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Lately more and more research has been finding health benefits with frequent consumption of extra virgin olive oil (EVOO). It is also a basic part of the popular Mediterranean diet - which emphasizes fresh fruits and vegetables, nuts, legumes (beans), whole grains, some fish, and extra virgin olive oil. Now a study conducted by investigators at Temple University in Philadelphia, Pennsylvania, suggests that the olive oil in the Mediterranean diet probably promotes healthy brain aging. The researchers said: "Our study is the first demonstration that EVOO can beneficially affect memory, amyloid plaques, and tau pathology, the hallmark lesions in the brain of Alzheimer's patients."

But... note that they are taking findings from their study done on mice and hypothesizing that this is what is also going on in humans.  Their study used specially bred mice (and only 22 in total) - one group which received extra virgin olive oil in their food (starting at 6 months of age), and the other not. The researchers found that after a few months of this diet that there were differences between the 2 groups when tested at 12 months (which is also when they were euthanized). Note that mice are short lived and after 6 months they are considered "mature adults".

The researchgers now plan to test varying daily doses of EVOO on humans soon - this way they can see what the minimal dosage is for beneficial effects (if any), and if there is a maximal dosage where there are negative health effects. In the meantime, enjoy olive oil in your diet - looks like it will benefit your health in a number of ways (herehere, and here). From Medscape:

Olive Oil Key Ingredient in Alzheimer's Prevention?

Extra-virgin olive oil (EVOO) appears to protect memory and learning ability and reduces the formation of beta amyloid (Aβ) plaques and neurofibrillary tangles in the brain — the classic hallmarks of Alzheimer's disease (AD) — new animal research shows. The study, conducted by investigators at Temple University in Philadelphia, Pennsylvania, suggests that it is the olive oil component of the Mediterranean diet that likely promotes healthy brain aging.... "And results are important enough to absolutely encourage people to consume greater amounts of EVOO. Given that it's been consumed for at least 2000 years, I do not anticipate any side effects," he added.  ...continue reading "Is Olive Oil Good For The Aging Brain?"

Could probiotics be used to treat depression? The medical site Medscape reported on a very small preliminary study (only 10 people) that tested that idea, with findings that suggested that taking certain probiotics does help treat the symptoms of mild to moderate depression. The bacteria taken were Lactobacillus helveticus and Bifidobacterium longum (in the product Probio'Stick). Specifically, the symptoms of mood, anhedonia (inability to feel pleasure), and sleep disturbance were significantly reduced after probiotoc therapy.

Sounds great, yes? But ....just a few months ago a much larger study was published where people were randomly assigned to either a placebo group or the treatment group (the same 2 probiotics: Lactobacillus helveticus and Bifidobacterium longum). It was also "double-blind" - so no one knew who got the placebo or the treatment. And here the results were: the probiotics did NOT help the depression symptoms. This study found "no evidence that the probiotic formulation is effective in treating low mood, or in moderating the levels of inflammatory and other biomarkers".

Why the different results? Maybe the "placebo effect" was why the 10 person study had a positive effect. Wanting and thinking something works can definitely influence results. (This is why ideally studies are double-blind, randomized, and with a placebo.) Or was it because the study was done "in association" with the manufacturers of Probio'Stick? Yup, it's not surprising the manufacturer of a product finds a "positive effect" from its product. Bottom line: Be careful and critical when reading "study results".

However, after saying all that - there is a "gut-brain axis" in humans, and some researchers are examining whether probiotics can treat various symptoms such as anxiety (here and here). So perhaps some other probiotic bacteria might work to treat depression.

The problematic study from Medscape: Probiotics Promising for Mild to Moderate Depression

Probiotics may be effective in reducing core depressive symptoms in treatment-naive patients with a mild to moderate form of the disorder, results of a new pilot study suggest. Investigators led by Caroline Wallace, PhD candidate, Queen's University, Kingston, Ontario, Canada, found that symptoms of mood, anhedonia, and sleep disturbance were significantly reduced with probiotic therapy after just 4 weeks, with results maintained at 8 weeks..... The hypothesis is that the effects are mediated via the gut-brain axis by reducing inflammation and increasing serotonin levels.

To assess the efficacy of probiotics in treatment-naive patients with depression, the researchers carried out a pilot study using Probio'Stick, a probiotic supplement that combines two different strains known to act on the gut-brain axis ― Lactobacillus helveticus R0052 and Bifidobacterium longum R0175. The 8-week, single-arm, open-label intervention pilot study involved 10 treatment-naive patients with major depressive disorder who were experiencing a current episode of depression..... Next steps will be to confirm these findings in a double-blind, randomized, placebo-controlled trial of Probio'Stick. 

