Skip to content

Surprised...is how I felt after reading this study. According to the study, activity levels and exercise in mid-life are not linked to cognitive fitness and dementia later on in life. Instead, higher levels of physical activity and exercise has a beneficial effect on the brain in the short term (e.g., within 2 years or so). This finding of no long-term benefits, but only short-term benefits to the brain from exercise, is contrary to some other (cross-sectional) studies, but is supported by another recent study ("no evidence of a neuroprotective effect of physical activity").

The beauty of this study is that it followed 646 people for 30 years (from a median age of 46 years in 1978 and 77 years in 2008). The negative is that according to this study, physical exercise in mid-life does not seem to delay or prevent the onset of dementia and Alzheimer's later on in life. Eh... From Medical Xpress:

Physical activity in midlife not linked to cognitive fitness in later years, long-term study shows

A study led by Johns Hopkins Bloomberg School of Public Health researchers that tracked activity levels of 646 adults over 30 years found that, contrary to previous research, exercise in mid-life was not linked to cognitive fitness in later yearsThe finding suggests that physical activity may not help maintain cognitive function, or help avoid or delay the onset of the debilitating conditions like dementia and Alzheimer's

The study, which appears online in the Journal of Alzheimer's Disease, did find that activity levels among study participants in the later years were associated with high cognitive function two years later. This supports earlier research findings that exercise may help to maintain cognitive fitness in the short term.

There is no known treatment or cure for Alzheimer's or dementia, syndromes that involves declining memory, confusion and eventually limited ability to perform daily tasks. To date, there are no preventive measures, such as physical exercise, brain games or a diet regimen, that have been proven to help delay or altogether prevent its onset. The researchers undertook the study because of a growing consensus that physical activity levels helps prevent Alzheimer's, however much of the evidence for this thinking is based on cross-sectional studies that compare responses from one group of participants with another at a given point in time or within a very short duration, typically several years..... That's where longitudinal studies, which look at the same group of participants over a long time, are more helpful.

The researchers used data from the Johns Hopkins Precursors study.... The researchers used responses from 1978 through 2008 from 646 participants (598 men, 48 women) to calculate so-called metabolic equivalents, which quantify physical activity levels. Participants were also asked whether they regularly exercise to a sweat. The team administered cognitive tests in 2008, and, using participants' medical records, scored for dementia through 2011. The researchers identified 28, or 4.5 percent of the cohort, to have Alzheimer's.

No physical activity measure in mid-life was associated with late-life cognitive fitness or onset of dementia. The study confirmed findings of other cross-sectional studies, that higher levels of physical activity and exercise measured close in time to the cognitive testing were associated with better cognitive functioning. The authors also looked at whether patterns of change in physical activity levels over the life span were associated with cognitive health and found no relationships.

The idea that exercise might play a role in preventing or limiting Alzheimer's makes sense, the researchers say, because physical activity, at least in mouse models, has shown less accumulation of B-amyloid plaques, which are thought to play a role in dementia, including Alzheimer's. In addition, physical activity improves blood flow to the brain, which is linked to better cognitive performance. This may explain why studies find that exercise may contribute to cognitive fitness in the short term.

  Should tackle football continue to be played in its current form? A study with horrifying results that was published this week in the Journal of the American Medical Association raises that question once again. The study examined 202 brains of people who had formerly played football for varying lengths of time and at varying levels (some who only played pre-high school, some at high school, college level, semi-professional, or Canadian football league). They found the highest percentage of  the degenerative brain disease chronic traumatic encephalopathy (CTE) among former NFL players (110 out of 111 brains). However, the overall incidence of CTE was 87% when looking at all 202 brains. They also found that the 3 out of 14 former high school players had mild CTE, but the majority of former college, semiprofessional, and professional players had severe CTE.

The one thing to keep in mind is that the study only examined donated brains of former football players  - which means that the family members were concerned about CTE in the former player (perhaps there were symptoms suggestive of CTE). So we don't know the actual percentage of CTE in currently playing and former football players. But studies (here. here, and here) do show damage from hits received during football games and practice at even the grammar and high school level - and the damage can be from subconcussive hits.

