of 25(OH)D levels achieved. Similar increases were observed in a wide range of vitamin D doses taken for a variety of medical conditions.

 The following are all from Science Daily:

Long-term daily multivitamin supplement use decreases cataract risk in men, study finds

Long-term daily multivitamin supplement use may lower cataract risk in men, according to a study of nearly 15,000 male physicians. Half took a common daily multivitamin, as well as vitamin C, vitamin E and beta carotene supplements. The other half took a placebo. The researchers followed the participants to identify how many participants in each group developed new cases of two common eye diseases: cataract and age-related macular degeneration. Results showed a 9 percent decrease in risk for those that took the supplements.

Taking B vitamins won't prevent Alzheimer's disease, researchers conclude

Taking B vitamins doesn't slow mental decline as we age, nor is it likely to prevent Alzheimer's disease, conclude researchers who have assembled all the best clinical trial data involving 22,000 people to offer a final answer on this debate. When looking at measures of global cognitive function -- or scores for specific mental processes such as memory, speed or executive function -- there was no difference between those on B vitamins and those receiving placebo to a high degree of accuracy.

Children who drink non-cow's milk are twice as likely to have low vitamin D

Children who drink non-cow's milk such as rice, almond, soy or goat's milk, have lower levels of vitamin D in their blood than those who drink cow's milk, according to a new study. In North America, every 100 millilitres of cow's milk is required to be fortified with 40 units of vitamin D. Adding vitamin D to non-cow's milk, however, is voluntary.

Vitamin E intake critical during 'the first 1,000 days'

Amid conflicting reports about the need for vitamin E and how much is enough, a new analysis published today suggests that adequate levels of this essential micronutrient are especially critical for the very young, the elderly, and women who are or may become pregnant... "It's important all of your life, but the most compelling evidence about vitamin E is about a 1000-day window that begins at conception," Traber said. "Vitamin E is critical to neurologic and brain development that can only happen during that period. It's not something you can make up for later." Some of the best dietary sources of vitamin E -- nuts, seeds, spinach, wheat germ and sunflower oil -- don't generally make the highlight list of an average American diet. 

Vitamin D deficiency linked to higher risk of cardiovascular, cancer death

Analysis of pooled data showed a strong association between low vitamin D levels and risk of death in general death from cardiovascular diseases, death in from cancer, at least in older people with a history of cancer. "Going into our study, the effect of vitamin D supplementation on risk of death was not clear," said the lead investigator. "Our analysis confirms the protective nature of this substance especially in elderly patients."

High-dose vitamin D for ICU patients who are vitamin D deficient does not improve outcomes

Administration of high-dose vitamin D3 compared with placebo did not reduce hospital length of stay, intensive care unit length of stay, hospital mortality, or the risk of death at 6 months among patients with vitamin D deficiency who were critically ill, according to a study.

What do these substances do to our health? And our gut microbiome (microbial community)? Pay attention to the ingredient list on food labels. And consider buying more organic foods (which ban routine use of antibiotics and hormones,etc.). From Medical Daily:

Foods To Avoid? 10 Things In Americans' Favorite Foods That Are Banned In Other Countries

In a country so consumed with counting calories, the gluten-free fad, and fast food, the ingredients section on the back of packages are widely overlooked and riddled with internationally banned foods... Americans Still Eat These 10 Foods & Ingredients Banned Around The World:

 1. Farm-Raised Salmon Banned in Australia, New Zealand, and Russia...Farmed salmon don’t have a lot of room to swim, don’t follow their natural migration patterns, and have an unnatural diet of grains, which is why they’re fattier than wild salmon and contain 50 percent less omega-3 fats and protein. They’re grown with a mix of antibiotics, vitamins, drugs, and chemicals and don’t have wild salmon’s natural color, so they’re fed a synthetic astaxanthin to achieve the pinkish-red shade.