Same probiotic bacteria, but no effect from the treatment. From The Australian and New Zealand Journal of Psychiatry: A double-blind, randomized, placebo-controlled trial of Lactobacillus helveticus and Bifidobacterium longum for the symptoms of depression.

No significant difference was found between the probiotic and placebo groups on any psychological outcome measure or any blood-based biomarker.

This study found no evidence that the probiotic formulation is effective in treating low mood, or in moderating the levels of inflammatory and other biomarkers. The lack of observed effect on mood symptoms may be due to the severity, chronicity or treatment resistance of the sample; recruiting an antidepressant-naive sample experiencing mild, acute symptoms of low mood, may well yield a different result. Future studies taking a preventative approach or using probiotics as an adjuvant treatment may also be more effective. Vitamin D levels should be monitored in future studies in the area. The results of this trial are preliminary; future studies in the area should not be discouraged.

Image result for dark chocolate Chocolate lovers can rejoice - because another study, which was actually a review of other studies - found that frequent consumption of chocolate, cocoa, and cocoa flavanols (an ingredient of cocoa) is linked with beneficial health effects. These included cardiovascular benefits, and dose-dependent improvements in cognition, attention, and memory. In other words - the more frequently one eats chocolate and cocoa (especially dark chocolate), the more beneficial health effects. So eat and enjoy! From Medical Xpress:

Cocoa and chocolate are not just treats—they are good for your cognition

A balanced diet is chocolate in both hands - a phrase commonly used to justify one's chocolate snacking behavior. A phrase now shown to actually harbor some truth, as the cocoa bean is a rich source of flavanols: a class of natural compounds that has neuroprotective effects. In their recent review published in Frontiers in Nutrition, Italian researchers examined the available literature for the effects of acute and chronic administration of cocoa flavanols on different cognitive domains. In other words: what happens to your brain up to a few hours after you eat cocoa flavanols, and what happens when you sustain such a cocoa flavanol enriched diet for a prolonged period of time?

Although randomized controlled trials investigating the acute effect of cocoa flavanols are sparse, most of them point towards a beneficial effect on cognitive performance. Participants showed, among others, enhancements in working memory performance and improved visual information processing after having had cocoa flavanols. And for women, eating cocoa after a night of total sleep deprivation actually counteracted the cognitive impairment (i.e. less accuracy in performing tasks) that such a night brings about. Promising results for people that suffer from chronic sleep deprivation or work shifts.

The effects of relatively long-term ingestion of cocoa flavanols (ranging from 5 days up to 3 months) has generally been investigated in elderly individuals. It turns out that for them cognitive performance was improved by a daily intake of cocoa flavanols. Factors such as attention, processing speed, working memory, and verbal fluency were greatly affected. These effects were, however, most pronounced in older adults with a starting memory decline or other mild cognitive impairments.

And this was exactly the most unexpected and promising result according to authors Valentina Socci and Michele Ferrara from the University of L'Aquila in Italy. "This result suggests the potential of cocoa flavanols to protect cognition in vulnerable populations over time by improving cognitive performance. If you look at the underlying mechanism, the cocoa flavanols have beneficial effects for cardiovascular health and can increase cerebral blood volume in the dentate gyrus of the hippocampus. This structure is particularly affected by aging and therefore the potential source of age-related memory decline in humans."

So should cocoa become a dietary supplement to improve our cognition? "Regular intake of cocoa and chocolate could indeed provide beneficial effects on cognitive functioning over time. There are, however, potential side effects of eating cocoa and chocolate. Those are generally linked to the caloric value of chocolate, some inherent chemical compounds of the cocoa plant such as caffeine and theobromine, and a variety of additives we add to chocolate such as sugar or milk." Nonetheless, the scientists are the first to put their results into practice: "Dark chocolate is a rich source of flavanols. So we always eat some dark chocolate. Every day." [Original study.]

Hah! Another study showing that YES, older adults have sex, and that more frequent sexual activity (as in at least weekly vs never or only monthly) may also be good for the brain and brain function in older adults. 73 people between the ages of 50 and 83 participated in this study. As the researchers wrote: "The current study demonstrates that older men and women who engage in regular sexual activity have better cognitive functioning than those who do not engage in sexual activity, or do so infrequently."