But note that concussions and subconcussive hits (head trauma) also occur in other sports, such as soccer. Everyone agrees we need more studies, and we also need to rethink how some games are played in childhood to protect developing brains. From NPR:

Study: CTE Found In Nearly All Donated NFL Player Brains

As the country starts to get back into its most popular professional team sport, there is a reminder of how dangerous football can be. An updated study published Tuesday by the Journal of the American Medical Association on football players and the degenerative brain disease chronic traumatic encephalopathy reveals a striking result among NFL players. The study examined the brains of deceased former football players (CTE can only be diagnosed after death) and found that 110 out of 111 brains of those who played in the NFL had CTE. CTE has been linked to repeated blows to the head — the 2015 movie Concussion chronicled the discovery of CTE's connection to football.

In the study, researchers examined the brains of 202 deceased former football players at all levels. Nearly 88 percent of all the brains, 177, had CTE. Three of 14 who had played only in high school had CTE, 48 of 53 college players, 9 of 14 semiprofessional players, and 7 of 8 Canadian Football League players. CTE was not found in the brains of two who played football before high school.

CTE study several years ago by McKee and her colleagues included football players and athletes from other collision sports such as hockey, soccer and rugby. It also examined the brains of military veterans who had suffered head injuries. The study released Tuesday is the continuation of a study that began eight years ago. In 2015, McKee and fellow researchers at the Department of Veterans Affairs and Boston University published study results revealing 87 of 91 former NFL players had CTE.

McKee is chief of neuropathology at VA Boston Healthcare System and director of the CTE Center at the BU School of Medicine. Speaking about the new numbers, she says it's "startling to be able to gather 177 examples of CTE" in a relatively short period of time (the past eight years). "While we still don't know what the incidence is in the general population or in the general population of football players," she says, "the fact that we were able to gather this many cases [in that time frame] says this disease is much more common than we previously realized." "We need a very well-constructed longitudinal study," says McKee, "looking at young individuals playing these sports. We need to follow them for decades...." [Original study.]

  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.

For the study, the investigators tested the potentially beneficial effects of EVOO on triple transgenic mice. These mice are specifically bred to develop key pathologic features of AD (Alzheimer's disese), including amyloid plaques and neurofibrillary tangles. The animals were divided into two groups. One group received EVOO-enriched chow, and the other received regular chow without EVOO. The olive oil was introduced into the diet when the mice were 6 months of age, before they began to develop symptoms of AD..... The mice were subjected to the same behavioral tests at both 9 and 12 months of age, after which they were euthanized and their brains were examined for the presence of key pathologic features of AD.

The researchers confirmed that mice fed the EVOO-enriched diet performed significantly better at both 9 and 12 months on tests designed to assess working memory, spatial memory, and learning abilities compared with mice fed regular chow. The researchers also found a statistically significant reduction in the amount of Aβ peptides deposited in the brains of the EVOO-treated animals compared with controls. There was also a significant reduction in the phosphorylated forms of tau in mice fed the EVOO-enriched chow compared to controls, although olive oil had no effect on total tau levels in the same region of the brain.

The investigators also examined whether the improvements in cognitive performance and brain pathology that were observed in EVOO-treated mice might be the result of an improvement in synaptic integrity. Once again, they found greater preservation in the integrity of the synapses between neurons in EVOO-fed mice compared with controls....  Furthermore, there was a dramatic increase in nerve cell autophagy activation in brain cells from the EVOO-fed animals compared with controls. Dr Pratico explained that autophagy is a mechanism by which cells digest proteins that are produced in excess or that are abnormal. In this particular animal model, autophagy digests and gets rid of both amyloid plaques and phosphorylated tau.

"Thanks to the autophagy activation, memory and synaptic integrity were preserved, and the pathological effects in animals otherwise destined to develop Alzheimer's disease were significantly reduced. This is a very important discovery, since we suspect that a reduction in autophagy marks the beginning of Alzheimer's disease."

 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.]

Image result for older couple holding hands 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.

05 bug bites tick burrowed Engorged tick attached to human skin  Credit: CNN

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.