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Category: brain

Published on Leave a comment on Another Widely Used Pesticide Is Linked to Parkinson’s Disease

Yikes! While writing the last post, I came across a recent study of another pesticide linked with the development of Parkinson's disease. While the weed killer paraquat has long been linked to Parkinson's disease, certain other pesticides are also linked - such as chlorpyrifos.

Chlorpyrifos is a widely used insecticide in agriculture. While now banned for household use, homeowners used to use it (e.g., in the product Raid) for insect control for many years.

The study researchers (at the medical school at UCLA) found that long-term residential exposure to chlorpyrifos is associated with more than a 2.5 times increased risk of developing Parkinson's disease. They studied humans, mice, and zebrafish to reach their conclusions. They found that chlorpyrifos damages dopamine-producing brain cells - which are the same cells damaged in Parkinson's disease.

From Medical Xpress: Widely used pesticide linked to more than doubled Parkinson's risk

A new study from UCLA Health has found that long-term residential exposure to the pesticide chlorpyrifos is associated with more than a 2.5-fold increased risk of developing Parkinson's disease. ...continue reading "Another Widely Used Pesticide Is Linked to Parkinson’s Disease"

Published on Leave a comment on The Link Between Parkinson’s Disease and the Pesticide Paraquat

Once again, a pesticide banned in many other countries due to its harmful effects on humans and the environment, is allowed to be used in the US. The incredibly dangerous pesticide paraquat is banned in more than 70 countries, including China (where it is made), but not the US. Paraquat (paraquat dichloride) is a highly toxic weed killer used by farmers.

Many studies and farmers themselves report that paraquat causes Parkinson's disease. Currently there are thousands of lawsuits against Syngenta, the manufacturer, and Chevron USA (the seller). [NOTE: Of course Syngenta denies any link between paraquat exposure and Parkinson's disease.] The US Geological Survey reports that between 11 million and 17 million pounds of paraquat are sprayed annually on American farms. But here's the crazy part: use of the pesticide in the US is increasing annually. WTH?

By the way, Parkinson’s disease is the fastest growing neurological disorder in the world, with about 90,000 new cases diagnosed each year in the US. A number of pesticides are linked with the increase, with the link between paraquat and Parkinson's disease known since the 1980s (by research done by independent researchers). Evidence is growing that it's not just direct exposure (contact with it), but also chronic low level exposure that is linked to Parkinson's disease (e.g., living near a farm - thus inhalation of low levels in the air).

What will it take to ban the use of paraquat in the US? (Yes, there are alternatives to paraquat.) Doesn't look likely in the near future. In fact, the chemical/pesticide industry is trying to pass state and federal laws that would protect pesticide manufacturers from liability.

Excerpts from an investigative piece. From nj.com news: Thousands of U.S. farmers have Parkinson’s. They blame a deadly pesticide.

Paul Friday remembers when his hand started flopping in the cold weather – the first sign nerve cells in his brain were dying.

He was eventually diagnosed with Parkinson’s, a brain disease that gets worse over time. His limbs got stiffer. He struggled to walk. He couldn’t keep living on his family farm. Shortly afterward, Friday came to believe that decades of spraying a pesticide called paraquat at his peach orchard in southwestern Michigan may be the culprit.

...continue reading "The Link Between Parkinson’s Disease and the Pesticide Paraquat"

Published on Leave a comment on High Fat Cheese and Lower Risk of Dementia

Great news for cheese lovers! A recent study found regularly eating full-fat (high-fat) cheese and cream was associated with a lower risk of developing dementia. Some examples of full-fat cheese include cheddar, Swiss, Parmesan, Brie, Gouda, Provolone, Colby, Havarti, Mozzarella (full-fat), and cream cheese.