The researchers suggest that there could be biological reasons that sexual activity is beneficial - for example, it increases dopamine secretion. A number of researchers feel that the increased dopamine secretion from sexual activity is linked to improved working memory and executive function in older adults. But they admit that there could also be beneficial and "neuroprotective" effects from being involved in a social and physical relationship. At any rate, this was not a large study, and it can only show an "association", not definite cause. But other studies have similar findings - that overall cognitive scores are consistently higher in those who are sexually active compared to those than those who are not. From Science Daily:

Frequent sexual activity can boost brain power in older adults

More frequent sexual activity has been linked to improved brain function in older adults, according to a study by the universities of Coventry and Oxford. Researchers found that people who engaged in more regular sexual activity scored higher on tests that measured their verbal fluency and their ability to visually perceive objects and the spaces between them.

The study, published today in The Journals of Gerontology, Series B: Psychological and Social Sciences, involved 73 people aged between 50 and 83. Participants filled in a questionnaire on how often, on average, they had engaged in sexual activity over the past 12 months -- whether that was never, monthly or weekly -- as well as answering questions about their general health and lifestyle. The 28 men and 45 women also took part in a standardized test, which is typically used to measure different patterns of brain function in older adults, focusing on attention, memory, fluency, language and visuospatial ability.

It was these two sets of tests [verbal fluency and visuospatial ability] where participants who engaged in weekly sexual activity scored the most highly, with the verbal fluency tests showing the strongest effect. The results suggested that frequency of sexual activity was not linked to attention, memory or language. In these tests, the participants performed just as well regardless of whether they reported weekly, monthly or no sexual activity.

This study expanded on previous research from 2016, which found that older adults who were sexually active scored higher on cognitive tests than those who were not sexually active. But this time the research looked more specifically at the impact of the frequency of sexual activity (i.e. does it make a difference how often you engage in sexual activity) and also used a broader range of tests to investigate different areas of cognitive function. [Original study.]

Uh-oh... looks like any benefits of moderate alcohol consumption may not extend to the brain, at least in men. A  recent study found that moderate alcohol consumption over the course of a 30 years was associated with increased odds of hippocampal atrophy (brain damage in the hippocampus of the brain) - when compared to abstainers. Hippocampal atrophy causes memory problems and affects spatial navigation, and is also an early characteristic of Alzheimer's disease and other dementias. This result occurred in a dose dependent fashion - meaning the more that was drunk regularly, the more the atrophy in that area of the brain.

The heavier drinkers (when compared to abstainers) also had a faster decline in verbal skills ('verbal fluency") and changes in the white matter of the brain (specifically "corpus callosum microstructure"). There was no protective effect of light drinking when compared to abstainers (the 2 groups had similar results). **However, the researchers also reported: "The hippocampal atrophy associations we found in the total sample were replicated in men alone but not in women." Note: there were few women in the study (only 103 out of 527 studied) and even fewer were "heavy" drinkers (14 women), but one wonders - why not? Why didn't women drinkers have these brain changes?**

So how much did the moderate drinkers drink? They really didn't drink that much, but there were different groups: the abstainers (less than 1 unit of alcohol a week), “light” drinking was between 1 and <7 units, “moderate” drinking as 7 to <14 units a week for women and 7 to <21 units for men, and the heavier drinkers - those that drank more units per week, for an average of 30 units a week. What is a "unit" of alcohol? A medium glass of wine has about two units of alcohol, and so does a pint of  ordinary strength beer or lager. Thus the male moderate drinkers drank about a medium glass of wine or a beer each night, and maybe a little extra on the weekends. (In other words, not that much.) And the heaviest drinkers had a little more than two medium glasses of wine or two beers every night of the week, plus a little more on weekends.

What do the results mean?  The researchers said that  they don't have any evidence linking the brain changes they saw on the MRI brain scans to any negative general cognitive effects, but they did lose more "language fluency" with time. (They gave the people various tests.) The abstainer group (37 people) was very small - perhaps other lifestyle factors (e.g., nutrition) may be playing a part in the results. Also, if people  under-reported actual alcohol consumption - then it would throw off the results. While studies show that drinking can increase cancer risk, other studies have found that moderate drinkers seem to live longer than abstainers. From Medical Xpress:

Even moderate drinking linked to a decline in brain health, finds study

Alcohol consumption, even at moderate levels, is associated with increased risk of adverse brain outcomes and steeper decline in cognitive (mental) skills, finds a study published by The BMJ today. Heavy drinking is known to be associated with poor brain health, but few studies have examined the effects of moderate drinking on the brain—and results are inconsistent. So a team of researchers based at the University of Oxford and University College London set out to investigate whether moderate alcohol consumption has a beneficial or harmful association—or no association at all—with brain structure and function.