2. Ractopamine-Tainted Meat Banned in Russia, Mainland China, Taiwan, and 160 countries across Europe.... Ractopamine, also known as Paylean and Optaflexx, is a drug fed to livestock to reduce the fat content and enhance muscle, making the meat more profitable per animal. It was originally used to treat asthma and is found in 45 percent of pigs, 30 percent of ration-fed cattle, and an unknown percentage of turkeys. 

3. Genetically-Engineered Papaya   Banned in the European Union... 4. Flame Retardant in Drinks Banned in Japan and 18 European countries. In 1977, the FDA itself approved brominated vegetable oil (BVO), a patented flame retardant used in sodas and sports drinks in the U.S. Recently Coca-Cola and PepsiCo announced they’re working on removing the controversial BVO from their drinks as a result of petitions.

5. Processed Foods with Artificial Food Colors and Dyes  Banned Norway and Austria. If it’s not banned in a country outside of the U.S., it requires a warning label. Red 40, yellow 5, yellow 6, and blue 2 weave their way into the American ingredients list of a wide variety of foods. They’re the most commonly used dyes in the U.S., found in mac-and-cheese, cheddar flavored crackers, Jell-O, and children’s cereals. 

6. Arsenic-Laced Chicken  Banned in the European Union..  Since the 1940s, farmers have been feeding livestock arsenic to fight off disease; however, they now use it to make animals grow quicker and make the meat appear pinker and fresher....7. Bread with Potassium Bromate  Banned in the European Union, Canada, and China... 8. Olestra/Olean  Banned in the United Kingdom and Canada. Procter & Gamble created this cholesterol-free fat substitute for their fat-free snacks....  9. Preservatives BHA and BHT  Banned in Japan and the European Union. It’s found in anything from meat, to butter, beer, and breakfast cereals.

10. Milk and Dairy Products Laced with rBGH  Banned in Australia, New Zealand, Israel, Canada, and the European Union. In order to increase a cow’s milk production, scientists invented a rBGH, a synthetic version that mimics a natural hormone produced in their pituitary glands, known as bovine somatotropin. When rBGH came onto the market, the United Nations Safety Agency ruled unanimously not to endorse it in 1999, and eventually U.S. milk was internationally banned from being imported into their countries. In the U.S., approximately one in six dairy cows are injected with growth hormones on a regular basis, causing pus and antibiotic contamination and 16 other adverse health effects.  

To celebrate National Nut Day, two articles about health benefits of nuts. From Medical Daily:

National Nut Day 2014: Peanuts, Tree Nuts, And How Each Helps Your Health

For people who already eat plenty of meat and dairy products…nuts and ‘nutty’ legumes, like Brazil nuts, cashews, peanuts and walnuts, are a good nutritional alternative to meat,” Dr. Donal Murphy-Bokern, independent agri-environmental scientist and author of several studies on food system impacts, said in a statement. Heeding this advice means people can reap the benefits that come with eating nuts — Protein! Fiber! Omega-3 fatty acids! 

Nuts fall into two categories: peanuts (which are really legumes) and tree nuts. The latter includes Brazil nuts, cashews, hazelnuts, macadamias, pecans, pine nuts, pistachios, walnuts and America’s beloved almonds. ...” And existing research generalizes that eating nuts does everything from reduce risk for a slew of diseases, maintains weight, boosts gastrointestinal and bone health, even adds years to a person’s life.

As previously mentioned, nuts are pretty much equal in terms of calories. There are, however, some nuts that have more heart-healthy nutrients and fats than others. See: pistachios. This particular tree nut is high in healthy fats called monounsaturated fats (MUFA). MUFAs are often associated with belly fat.

One study published in the journal Nutrition found that when middle-aged adults at risk for heart disease and diabetes incorporated more pistachios into their diet, they weighed less and lessened their cholesterol and blood sugar levels after just six months. And a separate study from UCLA found people who regularly ate pistachios lost an average of 10 to 12 pounds. Almonds and cashews are additional nuts high in MUFAs. 

