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Pesticides are harmful to developing brains, especially during pregnancy. A number of studies have already found that higher exposure to organophosphate pesticides during pregnancy is linked to poorer cognitive functioning and behavior problems in children. A recent University of California study actually looked at the brain activity in 95 teenagers while they were doing a number of mental tasks. Using advanced brain imaging, they found altered brain activity in those teens who had the highest organophosphate pesticide exposure prenatally. These teenagers live in Salinas Valley, California - an agricultural area with many farms.

The researchers point out that "Over 800 million pounds of pesticide active ingredients are applied in the United States each year, with organophosphates (OPs) the most commonly applied class of insecticides. Exposure to OP pesticides, which are endocrine-disrupting compounds, is widespread in the US population, including among pregnant women and children." [PLEASE NOTE: Conventional farming uses organophosphates. Organic farming does not allow the use of organophosphates.]

The main way people get exposed to organophosphate pesticides is diet - especially pesticide residues on fruits and vegetables. Also, if people live near farms where such pesticides are used, or live with a person who works on a farm. They bring home the pesticides on their clothes. People also breathe breathe in pesticides when they are applied on nearby farms or properties due to pesticide drift.

Chlorpyrifos is one example of an organophosphate pesticide. It is considered so dangerous to the developing fetus and children (lower IQs, neurological effects, behavioral effects) that the EPA was going to ban it in the United States. However, the Trump administration overruled the ban (chemical/pesticide lobbyists at work!). Since then, several states (NY, Hawaii, California) have enacted legislation to ban all use of chlorpyrifos in those states, but it will take several years for the bans to become fully in effect.

From Science Daily: Prenatal pesticide exposure linked to changes in teen's brain activity   ...continue reading "Certain Pesticides Linked to Altered Brain Activity In Teenagers"

A few weeks ago I posted research about the nutrient choline and discussed its importance for brain health. Now Dr. Emma Derbyshire in the United Kingdom has written a piece in the current issue of the journal BMJ Nutrition, Prevention & Health about the necessity of choline in the diet and the health dangers of this nutrient being neglected, especially in people following plant based or vegan diets.

Choline is an essential nutrient that cannot be produced by the body in amounts needed for human requirements. Good sources of choline are meat, dairy products, poultry, and eggs, and it appears that eggs (the egg yolks) are especially beneficial.

From Medical Xpress: Suggested move to plant-based diets risks worsening brain health nutrient deficiency

The momentum behind a move to plant-based and vegan diets for the good of the planet is commendable, but risks worsening an already low intake of an essential nutrient involved in brain health, warns a nutritionist in the online journal BMJ Nutrition, Prevention & Health.  ...continue reading "Don’t Neglect the Nutrient Choline"

For years there has been a debate about whether adding  fluoride to drinking water was a plus (less tooth decay) versus those who felt there were possible health problems from the fluoride.  Now the results of a Canadian study is raising serious concerns. The researchers followed 601 pregnant women from 6 cities in Canada, and found that pregnant women with higher levels of fluoride in their urine tended to have children with lower average IQs (which was measured at 3 or 4 years of age). As in the USA, some communities added fluoride to municipal drinking water, while others didn't.

The problem is that: "Fluoride crosses the placenta, and laboratory studies show that it accumulates in brain regions involved in learning and memory, and alters proteins and neurotransmitters in the central nervous system." Not good. This is why studies are being done.

The researchers concluded the study with these words: "In this prospective birth cohort study from 6 cities in Canada, higher levels of fluoride exposure during pregnancy were associated with lower IQ scores in children measured at age 3 to 4 years. These findings were observed at fluoride levels typically found in white North American women. This indicates the possible need to reduce fluoride intake during pregnancy." [Note: in this study, the effect appeared to be stronger in boys than girls.]

Just note that this was an observational study (found an association, not a definite cause), but other studies also find such an association. (One study conducted in Mexico found that higher prenatal fluoride exposure was linked to lower IQs in 4 to 6 year old children.) Of course more studies are needed.

But in the meantime, one can try to lower fluoride exposure (in water) during pregnancy. One way is to drink less black tea (has high levels of fluoride) and green tea (varying levels of fluoride). Also, if fluoride is added to tap water, to try to drink less of that and perhaps more unfluoridated bottled water that is in glass bottles (because plastic leaches, and has more microplastics in it).

From The Scientist: Fluoride Exposure During Pregnancy Linked to Lower IQ In Sons   ...continue reading "Fluoridated Drinking Water and Pregnancy"

Back in 2015 and 2016 some studies found a link between taking medicines that are anticholinergic and cognitive decline and dementia. Some examples of non-prescription anticholinergic medications are Chlor-Trimeton, Benadryl, Tavist, and Dimetapp. During this time a person also contacted me to report that his relative, who had Down's syndrome, had once participated in a study where he received cholinergic therapy, with the result that during the study he functioned better neurologically. Meanwhile I read several studies of older people that supported the result of a higher intake of foods with choline and better neurological functioning (e.g. verbal and visual memory).