They used data on weekly alcohol intake and cognitive performance measured repeatedly over 30 years (1985-2015) for 550 healthy men and women who were taking part in the Whitehall II study. This study is evaluating the impact of social and economic factors on the long term health of around 10,000 British adults. Participants had an average age of 43 at the start of the study and none were alcohol dependent. Brain function tests were carried out at regular intervals and at the end of the study (2012-15), participants underwent an MRI brain scan.... After adjusting for these confounders, the researchers found that higher alcohol consumption over the 30 year study period was associated with increased risk of hippocampal atrophy - a form of brain damage that affects memory and spatial navigation.

While those consuming over 30 units a week were at the highest risk compared with abstainers, even those drinking moderately (14-21 units per week) were three times more likely to have hippocampal atrophy compared with abstainers. There was no protective effect of light drinking (up to 7 units per week) over abstinence.

Higher consumption was also associated with poorer white matter integrity (critical for efficient cognitive functioning) and faster decline in language fluency (how many words beginning with a specific letter can be generated in one minute). But no association was found with semantic fluency (how many words in a specific category can be named in one minute) or word recall. The authors point out that this is an observational study, so no firm conclusions can be drawn about cause and effect, and say some limitations could have introduced bias. [Original study.]

Many of us who who spend time outdoors worry about ticks. Just about everyone in the Northeast knows someone who has struggled with Lyme disease or one of the other diseases spread by ticks. An earlier post from June 8, 2015 noted that the CDC says that there are 14 known tick-borne diseases in the United States, and possibly 15 (if recently discovered Bourbon virus is included). Lyme disease is the most common, but people can be infected with more than one tick-borne illness at a time. [POST on Some Ways  To Get Rid of Ticks]

But recently I've seen news reports about a rare and scary tick borne disease called Powassan virus which is spread by deer ticks. News stories reported that an infant that developed the disease was the first case ever in Connecticut, and that the tick had been attached less than 3 hours on the child.

What is Powassan virus and should I be concerned? The good news is that it is very rare, but the bad news is that it's very scary: the virus can be transmitted in less than 2 hours (even as little as 15 minutes!) from an attached tick, and is fatal in about 10% of cases. It can cause encephalitis. And among those who recover, there is about a 50 percent chance of permanent neurological damage.  On the other hand, the CDC also says: "Many people who become infected with POW virus do not develop any symptoms." - But note that we don't know how many people get it and don't get serious symptoms, or any symptoms at all.

Powassan virus (POWV) is a tick-borne flavivirus that was first discovered in Ontario, Canada in 1956. At this time we don't know how prevalent it is in the US. From 2006 to 2015, an average of 7 cases of POWV were reported each year in the United States - only 77 cases in total. Although the virus is mostly found in the Northeast and Great Lakes region of the United States, some states outside of this area have been reporting their first cases.  One recent study found that the Powassan virus was in 1 to 2% of the ticks studied in Long Island in NY and Connecticut.

The Centers for Disease Control (CDC) states that: "Signs and symptoms of infection can include fever, headache, vomiting, weakness, confusion, seizures, and memory loss. Long-term neurologic problems may occur. There is no specific treatment, but people with severe Powassan virus illnesses often need to be hospitalized to receive respiratory support, intravenous fluids, or medications to reduce swelling in the brain. One study of 14  Powassan virus cases in NY state (2004-20012) reported that all of the hospitalized patients who received corticosteroids during their illness survived (looks like something helps).

From CNN: Experts warn of increases in tick-borne Powassan virus

Summer is nearly here, and it's bringing fears of a rare tick-borne disease called Powassan. This potentially life-threatening virus is carried and transmitted by three types of ticks, including the deer tick that transmits Lyme disease. Over the past decade, 75 cases have been reported in the northeastern states and the Great Lakes region, according to the US Centers for Disease Control and Prevention. Though no one can say how many infections will occur this year, warmer winters have led to an increased tick population, so experts predict rising tick-borne infections of many types.

Everyone is at risk for Powassan: Newborns, 20-somethings, the middle-aged, the elderly and the immunocompromised. Anyone bitten by an infected tick can get it, said Dr. Jennifer Lyons, chief of the Division of Neurological Infections and Inflammatory Diseases at Brigham and Women's Hospital in Boston. Infections are most likely during late spring, early summer and mid-fall, when ticks are most active.