This was a long-running study (27,670 persons for 25 years) conducted in Sweden. High-fat cream and cheese consumption was inversely associated with dementia, Alzheimer's disease, and vascular dementia. Eating more than 50 grams (about 1/3 cup or 2 slices) of full-fat cheese per day was associated with a 13% to 17% lower risk of Alzheimer's, and more than 20 grams (about 1 1/2 tablespoons) of full-fat cream was linked to a 16% lower risk of dementia overall.

However, consumption of low-fat cheese, low-fat cream, milk (low or high fat), and butter showed no association with dementia.

From Science Daily: Study links full-fat cheese to lower dementia risk

...continue reading "High Fat Cheese and Lower Risk of Dementia"

Published on Leave a comment on Pesticides and Pediatric Cancers

Cancer is feared by all. It seems to strike randomly, but not always. Certain cancers that occur in both children and adults, such as brain cancer and leukemia, are linked with some commonly used pesticides. Exposures to these pesticides occur many ways - whether from nearby  farm use, or in foods or the water  we drink, or air (pesticide drift), or residential use (e.g., the weed killer 2,4-D on lawns). Exposure is typically not to just 1 harmful chemical, but to mixtures of pesticides, especially on farms.

Children are especially vulnerable to pesticides. Research shows that there is an increase in some cancers in children in farm areas (e.g., Nebraska and the US midwest) where pesticides are heavily used. A recent study by Dr. Taiba and colleagues found that in Nebraskan counties with heavy farm pesticide use (especially Holt county) children living there had an increase not just in "overall pediatric cancers", but in specific types of cancers. These cancers included brain and other central nervous system tumors, leukemia, and lymphoma.

Keep in mind that in the US millions of pounds of pesticides are used each year, with farm areas having the heaviest use. Dr. Taiba reported that the US is the #1 country in the world in pesticide use. Among the most heavily used in the Nebraskan farms are atrazine, 2,4-D, glyphosate, dicamba, paraquat.

But don't ignore residential use of pesticides. Many of the same pesticides, such as glyphosate and 2,4-D, are commonly used in residential areas, especially for weed and insect control. Feed and Weed, which is used on lawns for weed control, contains 2,4-D. Pesticides have harmful effects on humans, and yet pesticide use is increasing annually.

From Beyond Pesticides: Dire Pediatric Cancer Risk Linked to Pesticide Mixtures, Laws To Protect Children Found To Be Lax

Childhood cancers are on the rise globally; in the U.S. cancer is the second most common cause of death in children between one and 14 years old, and the fourth most common in adolescents. A recent study of Nebraska pesticide use and pediatric cancer incidence by researchers from the University of Nebraska Medical Center and the University of Idaho Department of Fish and Wildlife Sciences found positive associations between pesticides and overall cancer, brain and central nervous system cancers, and leukemia among children (defined as under age 20). ...continue reading "Pesticides and Pediatric Cancers"

Published on Leave a comment on Loss of Smell from A COVID Infection Can Linger For At Least Two Years

Millions of us have had a least one COVID infection. Many suffered a loss of smell during the infection. A recent study by NYU Langone researchers found that the loss of smell can linger for at least 2 years after the infection. And even if you thought that your smell was never impacted or that it has recovered, it actually may not have fully recovered, but only partially recovered.

Among the 3525 participants in the study that reported a loss of smell during a COVID infection - 80% still  had not fully recovered their sense of smell 2 years later, and for 23% it was severely diminished or lost. Interestingly, 66% of persons who originally had a COVID infection, but did not notice any smelling issues, also scored abnormally low on the evaluation done 2 years after the infection.

It can be said that their sense of smell has dulled (olfactory dysfunction). This reduced ability to smell is called hyposmia. Researchers administer a 40-odor test to persons to determine their smelling ability. To help recover the sense of smell, vitamin A supplementation and olfactory training are being tried.

