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Published on Leave a comment on Moderate Drinking Associated With Harm to the Brain

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.]

Published on Leave a comment on Ticks and Scary Powassan Virus

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

Published on Leave a comment on Popular Weedkiller Found In Pregnant Women – What Are the Effects On Babies?

 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

Published on Leave a comment on Walking Increases Blood Flow To the Brain

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.

Published on Leave a comment on Pollution Nanoparticles Found in Human Brains

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.

 

 

Published on Leave a comment on Common Pesticides and Behavioral Problems in Children

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 disorders. Researchers 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.

Published on Leave a comment on Benefit of Tea Drinking?

A study found that daily drinking of  tea (either black tea/oolong or green tea) is associated with a lower risk of "neurocognitive disorders" - in cognitive impairment in women, and in a lower risk of Alzheimer's disease in both men and women who are genetically predisposed to the disease (apolipoprotein E (APOE) genotype) - when compared to those who never or rarely drank tea. The researchers called long-term daily tea drinking as "neuroprotective".

The study followed 957 residents of Singapore for several years. All were "cognitively normal" when the study started (average age 64 1/2 years), but 72 people or 7.5% had developed neurocognitive disorders by the second follow-up (after 4 years). The study found that there was a dose-dependent relationship - the more tea that was drunk daily, the more protective it appeared to be. And it was most protective in those who consistently drank tea at both time points - when the study started and till the end. However, there was a gender difference - it seemed to protect women from neurocognitive disorders, but not men. But in those who were genetically predisposed to Alzheimer's - tea drinking was protective for both males and females. Further studies will follow up to see if the gender difference holds - they couldn't explain it.

The researchers also point out that tea drinking has a long history in Chinese culture as an natural "attention enhancer" and strong tea is drunk as to maintain alertness and concentration. Sounds a lot like why people drink coffee. From Medical Xpress:

Daily consumption of tea protects the elderly from cognitive decline

Tea drinking reduces the risk of cognitive impairment in older persons by 50 per cent and as much as 86 per cent for those who are genetically at risk of Alzheimer's. A cup of tea a day can keep dementia away, and this is especially so for those who are genetically predisposed to the debilitating disease, according to a recent study led by Assistant Professor Feng Lei from the Department of Psychological Medicine at National University of Singapore's (NUS) Yong Loo Lin School of Medicine. The longitudinal study involving 957 Chinese seniors aged 55 years or older has found that regular consumption of tea lowers the risk of cognitive decline in the elderly by 50 per cent, while APOE e4 gene carriers who are genetically at risk of developing Alzheimer's disease may experience a reduction in cognitive impairment risk by as much as 86 per cent.

He added, "Based on current knowledge, this long term benefit of tea consumption is due to the bioactive compounds in tea leaves, such as catechins, theaflavins, thearubigins and L-theanine. These compounds exhibit anti-inflammatory and antioxidant potential and other bioactive properties that may protect the brain from vascular damage and neurodegeneration. Our understanding of the detailed biological mechanisms is still very limited so we do need more research to find out definitive answers.

Published on Leave a comment on Blueberries and the Aging Brain

A new study was published that supports eating lots of blueberries (or drinking blueberry juice) for health - this time better brain functioning in people aged 65 to 77 who drank concentrated blueberry juice daily for 12 weeks. The people randomly assigned to the group drinking blueberry juice daily showed improvements in cognitive function, blood flow to the brain, and activation of the brain while carrying out cognitive tests. The people received MRIs (magnetic resonance imaging), as well as various blood tests and cognitive tests.

And how much did they drink of the juice daily? Thirty ml or 1 ounce of blueberry concentrate (which provided 387 mg anthocyanins) which was diluted with tap water. Anthocyanins are anti-oxidants that belong to a class of compounds called flavonoids, and are found in high concentrations in blueberries, cherries, and plums. The blueberry concentrate amount was equivalent to about 230 grams of blueberries - about 1 1/3 cups blueberries.