"About 15% of patients who are infected and have symptoms are not going survive," said Lyons, who is also an assistant professor of neurology at Harvard Medical School. "Of the survivors, at least 50% will have long-term neurological damage that is not going to resolve." Although most infected people will never show symptoms, those who do become sick usually do so a few days to about a week after the tick bite, she said. The most common symptoms will be fever and headache. "You basically feel nonspecific flu-like stuff," Lyons said, including "muscle aches and pains; maybe you have a little rash on your skin, but almost certainly, you'll have a fever and the headache."The unlucky few who develop a more serious illness will do so "very quickly over the next couple of days," she said. "You start to develop difficulties with maintaining your consciousness and your cognition. ....

Just as there are no vaccines to prevent infection, there are also no treatments for Powassan. There are some experimental therapies we try when somebody comes in and they get here early enough and we get the therapy started early enough, but we have no idea if any of that works," Lyons said. Standard treatment includes intravenous fluids, though antiviral medications, systemic corticosteroids and other drugs have been tried in some patients.

Scientists also believe Powassan is on the rise based on studies that have identified an increasing number of infections in deer. Similarly, Lyme is showing increasing numbers. ....To make the matter more complicated, we are seeing greater number of ticks infected with other tick-associated pathogens, including babesiosis and anaplasmosis," Molaei said. Both babesiosis and anaplasmosis usually don't have symptoms, just like Powassan, though both may cause severe or even life-threatening illnesses.

Medical story about the Connecticut infant who developed Powassan virus. From Contagion Live: Connecticut Reports Its First Human Case of Powassan Virus

 News about the controversial pesticide Roundup and its active ingredient glyphosate just keep coming. Roundup is the most heavily used pesticide in the world, and it is used as a herbicide or weed-killer throughout the USA. Its use is rapidly rising, especially due to its use for preharvest applications on crops, and for genetically modified Roundup Ready crops. The chemical giant Monsanto (manufacturer of Roundup) insists that Roundup is safe for humans and the environment, but studies are indicating otherwise (see posts on Roundup). And yes, the pesticide and its residues are found wherever its presence is looked for. So one very important question is: If this heavily used pesticide is found in the foods we eat, and is around us (thus we have chronic low levels of exposure), what is it doing to us, if anything? 

This month the results of a study of 69 pregnant women receiving prenatal care at an Indiana obstetric practice was presented at a Children’s Environmental Health Network (CEHN) conference. The researchers reported that they found the presence of glyphosate and its breakdown products (aminomethylphosphonic acid or AMPA) in the urine of 91% of pregnant women. They found that higher levels of glyphosate were associated with lower than average birth weights and shorter pregnancy length (gestation age). Also, women living in rural areas had higher average glyphosate levels than women in urban/suburban regions. The researches suggested that it was because the rural women lived close to corn and soybean fields where glyphosate is heavily used.

The researchers also pointed out that this is especially worrisome because low birth weights and shortened pregnancy length (gestation) are seen as risk factors for many health and neurodevelopmental problems over the course of an individual’s life - lower cognitive abilities (including IQ), diabetes, heart disease, high blood pressure, and obesity. Of course the researchers plan to expand this research on more women.

But unfortunately US government agencies such as the FDA are not testing for the presence of glyphosate residues in foods (a major way we are exposed to glyphosate), even though they test for many other pesticides. So testing for the most heavily used pesticide in the world  in foods is deliberately not being done! It doesn't matter whether one thinks that Roundup (glyphosate) is harmful or not - we should know what foods this pesticide in the world appears in and at what levels. So far, whatever conventional foods are looked at, glyphosate residues are found. Even foods that one does not expect it in, such as honey. On the other hand, organic foods or crops are not allowed to use Roundup or glyphosate, so eating organic foods is the only way to avoid the pesticide. And of course, by not using Roundup or other glyphosate products on the property where you live.

The researchers and CEHN (Children’s Environmental Health Network) have put together a web-site documenting the increase in Roundup (glyphosate) use in the United States in the past few decades and why we should be concerned. There are many links at the thorough and well-researched site. If one looks at only a few pages, then look at the introduction page - The Project, the Birth Outcomes section, and the Biomonitoring Data page - which discusses "biomonitoring" to track levels of chemicals such as pesticides in human urine and blood, and why we should be concerned. They also discuss 2,4-D - another popular pesticide (herbicide or weed-killer), which is also used in many lawn "weed and feed" products. 2.4-D has serious health concerns, but its use is also rapidly increasing on farms due the increase in genetically modified crops (which allow it to be sprayed on crops without killing the crops).