From Science Daily: Millions could be living with hidden smell loss after COVID without knowing

People who suspect that their sense of smell has been dulled after a bout of COVID-19 are likely correct, a new study using an objective, 40-odor test shows. Even those who do not notice any olfactory issues may be impaired. ...continue reading "Loss of Smell from A COVID Infection Can Linger For At Least Two Years"

Published on Leave a comment on Commonly Used Chemical and Parkinson’s Disease

Over and over studies have found links with certain toxic chemicals (some pesticides and the chemical trichloroethylene) and Parkinson's disease. Another recent study found that long-term exposure to high levels of the chemical trichloroethylene (TCE) in the outside air increases the risk of developing Parkinson's disease.

TCE is an industrial solvent used in numerous industrial (as a degreaser), consumer, military, and medical applications. For example, it is used in dry cleaning clothes, removing paint, as a degreaser, carpet cleaner, and engine cleaner. Unfortunately, since it is environmentally persistent, it lingers in the air, water (e.g., in the military base Camp Lejeune), and soil across the US.

Bottom line: Outdoor air pollution also matters, not just the chemicals you are directly exposed to (e.g., in your job). TCE is a hazardous air pollutant, so avoid living (if you can) near a TCE emitting facility (especially in Lebanon, Oregon and Corydon, IN) because the risk of developing Parkinson's disease is the highest for people living near there.

From Science Daily: The invisible chemical in the air that could be raising Parkinson’s risk

Long-term exposure to the industrial solvent trichloroethylene (TCE) outdoors may be linked to an increased risk of Parkinson's disease, according to a large nationwide study published in the October 1, 2025, issue of Neurology, the medical journal of the American Academy of Neurology. ...continue reading "Commonly Used Chemical and Parkinson’s Disease"

Published on Leave a comment on Lifestyle Changes That Benefit the Aging Brain

As people age, they frequently start wondering what they can do to prevent memory and thinking problems, and especially dementia. The good news is that several large studies found that there are a number of lifestyle changes that one can do to have a healthier (memory! thinking!) brain in later years. Even if you are already in your 60s and 70s.

The evidence points to diet (e.g., Mediterranean style diet, ), exercise, and socializing being all important for brain health. In fact, it can result in keeping brains several years "younger" than in those with unhealthy lifestyles. Also, studies find that challenging your brain by learning something new, such as learning a new language or musical instrument or online cognitive training, is beneficial for the brain.

Adopting a lifestyle that promotes brain health is so very important, because it is NORMAL that as we age, there are brain changes, including brain shrinkage (volume of the brain). Therefore you want to slow down or delay these age related changes as much as possible. Researchers feel that adopting these lifestyle changes are so effective that they should be medically prescribed.

Excerpts from NPR: Trying to keep your brain young? A big new study finds these lifestyle changes help

Scientists have unveiled the strongest evidence yet that a combination of diet, exercise and brain training can improve thinking and memory in older Americans.

A study of more than 2,100 sedentary people in their 60s and 70s found that those who spent two years on the intensive regimen not only improved their mental abilities but appeared to reduce the usual declines associated with aging. ...continue reading "Lifestyle Changes That Benefit the Aging Brain"

Published on Leave a comment on Subtle Brain Changes From Heading Soccer Balls
Soccer ball Credit: Wikipedia

Many studies have discussed the short-term and long-term harm to the brain from both concussions and sub-concussions in athletes playing tackle football. But relatively little has been said about the possibility of similar harm from soccer. A recent study found that heading a soccer ball results in subtle brain changes, even when there isn't a concussion.

The well-done study of 15 adult male soccer players looked whether there are brain changes after a routine "heading" task (heading the ball 20 times in 20 minutes) and after a routine "kicking" task (the tasks were routine soccer exercises). Blood samples and MRIs of the brain were taken after each task, as well as cognitive function assessments.

There were subtle brain changes seen in the MRIs, as well as inflammatory markers present in the blood after the soccer heading task, but not after the kicking task. As the researchers concluded: "non-concussive impacts, specifically those administered in the form of a controlled SHT, can alter select markers of brain function, chemistry and microstructure in male soccer players." Additionally, "heading decreased tissue conductivity in 11 areas of white matter of the brain".