The Harvard School of Public Health reported, “several of the largest cohort studies, including the Adventist Study, the Iowa Women’s Health Study, the Nurses’ Health Study, and the Physicians’ Health Study have shown a consistent 30 percent to 50 percent lower risk of myocardial infarction, sudden cardiac death, or cardiovascular disease associated with eating nuts several times a week.”

Though almonds tend to be associated most with heart health, it’s actually walnuts that take the number one spot. ...Health reported a 2006 Spanish study, which “suggested that walnuts were as effective as olive oil at reducing inflammation and oxidation in the arteries after eating a fatty meal.”

Folate, as defined by Harvard Medical School, is “the naturally occurring form of the vitamin that is in foods or in the blood.” It’s also the vitamin that staves off brain atrophy, or the progressive loss of brain cells over time... A study published in the American Journal of Psychiatry found folate may ward off depression, too. And which nut is super rich in folate? Unsalted peanuts...peanuts are also high in vitamin E and niacin, both of which boost brain health. Hazelnuts and almonds are known to have concentrated amounts of E, too, so either nut is bound to help your noggin.

Study done in mice, but shows benefits of walnuts to brain. From Science Daily:

Fight against Alzheimer's disease: New research on walnuts

A new animal study published in the Journal of Alzheimer's Disease indicates that a diet including walnuts may have a beneficial effect in reducing the risk, delaying the onset, slowing the progression of, or preventing Alzheimer's disease. Research led by Abha Chauhan, PhD, head of the Developmental Neuroscience Laboratory at the New York State Institute for Basic Research in Developmental Disabilities (IBR), found significant improvement in learning skills, memory, reducing anxiety, and motor development in mice fed a walnut-enriched diet.

The researchers suggest that the high antioxidant content of walnuts (3.7 mmol/ounce) may have been a contributing factor in protecting the mouse brain from the degeneration typically seen in Alzheimer's disease. Oxidative stress and inflammation are prominent features in this disease, which affects more than five million Americans.

Walnuts have other nutritional benefits as they contain numerous vitamins and minerals and are the only nut that contains a significant source of alpha-linolenic acid (ALA) (2.5 grams per ounce), an omega-3 fatty acid with heart and brain-health benefits. The researchers also suggest that ALA may have played a role in improving the behavioral symptoms seen in the study.

Some recent research on sperm quality and implications for fertility. All from Science Daily:

Exposure to aluminum may impact on male fertility, research suggests

Research from scientists in the UK and France suggests that human exposure to aluminum may be a significant factor in falling sperm counts and reduced male fertility.Fluorescence microscopy using an aluminum-specific stain confirmed the presence of aluminum in semen and showed aluminum inside individual sperm.And the team of scientists, at the universities of Lyon and Saint-Etienne in France and Keele in the UK, found that the higher the aluminum, the lower sperm count.

Professor Exley said: "There has been a significant decline in male fertility, including sperm count, throughout the developed world over the past several decades and previous research has linked this to environmental factors such as endocrine disruptors"..."Human exposure to aluminum has increased significantly over the same time period and our observation of significant contamination of male semen by aluminum must implicate aluminum as a potential contributor to these changes in reproductive fertility."

Stress degrades sperm quality, study shows

Psychological stress is harmful to sperm and semen quality, affecting its concentration, appearance, and ability to fertilize an egg, according to a study. It is not fully understood how stress affects semen quality. It may trigger the release of steroid hormones called glucocorticoids, which in turn could blunt levels of testosterone and sperm production. Another possibility is oxidative stress, which has been shown to affect semen quality and fertility.

Twenty hours of TV a week linked to almost half sperm count of those who watch little TV

Healthy young men who watch TV for more than 20 hours a week have almost half the sperm count of men who watch very little TV, indicates a new study.