A recent large study of men over a 4 year period found an association between a  higher intake of foods with choline (dietary choline) and better performance on several cognitive tests and lower risk of dementia. The research, which was conducted in Finland, found that the relationship seemed especially strong for a type of choline called phosphatidylcholine. Eggs (specifically the egg yolks) are a primary dietary source of phosphatidylcholine, and indeed, in the study, higher egg intake was associated with better performance on several measures, including verbal fluency, as well as lower risk of dementia.

Choline is an essential nutrient, found in some foods. Its role in the body is complex, but one of its roles is to produce acetylcholine, an important neurotransmitter for memory, mood, muscle control, and other brain and nervous system functions (NIH choline fact sheet). On the other hand, anticholinergic medications block the action of the neurotransmitter acetylcholine (which is involved with learning and memory). Anticholinergic medications include many common drugs, such as some antihistamines, sleeping aids, tricyclic antidepressants, medications to control overactive bladder, and drugs to relieve the symptoms of Parkinson’s disease.

What should one do? First, make sure to eat some foods rich in choline, especially eggs. The researchers themselves say that "consuming an adequate amount of foods high in choline may be an easy, effective, and affordable way to maintain cognitive functioning". Good sources of choline are meat, dairy products, poultry, and eggs - and it appears that eggs (the egg yolks) are especially beneficial. Second, one should also try to avoid non-prescription and prescription medicines known to be anti-cholinergic. For example switch from allergy medicines diphenhydramine or chlorpheniramine (Chlor-Trimeton) to one that isn't anticholinergic. [See list.]

From Science Daily: Dietary choline associates with reduced risk of dementia  ...continue reading "The Choline In Eggs Is Beneficial For the Brain"

Moderation seems best for so many things in life. And apparently this may also be true for a person's cholesterol levels. In a large study researchers found that having low levels of LDL cholesterol (below 70 mg/dL) significantly increased the risk of hemorrhagic stroke (intracerebral hemorrhage).Typically, lowering LDL (low-density lipoprotein) cholesterol is recommended as a way to reduce the risk of a heart attack or ischemic stroke, but several studies now confirm this very low LDL cholesterol - hemorrhagic stroke association.

The study was led by Pennsylvania State University researcher Xiang Gao, but conducted over a 9 year period in an industrial area in northern China. The 96,043 participants had their LDL cholesterol levels measured 4 times over that period. The researchers didn't find any increased risk of hemorrhagic stroke when LDL levels were above 70 mg/dL.

From Medical Xpress: Cholesterol that is too low may boost risk for hemorrhagic stroke

Current guidelines recommend lowering cholesterol for heart disease risk reduction. New findings indicate that if cholesterol dips too low, it may boost the risk of hemorrhagic stroke, according to researchers.  ...continue reading "Can Cholesterol Levels Go Too Low?"

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Do you routinely work more than 10 hours a day at your job? Uh-oh. A large study conducted in France found that individuals working long hours had a 29% greater risk of stroke, and those working long hours for 10 years or more had a 45% greater risk of stroke. What exactly are long working hours? The study defined long working hours (LWH) as working more than 10 hours daily for at least 50 days per year.

The researchers looked at people who had full-time jobs, and did not separate out types of strokes - both ischemic and hemorrhagic strokes were lumped together in this study. Another interesting finding was that the risk for stroke was greater among people under the age of 50 who reported long working hours for more than 10 years. And this association had a "lower effect for owners, chief executive officers, professionals, and farmers" - all occupations where people had greater control over decisions during their days.

Studies from other countries found a similar association. For example, in Japan, 60% of death from over-work (called karoshi) cases who received worker compensation died of stroke.

From Science Daily: Long work hours associated with increased risk of stroke  ...continue reading "Long Work Hours Associated With Increased Stroke Risk"

There has been a lot of discussion recently about whether older adults form new neurons in the brain. Neurons are specialized cells transmitting nerve impulses in the brain - they are nerve cells. In other words, if elderly people form new neurons in the brain, then this is excellent news for brain function. This means we can look for ways to enhance neurogenesis (formation of new neurons) and slow or prevent cognitive decline, whether in diseases such as Alzheimer's or normal age-related cognitive declines. Because yes, it is normal to have age-related declines, but some people have more declines while others far, far less.

Researchers at the University of Illinois at Chicago studied the hippocampus of 18 elderly brains (mean age 90.6 years!) after death (post-mortem). They found both new neural stem cells (neural progenitor cells) and developing neurons in each person's brain, but the numbers varied a lot between the brains. For example, brains with evidence of Alzheimer's disease and cognitive impairments had significantly fewer developing neurons than those without cognitive declines.