What was good about the study was that to eliminate bias people were both randomly assigned to the blueberry juice group or a placebo group (they drank a synthetic fruit cordial) - and it was "double-blind" so that no one knew who was in which group. Interestingly, people who were already eating more than 5 portions of fruits daily were excluded from the study - because so many other studies have already found all sorts of brain benefits from a diet with lots of fruits and berries. But the main conclusion from this and other related research is: eating lots of berries is good for you and has health benefits. From Medical Xpress:

Blueberry concentrate improves brain function in older people

Drinking concentrated blueberry juice improves brain function in older people, according to research by the University of Exeter. In the study, healthy people aged 65-77 who drank concentrated blueberry juice every day showed improvements in cognitive function, blood flow to the brain and activation of the brain while carrying out cognitive tests. There was also evidence suggesting improvement in working memory. Blueberries are rich in flavonoids, which possess antioxidant and anti-inflammatory properties.

Of the 26 healthy adults in the study, 12 were given concentrated blueberry juice - providing the equivalent of 230 g of blueberries - once a day, while 14 received a placebo. Before and after the 12-week period, participants took a range of cognitive tests while an MRI scanner monitored their brain function and resting brain blood flow was measured. Compared to the placebo group, those who took the blueberry supplement showed significant increases in brain activity in brain areas related to the tests. The study excluded anyone who said they consumed more than five portions of fruit and vegetables per day, and all participants were told to stick to their normal diet throughout. [Original study.]

Published on Leave a comment on Gut Bacteria Associated With Strokes

After writing about Lactobacillus sakei in the sinuses for several years (present in healthy sinuses, absent or less in those with chronic sinusitis, and also a treatment for chronic sinusitis), I wondered whether L. sakei is found anywhere else in the body. Today I read a study (conducted in Japan) about gut microbes and strokes and there it was - the presence of L. sakei in the gut.

Specifically, a study found that people who have ischemic strokes tend to have lower amounts ("depletion") of L. sakei in the gut than healthy people, even though it was detected in 80% of both groups.

The study found that in people with ischemic strokes there was evidence for the gut microbes being out of whack (dysbiosis), as well as more inflammation, and more of certain bacteria species (Atopobium cluster and Lactobacillus ruminis), and depletion of L. sakei bacteria.

The researchers took samples of stool (fecal samples) from each person of both groups (ischemic stroke group and healthy group) and analyzed the stool with modern tests (genetic sequencing) to see whether 22 groups of bacteria were in it. (Note that there are normally hundreds of species of bacteria living in a healthy person's gut, as well as viruses, fungi, etc.).

So once again it looks like L. sakei may be beneficial bacteria, even in the gut. The researchers were careful to point out that they couldn't say that certain bacteria caused the strokes - just that there was an association.

And what diet is associated with lower levels of inflammation in the body? Once again - a diet with lots of fruits, vegetables, whole grains, nuts, seeds, and legumes (think Mediterranean style diet). You want to feed the beneficial bacteria in the gut.

Excerpts from a research article by Yamashiro et al in PLoS One: Gut dysbiosis is associated with metabolism and systemic inflammation in patients with ischemic stroke

The role of metabolic diseases in ischemic stroke has become a primary concern in both research and clinical practice. Increasing evidence suggests that dysbiosis is associated with metabolic diseases. The aim of this study was to investigate whether the gut microbiota, as well as concentrations of organic acids, the major products of dietary fiber fermentation by the gut microbiota, are altered in patients with ischemic stroke, and to examine the association between these changes and host metabolism and inflammation.

We analyzed the composition of the fecal gut microbiota and the concentrations of fecal organic acids in 41 ischemic stroke patients and 40 control subjects via 16S and 23S rRNA-targeted quantitative reverse transcription (qRT)-PCR and high-performance liquid chromatography analyses..... Although only the bacterial counts of Lactobacillus ruminis were significantly higher in stroke patients compared to controls, multivariable analysis showed that ischemic stroke was independently associated with increased bacterial counts of Atopobium cluster and Lactobacillus ruminis, and decreased numbers of Lactobacillus sakei subgroup, independent of age, hypertension, and type 2 diabetes....Together, our findings suggest that gut dysbiosis in patients with ischemic stroke is associated with host metabolism and inflammation.   ...continue reading "Gut Bacteria Associated With Strokes"

Published on Leave a comment on Should Pregnant Women Be Warned To Avoid Licorice?