Cell phones negatively affect male fertility, new study suggests

Men who keep a cell phone in their pant pocket could be inadvertently damaging their chances of becoming a father, according to a new study. Previous research has suggested that radio-frequency electromagnetic radiation (RF-EMR) emitted by the devices can have a detrimental effect on male fertility. Most of the global adult population own mobile phones, and around 14% of couples in high and middle income countries have difficulty conceiving.

In control groups, 50-85% of sperm have normal movement. The researchers found this proportion fell by an average of 8 percentage points when there was exposure to mobile phones. Similar effects were seen for sperm viability. The effects on sperm concentration were less clear. 

Moderate weekly alcohol intake linked to poorer sperm quality in healthy young men

Moderate alcohol intake of at least 5 units every week is linked to poorer sperm quality in otherwise healthy young men, suggests research. And the higher the weekly tally of units, the worse the sperm quality seems to be, the findings indicate, prompting the researchers to suggest that young men should be advised to steer clear of habitual drinking.

Sperm size, shape in young men affected by cannabis use

Young men who use cannabis may be putting their fertility at risk by inadvertently affecting the size and shape of their sperm, according to new research. In the world's largest study to investigate how common lifestyle factors influence the size and shape of sperm, a research team found that sperm size and shape was worse in samples ejaculated in the summer months, but was better in men who had abstained from sexual activity for more than six days.

Another reason to eat vegetables, whole grains, seeds, fish, and nuts - they provide magnesium. From Medical Xpress:

Magnesium cuts diabetes risk

Getting enough magnesium in the diet may reduce the risk of diabetes, especially for those who already show signs of heading that way. A Tufts study led by Adela Hruby, N10, MPH10, N13, found that healthy people with the highest magnesium intake were 37 percent less likely to develop high blood sugar or excess circulating insulin, common precursors to diabetes.

Among people who already had those conditions, those who consumed the most magnesium were 32 percent less likely to develop diabetes than those consuming the least. The second association held true even when researchers accounted for other healthful factors, such as fiber, that often go along with magnesium-rich foods.The study, published in Diabetes Care, followed 2,582 participants in the Framingham Heart Study Offspring cohort for seven years. The study subjects had an average age of 54.

Only half of Americans get the recommended daily amount of magnesium in their diet, which is 400 to 420 milligrams for adult men and 310 to 320 milligrams for adult women. You can find it in whole grains, vegetables, fish, nuts and seeds and dark chocolate.

This research supports the growing evidence for the importance of microbes in the health of young children. Even the type of milk a child drinks is important. From Science Daily:

Pediatric allergology: Fresh milk keeps infections at bay

A study by researchers of Ludwig-Maximilians-Universitaet (LMU) in Munich shows that infants fed on fresh rather than UHT (ultra-pasteurized) cow's milk are less prone to infection. 

A pan-European study, led by Professor Erika von Mutius, Professor of Pediatric Allergology at LMU and Head of the Asthma and Allergy Department at Dr. von Hauner's Children's Hospital, reports that fresh cow's milk protects young children from respiratory infections, febrile illness and inflammation of the middle ear. As untreated cow's milk may itself contain pathogenic microorganisms and could pose a health risk, the researchers argue for the use of processing methods that preserve the protective agents present in raw milk.

The findings are the latest to emerge from the long-term PASTURE study, which is exploring the role of dietary and environmental factors in the development of allergic illness. The study initially recruited 1000 pregnant women who were asked to document their children's diet and state of health at weekly intervals during the first year of life.

"Among children who were fed on fresh, unprocessed cow's milk the incidence of head colds and other respiratory infections, febrile and middle-ear inflammation was found to be significantly lower than in the group whose milk ration consisted of the commercially processed ultra-pasteurized product," says Dr. Georg Loss. Ingestion of farm milk reduced the risk of developing these conditions by up to 30%, and the effect was diminished if the milk was heated at home before consumption. Conventionally pasteurized milk retained the ability to reduce the risk of febrile illness, while exposure to the higher temperatures used in UHT processing eliminated the effect altogether. 