These results go hand in hand with studies showing a number of known age related brain changes, such as the volume of the brain shrinking a little as we age (this is considered normal). Studies find that there are ways to slow down this shrinkage such as good nutrition (including nuts, fruits and vegetables, coffee or tea containing caffeine, eating seafood), physical activity, exercise, having mentally stimulating activities. Also, avoiding medicines with anticholinergics, and avoiding air pollution and an unhealthy Western style diet (highly processed foods, low fiber, lots of meat).

From Medical Xpress: New neurons form in the brain into the tenth decade of life, even in people with Alzheimer's  ...continue reading "New Neurons Form In the Brains Of Older Adults"

A number of studies have found that a poor sense of smell in older adults is linked to health problems (especially Parkinson's disease and dementia) and death. Now a recent study found that a poor sense of smell in older adults is associated with an almost 50% increase in their risk of dying within 10 years—especially in individuals reporting good health. In other words, a poor sense of smell is an early sign of deteriorating health, even when it is not apparent yet to the person.

Researchers at  the Michigan State Univ. College of Human Medicine  followed 2,289 persons (aged 71 to 82) for 13 years. The generally healthy persons took a smell test of 12 common odors (e.g. onion, soap, gasoline, lemon, chocolate and rose) at the start of the study, and were scored as having good, moderate, or poor sense of smell. After 13 years 1,211 of them had died. The researchers then looked to see if there was any association between scores on the smell test and their risk of death at various points over the 13 years.

No association was found at the three- or five-year mark of the study. But those with a poor sense of smell had a 46 percent higher risk of dying by 10 years and a 30 percent higher risk by 13 years, when compared with the older adults with a good sense of smell. The researchers believe the risk was lower at 13 years because so many of the participants had already died - whether their ability to smell was initially good or poor. So how to interpret the study results? It appears that a poor sense of smell may be a sensitive early sign of deteriorating health, even when it is not apparent yet.

From Medical Xpress: Poor sense of smell associated with nearly 50 percent higher risk for death in 10 years  ...continue reading "Is A Poor Sense of Smell In Older Adults A Sign of Deteriorating Health?"

Great news for those who don't exercise at government recommended guideline levels of 150 minutes of moderate to vigorous activity per week. Which may be most of us, perhaps? Hmmm? A recent study found that even light intensity exercise is beneficial to the brain.

The study of 2354 persons (average age 53 years) in Framingham, Massachusetts, found that each additional hour spent in light-intensity physical activity was associated with a larger brain volume - equivalent to approximately 1.1 years less brain aging. Thus, the more activity, the more beneficial. In general, total cerebral brain volume declines at a rate of 0.2% per year after age 60 years - so slowing this process down is desirable.

Both physical activity levels and steps per day was looked at, and both were beneficial to brain volume. The study found that walking 10 ,000 or more steps per day was associated with higher brain volume when compared with persons who walked fewer than 5000 steps per day. But even 7500 steps was better for the brain than 5000 steps. How did they measure brain volume? With brain MRI imaging. 

This study found that light exercise is beneficial to the brain, specifically the brain volume - but note that these benefits are from levels below official recommended guidelines. The US Department of Health and Human Services (HHS) 2018 Physical Activity Guidelines for Americans state that 150 or more minutes of moderate to vigorous physical activity (MVPA) per week is recommended for substantial health benefits (but they also said that "some physical activity is better than none"). In other words, get off your butt and move - any activity and exercise is better than none!

From Science News: Light, physical activity reduces brain aging

Incremental physical activity, even at light intensity, is associated with larger brain volume and healthy brain aging ...continue reading "Light Physical Activity Is Beneficial to the Brain"

Another study found benefits from eating nuts - this time an association between frequently eating nuts and better brain functioning in older adults. The study was done in China and was part of a long-term nutrition and cognitive function study of 4822 adults (aged 55+ years). With aging, it is normal to have some decline in brain functioning, but the researchers said that high nut consumers had much less decline - that the more nuts consumed, the less decline (an inverse relationship).

The article below makes some grand claims ("could improve their cognitive function by up to 60 per cent") for a study that found an association between long-term nut consumption of more than 10 grams (about 1/8 cup) daily and cognitive health, but this doesn't prove it. Perhaps people who eat nuts also eat other foods or do other things that are beneficial for brain functioning. But ... the good news is that eating nuts frequently appears to be beneficial. So eat and enjoy.

By the way, peanuts are not nuts - they are legumes (also beans and peas) - but they have numerous health benefits, and were counted as nuts in this study. Common tree nuts are cashews, almonds, walnuts, hazelnuts, pecans, macadamia nuts, pine nuts, pistachios, chestnuts, lichee nuts, and Brazil nuts. [See all posts on health benefits of nuts.]

From Science Daily: A nutty solution for improving brain health

Long-term, high nut consumption could be the key to better cognitive health in older people according to new research from the University of South Australia.  ...continue reading "Another Reason To Eat Nuts Frequently"