Bottom line: We are being exposed to chronic low levels of pesticides in our environment and foods - and we really don't know what this is doing to us. We don't even know the extent of our exposures because it is not being measured. This is especially worrisome because our exposure to some of these pesticides is rapidly increasing.

From the investigative journalism site FERN: Researchers find glyphosate in pregnant women, worry about impact on infants

A team of scientists this week released early results of an ongoing study spotlighting concerns about the rising use of pesticides and reproductive risks to women and children. The researchers tested and tracked, over a period of two years, the presence of the common herbicide glyphosate in the urine of 69 expectant mothers in Indiana.

The team – led by Paul Winchester, medical director of the neonatal intensive care unit at the Franciscan St. Francis Health System and professor of clinical pediatrics at Riley Hospital for Children in Indianapolis, Ind. – found glyphosate residues in 91 percent of the women, and high levels of those residues appeared to correlate with shortened pregnancies and below-average birth weights adjusted for age. The findings alarmed the researchers because such babies are at increased risk of diabetes, heart disease, high blood pressure, and lower cognitive abilities. “Gestational age maximizes the size of your brain at birth, and any shortening is essentially a reduction of IQ points,” Winchester said in an interview with FERN’s Ag Insider. “It has not just health, but lifetime achievement implications.”

This is the first time that anyone has demonstrated glyphosate is present in pregnant women in the U.S., according to Winchester. However, the results were limited by a small sample size. He and his colleagues plan to submit their research to a peer-reviewed journal within the month and they hope to expand the study later this year. “The fact that we were able to find adverse effects on the small number of people we measured would imply a larger study is needed immediately to find out if this is prevalent everywhere,” Winchester says. “This is a critical piece of information that I think people should be concerned about.”

Glyphosate is the world’s most popular herbicide and the key ingredient in Monsanto’s Roundup weed killer. Globally, 9.4 million tons of glyphosate have been sprayed on crops, lawns, and gardens since the chemical was released on the market in 1974....Currently, concerns about the safety of glyphosate are at the center of a major national lawsuit. Monsanto is being sued by hundreds of U.S. consumers who say the company did not warn them, despite evidence, that the chemical can cause cancers such as non-Hodgkin lymphoma, a blood disease. A key piece of testimony in the suit is a 2015 International Agency for Research on Cancer (IARC) report stating that glyphosate is “probably carcinogenic to humans.” Monsanto contests the listing, citing rulings by the EPA, the European Chemicals Agency, and the European Food Safety Authority that did not find cancer risks.

Winchester has long studied the risks posed by agrochemicals, finding in a 2009 study that high levels of the farming chemical atrazine in water was associated with increased risk of genital birth defects in children. In the glyphosate study, Winchester and his colleagues considered whether water might again be the exposure route for the pregnant women they monitored. After testing water samples, the scientists concluded that it was not the source. They suspect diet may play a role. The Food and Drug Administration, however, recently suspended the testing of glyphosate residues in food, citing the need for improved validation methods.

Experts say the spread of weeds resistant to glyphosate in the Midwest is triggering intensification of herbicide use over longer periods of time. “Until this year, most herbicides in the Midwest were sprayed during a six-week window, but now heavy herbicide spray season will last at least four months, placing more women and children at heightened risk,” Phil Landrigan, dean for global health at Mount Sinai Medical School and a member of the research team, said in a statement. As a result, he and his colleagues predict the risk of reproductive problems and adverse birth outcomes will rise among women and children living in rural areas.

Another article on this research is from Carey Gillam for Huffington Post: Moms Exposed To Monsanto Weed Killer Means Bad Outcomes For Babies

An interesting study looked at what the act of walking does to our brain, and found that it can modify and increase the amount of blood that’s sent to the brain (which is viewed as beneficial for brain function). The study, performed by researchers at New Mexico Highlands University in the United States, found that the foot’s impact on the ground while walking sends pressure waves through the arteries, which can increase the blood supply to the brain. This is referred to as cerebral blood flow or CBF.