"The effects of diverse milk treatments are presumably attributable to differentially heat-resistant components present in fresh milk. Compounds that are sensitive to heating seem to play a particularly important role in protection against respiratory-tract and ear infections," says Loss.

At the end of the first year of life, blood samples were obtained from the children enrolled in the study, and tested for biochemical indicators of immunological function. Infants fed on unprocessed milk were found to have lower levels of the C-reactive protein, which is a measure of inflammation status. "Other studies have shown that higher levels of inflammation are related to the subsequent emergence of chronic conditions such as asthma and obesity. Consumption of unprocessed milk may therefore reduce the risk of developing asthma," Loss explains.

Industrial processing of milk involves short-term heating of the raw product. Conventionally pasteurized milk has been exposed to temperatures of 72-75°C for 15 seconds, while ultra-pasteurized milk undergoes heating at around 135°C for a few seconds. The latter is also homogenized to disperse the milk fats, which prevents the formation of cream. 

In addition to fats and carbohydrates, cow's milk contains proteins that can modulate the function of the immune system. "In many respects, the composition of cow's milk is similar to that of human milk," says Loss. It has long been known that breast-feeding protects infants from infection, although how milk actually affects the early immune function remains unclear. It is possible that some of the factors involved interact directly with viruses or that they promote the development of a healthy immune system by altering the composition of the gut microflora.

That living in the country has positive effects on the immune system has been demonstrated in several previous studies. Together these investigations show, as Erika von Mutius notes, that "children who grow up on traditional dairy farms are least likely to develop allergies.

Views about exercise and aging have really changed over the last century. Bottom line: walk  - it's good for cognitive health, especially as you age. Try for at least 1 mile per day (1 mile = approx. 20 minutes brisk walk).

From The Atlantic: Walking for a Better Brain

 A “nerve specialist” from New York named J. Leonard Corning said in 1909 that he was opposed to “excessive exercise,” ... He thought that with the “over-cultivation of the physique the mentality suffered.” Corning wrote during a period when experts widely believed that brain cells didn’t regenerate. As a result, graceful aging was in large part a matter of learning to cope with gradually diminishing brain capacity. Modern science has shown that’s not the case; we do generate new brain cells throughout our lives, although the process can become increasingly imperfect and less efficient with age, as it does with much cellular activity.

One of the largest studies ever conducted was on a group of 121,000 nurses, who were surveyed on a wide range of their health and lifestyle habits starting in 1976. The survey was repeated every two years. This established a trove of valuable information, which public-health researchers have been fruitfully mining since. Among them is Rush University assistant professor Jennifer Weuve, who studied the data collected on 18,766 of the nurses, who were then ages 70 to 81, to unearth connections between exercise and cognitive ability. The results, published in The Journal of the American Medical Association, suggested that those who exercised the most—the group that maintained a median level of walking for six hours a week—were 20 percent less likely to show cognitive impairment than those who exercised the least.

Other long-term studies also show that even modest exercise can serve
 as a bulwark against dementia. A study started in 1989 with 299 elderly 
volunteers in the Pittsburgh area tracked mental acuity and exercise habits....The results, published in the journal Neurology, were sweeping and conclusive: Those who walked the most cut in half their risk of developing memory problems. The optimal exercise for cognitive health benefits, the 
researchers concluded, was to walk six to nine miles each week. That’s a mile to a mile and a half a day, without walking on Sundays if you’re inclined to follow Weston’s example of resting on the Sabbath. (This study concluded that walking an additional mile didn’t help all that much.)