The big question is what does heading of soccer balls, many times over a lifetime, do to the brain? Increased rates of dementia?

Bottom line: Heading soccer balls, even when done as part of soccer practice, causes subtle changes in certain areas of the brain. Be cautious!

From Medical Xpress: Heading soccer balls can cause changes in the brain even without concussion or symptoms

Heading a soccer ball alters the brain, new research spearheaded by the University of Sydney has found, despite having no immediate impact on cognition. ...continue reading "Subtle Brain Changes From Heading Soccer Balls"

Published on Leave a comment on Living Near A Golf Course Increases Risk of Parkinson’s Disease

Many people think that living next to a golf course is wonderful, thinking that it's lots of open space. But... it also comes with exposure to all the pesticides used on golf course lawns (pesticides drift through the air to neighboring properties and also get into water). Unfortunately, pesticides can cause health harms, including Parkinson's disease.

A recent study found that the closer a person lives next to a golf course, the higher the incidence of Parkinson's disease. In fact, living within a mile of a golf course is associated with a 126% increased risk for Parkinson's disease. The biggest risk was for individuals living 1 to 3 miles from a golf course.

Additionally, drinking water from groundwater that includes a water source from a golf course was associated with an almost two-fold increased risk for Parkinson's disease (due to drinking water contamination).

While this observational study showed an association with Parkinson's disease, other studies also show that exposure to certain pesticides increases the risk of Parkinson's disease. Some of the pesticides linked to increase risk of Parkinson's disease: 2,4-D, chlorpyrifos, MCPP, maneb, paraquat, and rotenone. (Note that pesticides such as 2,4-D are also commonly found in feed and weed products.)

Another disturbing thing to keep in mind is that American golf courses use greater amounts and more pesticides, including pesticides that are banned in Europe, compared to European golf courses. Just think of weed-free carpet-like lawns as poison lawns.

Excerpts from Medical Xpress: Golf course proximity linked to higher Parkinson's disease risk

Barrow Neurological Institute and Mayo Clinic-led researchers report an association between living near golf courses and increased Parkinson's disease (PD) risk in a study published in JAMA Network Open. ...continue reading "Living Near A Golf Course Increases Risk of Parkinson’s Disease"

Published on Leave a comment on The Sugar Substitute Erythritol And the Brain’s Blood Vessels

Once again artificial sweeteners are in the news, and not in a good way. New research found that the sugar substitute erythritol, at a concentration typically found in an artificially sweetened beverage, has harmful effects on the small blood vessels of the brain.

Erythritol crosses the blood brain barrier and interacts with the brain's cerebrovasculature (the blood vessels in the brain, including the arteries, veins, and capillaries that supply blood and nutrients to the brain tissue). This study focused on the smallest blood vessels (microvascular) in the brain. And yes, found that the amount or erythritol in 1 diet beverage has adverse effects at a cellular level on these blood vessels.

This study was done in a lab setting (and not directly on humans), but research results match up with other studies on erythritol. Other studies already found that erythritol increases the risk of heart attacks, heart disease, strokes, as well as blood clot formation. This study's results give an explanation for why there is a increased risk of these brain vascular (blood vessel) events happening.

Erythritol is found in some beverages advertised as low or zero calorie (e.g., Monster Zero energy drinks, Blue Sky Zero Sugar soda, Red Bull Zero) and in some low calorie foods (e.g., Halo Top low-calorie ice cream). Read ingredient lists on labels!

From Medical Xpress: Major sugar substitute found to impair brain blood vessel cell function, posing potential stroke risk

Erythritol may impair cellular functions essential to maintaining brain blood vessel health, according to researchers at the University of Colorado Boulder. Findings suggest that erythritol increases oxidative stress, disrupts nitric oxide signaling, raises vasoconstrictive peptide production, and diminishes clot-dissolving capacity in human brain microvascular endothelial cells. ...continue reading "The Sugar Substitute Erythritol And the Brain’s Blood Vessels"