These results may help explain other studies that find those that walk frequently (about 6 to 9 miles per week) have "less cognitive impairment" or cognitive decline, fewer memory problems, and greater brain volume with aging.  Another good reason to get out and walk - good for the heart, the body, and the brain. From Science Daily:

How walking benefits the brain

You probably know that walking does your body good, but it's not just your heart and muscles that benefit. Researchers at New Mexico Highlands University (NMHU) found that the foot's impact during walking sends pressure waves through the arteries that significantly modify and can increase the supply of blood to the brain. The research will be presented today at the APS annual meeting at Experimental Biology 2017 in Chicago.

Until recently, the blood supply to the brain (cerebral blood flow or CBF) was thought to be involuntarily regulated by the body and relatively unaffected by changes in the blood pressure caused by exercise or exertion. The NMHU research team and others previously found that the foot's impact during running (4-5 G-forces) caused significant impact-related retrograde (backward-flowing) waves through the arteries that sync with the heart rate and stride rate to dynamically regulate blood circulation to the brain.

In the current study, the research team used non-invasive ultrasound to measure internal carotid artery blood velocity waves and arterial diameters to calculate hemispheric CBF to both sides of the brain of 12 healthy young adults during standing upright rest and steady walking (1 meter/second). The researchers found that though there is lighter foot impact associated with walking compared with running, walking still produces larger pressure waves in the body that significantly increase blood flow to the brain. While the effects of walking on CBF were less dramatic than those caused by running, they were greater than the effects seen during cycling, which involves no foot impact at all.

This post is more on the theme of nanoparticles and human health. My last post was about a study that examined how inhaled nanoparticles  (for example, from air pollution) travel from the lungs to the bloodstream.

Well, today's post is about a pretty shocking 2016 air pollution nanoparticle study which examined the brains (brain tissue) of 45 dead people  (ages 3 to 92) who had lived for a long time in two places with heavy  particulate air pollution - Mexico City and Manchester, England. Some of the British people also had Alzheimer's disease or dementia.

The researchers found evidence that minute nano-sized particles of magnetite from air pollution can find their way into the brain. There are 2 forms of magnetite (which is an iron ore) - one naturally occurring (jagged edges in appearance), and one found commonly in air pollution (smooth and rounded - from being created in the high temperatures of vehicle engines or braking systems). The researchers are concerned that the air pollution nanoparticles may increase the risk for brain diseases such as Alzheimer's.

One of the researchers (Prof Barbara Maher) has previously identified magnetite particles in samples of air gathered beside a busy road in Lancaster, England and outside a power station. She suspected that similar particles may be found in the brain samples, and that is what happened. "It's dreadfully shocking. When you study the tissue you see the particles distributed between the cells and when you do a magnetic extraction there are millions of particles, millions in a single gram of brain tissue - that's a million opportunities to do damage."..."It's a whole new area to investigate to understand if these magnetite particles are causing or accelerating neurodegenerative disease."

However, it must be stressed that at this time there is no proven link between these magnetite particles and any neurodegenerative diseases. They're just wondering.... they call finding these pollution nanoparticles "suggestive observations".

From Medical Xpress: Toxic air pollution nanoparticles discovered in the human brain

Tiny magnetic particles from air pollution have for the first time been discovered to be lodged in human brains – and researchers think they could be a possible cause of Alzheimer's disease. Researchers at Lancaster University found abundant magnetite nanoparticles in the brain tissue from 37 individuals aged three to 92-years-old who lived in Mexico City and Manchester. This strongly magnetic mineral is toxic and has been implicated in the production of reactive oxygen species (free radicals) in the human brain, which are associated with neurodegenerative diseases including Alzheimer's disease.

Professor Barbara Maher, from Lancaster Environment Centre, and colleagues (from Oxford, Glasgow, Manchester and Mexico City) used spectroscopic analysis to identify the particles as magnetite. Unlike angular magnetite particles that are believed to form naturally within the brain, most of the observed particles were spherical, with diameters up to 150 nm, some with fused surfaces, all characteristic of high-temperature formation – such as from vehicle (particularly diesel) engines or open fires. The spherical particles are often accompanied by nanoparticles containing other metals, such as platinum, nickel, and cobalt.

Professor Maher said: "The particles we found are strikingly similar to the magnetite nanospheres that are abundant in the airborne pollution found in urban settings, especially next to busy roads, and which are formed by combustion or frictional heating from vehicle engines or brakes."

Other sources of magnetite nanoparticles include open fires and poorly sealed stoves within homes. Particles smaller than 200 nm are small enough to enter the brain directly through the olfactory nerve after breathing air pollution through the nose.....The results have been published in the paper 'Magnetite pollution nanoparticles in the human brain' by the Proceedings of the National Academy of Sciences.