A study written up in the Archives of Internal Medicine in 2001 tracked nearly six thousand women ages 65 and older for six to eight years. The women were given a cognitive test at the study’s beginning and end, the results of which were then correlated with how many blocks they walked daily. Those who walked the least had a drop of 24 percent in cognition. Those who walked the most still showed a decline, but of a lesser degree: 17 percent. The results were clear: “Women with higher levels of baseline physical activity were less likely to develop cognitive decline.”

Peter Snyder of Brown University’s Alpert Medical School, who studies the effects of aging on the brain, recently told National Public Radio that “what we’re finding is that of all of these noninvasive ways of intervening, it is exercise that seems to have the most efficacy at this point—more so than nutritional supplements, vitamins and cognitive interventions ... The literature on exercise is just tremendous,” he said.

Indeed, a 20-year-long study in 2010 found that walking just five miles per week “protects the brain structure” over a 10-year period in people with Alzheimer’s disease and in those who exhibit signs of mild cognitive impairment. “The findings showed across the board that greater amounts of physical activity were associated with greater brain volume,” the researchers concluded.

While different studies arrive at moderately different conclusions via various routes, the recent research of dozens of scientists more often than not converges at a single intersection. And that consistently suggests that if you exercise, your brain will be fitter than if you don’t. This applies to the young, those in the prime of their days, and especially to the elderly.

The 20-year 2010 study mentioned above, results from which were released by Cyrus Raji of the University of Pittsburgh, followed 426 older adults, including healthy people along with those showing mild cognitive impairment or the actual onset of Alzheimer’s. Across test subjects, more walking was shown to result in greater brain volume. “Unfortunately, walking is not a cure,” Raji said. “But walking can improve your brain’s resistance to [Alzheimer’s] disease and reduce memory loss over time.”

The possibilities are exciting. See my earlier posts on psychobiotics for more information. From Medical Xpress:

How gut bacteria ensures a healthy brain – and could play a role in treating depression

But medicine in the 21st century is rethinking its relationship with bacteria and concluding that, far from being uniformly bad for us, many of these organisms are actually essential for our health. Nowhere is this more apparent than in the human gut, where the microbiome  – the collection of bacteria living in the gastrointestinal tract - plays a complex and critical role in the health of its host.

The microbiome interacts with and influences organ systems throughout the body, including, as research is revealing, the brain. This discovery has led to a surge of interest in potential gut-based treatments for neuropsychiatric disorders and a new class of studies investigating how the gut and its microbiome affect both healthy and diseased brains.

The lives of the bacteria in our gut are intimately entwined with our immune, endocrine and nervous systems. The relationship goes both ways: the microbiome influences the function of these systems, which in turn alter the activity and composition of the bacterial community. We are starting to unravel this complexity and gain insight into how gut bacteria interface with the rest of the body and, in particular, how they affect the brain.

The microbiome-immune system link is established early on. Over the first year of life, bacteria populate the gut, which is largely sterile at birth, and the developing immune system learns which bacteria to consider normal residents of the body and which to attack as invaders. This early learning sets the stage for later immune responses to fluctuations in the microbiome's composition.

When a normally scarce strain becomes too abundant or a pathogenic species joins the community of gut bacteria, the resulting response by the immune system can have wide-reaching effects. Depression has been linked with elevated levels of such molecules in some individuals, suggesting that treatments that alter the composition of the microbiome could alleviate symptoms of this disorder.

Such an intervention could potentially be achieved using either prebiotics – substances that promote the growth of beneficial bacteria – or probiotics – live cultures of these bacteria. It is even possible that the microbiome could be manipulated by dietary changes.

In one experiment, researchers transplanted the human microbiome into germ-free mice (animals that have no gut bacteria) in order to study it in a controlled setting. They found that, simply by changing the carbohydrate and fat content of the mice's food, they could alter basic cellular functions and gene expression in the microbiome.

Depression is not the only psychiatric disorder in which the microbiome may play a role.Research in rodents, as well as a few preliminary studies in humans, indicate that the state of our resident microbes is tied to our anxiety levels.