Avoid eating licorice during pregnancy? That licorice is a food to avoid during pregnancy (or only eat in tiny amounts) will be news to many. Most people think of licorice (or liquorice) as a candy, but it can also be used as a herbal medicine that can have negative health effects, especially in large doses (e.g, high blood pressure, loss of potassium). The licorice flavor comes from the root of the plant (licorice root). Licorice contains glycyrrhizin, which is in black licorice candy, and in some chewing gums, ice creams, syrups, soft drinks, supplements, herbal teas, and other products.

In 2016, the government of Finland warned against consuming licorice (including black licorice and salty licorice) during pregnancy. In the United States, the FDA does not warn pregnant women about eating licorice or licorice root. The National Institutes of Health (NIH) recommends that pregnant women avoid consuming large amounts of licorice root in food or taking it as a supplement. But how about small amounts of licorice? And what are possible effects during pregnancy?

A recent study in Finland compared children (average age of 12 1/2 years) whose mothers had either consumed little to no licorice during pregnancy or had consumed large amounts of licorice (high glycyrrhizin levels were calculated as more than 500 milligrams per week). Note that 500 mg glycyrrhizin is equal to 250 grams or 8.8 oz licorice. The researchers found that children whose mothers ate large amounts of licorice during pregnancy  were about 7 points lower on IQ tests, had poorer memory, and had higher rates of attention deficit/hyperactivity disorder problems than those whose mothers had eaten little or no licorice during pregnancy. High-consumption group girls had earlier and more advanced puberty, and were taller and heavier than those in the low-licorice group.

The researchers wrote that glycyrrhizin results in "glucocorticoid overexposure", which may affect the developing fetus, and the effects persist into early adolescence. The study researchers concluded that pregnant women should be informed that consumption of licorice and other food products containing glycyrrhizin may be associated with harm to their developing baby. A little licorice candy here and there during pregnancy seems to be OK (so don't panic!), but licorice or licorice root is not something that should be eaten or drunk (e.g.,in a tea) regularly. From Science Daily:

Pregnant women should avoid liquorice

A new Finnish study supports food recommendations for families with children in that women should avoid consuming large amounts of liquorice during pregnancy. The limit for safe consumption is not known. In the study, youths that were exposed to large amounts of liquorice in the womb performed less well than others in cognitive reasoning tests carried out by a psychologist. The difference was equivalent to approximately seven IQ points. Those exposed to liquorice also performed less well in tasks measuring memory capacity, and according to parental estimates, they had more ADHD-type problems than others. With girls, puberty had started earlier and advanced further.

The Glaku study carried out by the University of Helsinki, the National Institute for Health and Welfare and the Helsinki and Uusimaa hospital districts compared 378 youths of about 13 years whose mothers had consumed "large amounts" or "little/no" liquorice during pregnancy. In this study a large amount was defined as over 500 mg and little/no as less than 249 mg glycyrrhizin per week. These cutoffs are not based on health effects. 500 mg glycyrrhizin corresponds on average to 250 g liquorice.

Researchers suggest that pregnant women and women planning pregnancy should be informed of the harmful effects that products containing glycyrrhizin -- such as liquorice and salty liquorice -- may have on the fetus. In Finland, this is already reality. In January 2016, the National Institute for Health and Welfare published food recommendations for families with children, in which liquorice was placed in the 'not recommended' category for pregnant women. According to the recommendations, occasional consumption of small amounts such as a portion of liquorice ice cream or a few liquorice sweets is not dangerous.

As a result of animal experiments, the biological mechanism of the effects of liquorice is well known. Glycyrrhizin intensifies the effects of stress hormone cortisol by inhibiting the enzyme that inactivates cortisol. While cortisol is essential to the development of a fetus, it is detrimental in large amounts. It has long been known that glycyrrhizin causes higher blood pressure and shorter pregnancies in humans, but such long-lasting effects on the fetus have not been proven before. [Original study.]