A good discussion of the study in The Scientist: Environmental Magnetite in the Human Brain

Image of magnetite nanoparticles from the exhaust plume of a diesel engine. Credit Maher et al study, 2016.

 

 

A microscopic image shows magnetite nanoparticles in the human brain. Barbara Maher et al study, 2016.

 

 

Another study has linked childhood behavioral problems to pesticide exposure, this time to pyrethroid insecticide exposure. Pyrethroids are synthetic pesticides (insecticides) that are increasingly used for personal use (mosquito repellents and treatments for head lice, scabies), on pets (for fleas), home use (e.g., Raid pesticides), and in agriculture.

Until recently, they have been viewed as "safer" and posing fewer risks to human health than older pesticides, but a growing body of research is finding that pyrethroid pesticides share similar neurocognitive health effects as older pesticides. Neurocognitive refers to the neural processes of the brain and central nervous system involved in cognitive functioning. Pyrethroids get into people various ways: through inhalation, absorbed through the skin, and ingested in food. And yes, they cross the placenta (they have been detected in the placental cord immediately after birth).

In this study, researchers looked at levels of pyrethroid metabolites (the breakdown products from pyrethroids) in the mother's urine during early pregnancy and in the child's urine when the child was 6 years of age. They looked at how social a child is (altruism), whether the child is inhibited and has difficulty sharing problems or asking for help (internalizing behaviors), as well as how defiant or disruptive a child is (externalizing behaviors, which can include hyperactivity and oppositionality).

Pyrethroids (the metabolites) were regularly detected in both mothers and children participating in the study. Internalizing disorders were associated with high levels of one pyrethroid metabolite (cis-DCCA, a breakdown product of permethrin, cypermethrin, and clyfluthrin) in pregnant mothers’ urine. Childhood exposure to pyrethroids (as measured in the child's urine) was linked to externalizing disordersResearchers hypothesized that the behavioral difficulties were due to changes in the child’s brain. The authors stated: “The current study suggests that exposure to certain pyrethroids at the low environmental doses encountered by the general public may be associated with behavioural disorders in children.” "Internalizing behaviors are inhibited and overcontrolled in nature, while children with

Other studies have also found negative health effects on children from pyrethroids -  for example, an association between synthetic pyrethroid exposure and ADHD hyperactivity and impulsivity. Recent research found that living near a farm field where pyrethroids are applied during a mother’s third trimester or just before conception corresponds with a greatly increased risk of having a child with autism spectrum disorder.

What can one do? Main one: try to avoid using and ingesting (in food) synthetic pyrethroids. This means avoid routine "pesticide treatments" of your home and garden, and instead use least-toxic methods to control pests around the home and garden (such as baits for insects, caulk holes, etc.). Try viewing weeds in the lawn as native wildflowers and the flowers as bee habitats (yes, you'll also be saving bees!). Eat as many organic foods (especially fruits and vegetables) as possible - this will lower the amount of pesticides in your body. This is because synthetic pyrethroids are not allowed in organic farming.  The good news is that pyrethroid pesticides leave the body within days, so with some lifestyle changes you can really lower your pesticide levels.

From Medscape:  'Safe' Insecticides Tied to Neurobehavioral Problems in Kids

Prenatal and childhood exposure to pyrethroid insecticides may adversely affect neurobehavioral development in children up to age 6 years, new research shows. A group of French researchers led by Jean-François Viel, MD, PhD, and Prof Andreas G. Franke, MD, both of the University of Mainz, Germany, investigated the associations between exposure to pyrethroid insecticides and behavioral skills in 6-year-olds.

Using a longitudinal design, the researchers assessed pyrethroid exposure in children prenatally and at age 6 years. They found that in 6-year-old children, increased prenatal concentrations of the cis-dimethylcyclopropane carbolic acid metabolite were associated with internalizing difficulties. A positive association was also found between the presence of childhood 3-phenoxybenzoic acid (3-PBA) and externalizing difficulties.

The researchers used a longitudinal design to assess the relationship between prenatal and childhood pyrethroid concentrations, using data from the French PELAGIE mother-child study. That study enrolled 3421 pregnant women from Brittany, France, between 2002 and 2006. Of this cohort, 287 randomly selected mothers agreed to participate in neuropsychological follow-up. Psychologists who were blinded to pyrethroid exposure levels in the study participants conducted neurodevelopmental assessments and maternal interviews to assess the home environment. They also collected children's urine samples as well as dust samples.