This research also reveals the complexity of the relationship between the microbiome and psychological state. ...Researchers have shown that the presence or absence of microbes in young mice affects the sensitivity of the hypothalamic-pituitary-adrenal (HPA) axis – a key pathway in the body's stress response system. The activity of the microbiome during development thus sways how we respond to future stressors and how much anxiety they cause us.

How do the bacteria in our gut wield such influence over our brains and bodies? The mechanisms of microbiome-host interactions appear to be as numerous and varied as the interactions themselves.

Another interesting factoid about the human gut microbiome - it has circadian rhythms. This also has implications for timing of medical treatments and medicines. From Science Daily:

Jet lag can cause obesity by disrupting the daily rhythms of gut microbes

Organisms ranging from bacteria to humans have circadian clocks to help them synchronize their biological activities to the time of day. A study now reveals that gut microbes in mice and humans have circadian rhythms that are controlled by the biological clock of the host in which they reside. Disruption of the circadian clock in the host alters the rhythms and composition of the microbial community, leading to obesity and metabolic problems.

Disruption of the circadian clock in humans is a hallmark of relatively recent lifestyle changes involving chronic shift work or frequent flights across time zones. These widespread behavioral patterns have been linked to a wide range of diseases, including obesity, diabetes, cancer, and cardiovascular disease. But, until now, it has not been clear how changes in circadian rhythms increase the risk for these diseases.

In the new study, Elinav and his team set out to determine whether gut microbes could be the missing link. When they analyzed microbes found in fecal samples collected from mice and humans at different times of day, they discovered rhythmic fluctuations in the abundance of microbes and their biological activities. The host's circadian clock and normal feeding habits were required for the generation of these rhythmic fluctuations in the gut microbes.

When mice were exposed to changing light-dark schedules and abnormal 24 hr feeding habits, the microbial community lost its rhythmic fluctuations and changed in composition. Moreover, a high-fat diet caused these jet-lagged mice to gain weight and develop metabolic problems associated with diabetes. Similarly, jet lag in two humans who had traveled from the United States to Israel changed the composition of gut microbes, favoring the growth of bacteria that have been linked to obesity and metabolic disease.

Another reason to be concerned about air pollution. And another study showing a link with environmental chemicals (this time coarse and fine particulate matter, known as PM10, which arises in part from traffic-related air pollution) and autism. From Science Daily:

Researcher adds to evidence linking autism to air pollutants

A researcher at the University of Wisconsin-Milwaukee (UWM) has added to a growing body of evidence that links autism to air pollutants such as those generated by cars and trucks.

Amy Kalkbrenner's study, published this week online at the journal Epidemiology, showed that pollution's impact on autism rates in North Carolina is similar to results of pollution-autism studies in California -- despite weather and climate differences between the two states. In addition, the work of Kalkbrenner and her colleagues, building on previous studies, showed that women in the third trimester of pregnancy were more susceptible to the damaging effects of air pollution on their unborn child.

"It adds another piece supporting the hypothesis that environmental chemicals are part of the autism puzzle," says Kalkbrenner, an assistant professor in UWM's Joseph J. Zilber School of Public Health. Autism, a spectrum of disorders affecting interpersonal relations and work achievement, now affects some 1 in 68 children in the U.S.

Her research team focused on exposure to coarse and fine particulate matter, known as PM10, which arises in part from traffic-related air pollution...Researchers used a new, more exact tool to measure the levels of particulate matter in smaller slices of time, based on pollution at the family's address during pregnancy. With this method, they were able to compare exposures during specific weeks of pregnancy. The approximately one thousand children who later developed some form of autism spectrum disorders were then compared to all other children.

Reasons for increased susceptibility in the third trimester of pregnancy are not known at this time. However, Kalkbrenner says this finding is consistent with theories that show links between autism and altered brain network development, specifically synaptic connections that are developing during the final months of pregnancy.