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Image result for dark chocolate Two new studies finding benefits from chocolate consumption: dark chocolate boosting athletic performance (in cycling), and long-term chocolate consumption (several times a week for many years) linked to better cognitive function. From Medical Xpress:

Eating chocolate improves cognitive function, study finds

People who ate chocolate at least once a week performed better on multiple cognitive tasks, compared to those who ate chocolate less frequently, according to a new study by researchers at the University of Maine, University of South Australia and Luxembourg Institute of Health that has garnered international attention. 

With age, education, gender, age and race controlled, cognitive tasks were related to following domains, each measured by multiple tests: Visual-Spatial Memory and Organization, Working Memory, Abstract Verbal Reasoning, Scanning and Tracking, and overall cognitive functioning. The 968 participants ages 23–98 in the study came from the Maine-Syracuse Longitudinal Study, directed by Elias, which has tracked more than 1,000 people over 35 years.

The researchers hypothesized that regular intake of cocoa flavanols may be one of several mechanism explaining the cognitive benefits of chocolate. In addition, compared to those who never or rarely ate chocolate, those who ate chocolate weekly had higher total and LDL cholesterol, but lower glucose levels. Hypertension and Type 2 diabetes also were lower in regular chocolate consumers than in nonconsumers. 

From Medical Xpress: Eating dark chocolate as a daily snack could help boost athletic performance, study suggests

Dark chocolate has already been hailed for its positive effects on cardiovascular health – and now a study undertaken at London's Kingston University has found the tasty treat could help give sports enthusiasts an extra edge in their fitness training. A team led by postgraduate research student Rishikesh Kankesh Patel discovered that dark chocolate provides similar benefits to beetroot juice, now taken regularly by elite athletes after studies showed it can improve performance. "Beetroot juice is rich in nitrates, which are converted to nitric oxide in the body. This dilates blood vessels and reduces oxygen consumption – allowing athletes to go further for longer," Mr Patel explained.

The Kingston University team wanted to find out whether dark chocolate could provide a similar boost, as it contains a substance called epicatechin – a type of flavanol found in the cacao bean, that also increases nitric oxide production in the body.

To test the theory, Mr Patel carried out a study with a group of nine amateur cyclists.....After undergoing initial fitness tests to establish a baseline for comparison, the participants were then split into two groups. The first group was asked to replace one of its normal daily snacks with 40 g of a dark chocolate known to be rich in flavanols for a fortnight, while the other participants substituted 40 g of white chocolate for one of their daily snacks as a control.

The effects of the athletes' daily chocolate consumption were then measured in a series of cycling exercise tests in the sports performance laboratory at the University's Penrhyn Road campus....The study, which has now been published in the Journal of the International Society of Sports Nutrition, found that after eating dark chocolate, the riders used less oxygen when cycling at a moderate pace and also covered more distance in a two-minute flat-out time trial.

This is huge. Decades long advice dietary advice to Americans was wrong. New research finds that the medical advice to replace saturated fat in the diet with vegetable oils rich with linoleic acid lowers cholesterol, but does not lead to a lower risk of death from coronary heart disease or other causes. It may even lead to increased rates of death from coronary heart disease, and cardiovascular disease (2013 study). Vegetable oils rich in linoleic acid are corn oil, sunflower oil, safflower oil, cottonseed oil, and soybean oil.

Other recent articles written on this topic have pointed out that research evidence opposing the prevailing medical view of what is "heart healthy" (low-fat foods, and substitute vegetable oil for butter) was suppressed for decades and the researchers ridiculed. In the past few years a number of other studies have found health benefits from whole fat foods (such as high-fat dairy foods) and not from low-fat or zero fat foods or vegetable oils. From Medical Xpress:

Researchers unearthed more evidence that replacing butter with vegetable oils does not decrease risk of heart disease

A research team led by scientists at the UNC School of Medicine and the National Institutes of Health has unearthed more evidence that casts doubt on the traditional "heart healthy" practice of replacing butter and other saturated fats with corn oil and other vegetable oils high in linoleic acid. The findings, reported today in the British Medical Journal, suggest that using vegetable oils high in linoleic acid might be worse than using butter when it comes to preventing heart disease, though more research needs to be done on that front.

This latest evidence comes from an analysis of previously unpublished data of a large controlled trial conducted in Minnesota nearly 50 years ago, as well as a broader analysis of published data from all similar trials of this dietary intervention. The analyses show that interventions using linoleic acid-rich oils failed to reduce heart disease and overall mortality even though the intervention reduced cholesterol levels. In the Minnesota study, participants who had greater reduction in serum cholesterol had higher rather than lower risk of death.

Along with corn oil, linoleic acid-rich oils include safflower oil, soybean oil, sunflower oil, and cottonseed oil. The belief that replacing saturated fats with vegetable oils improves heart health dates back to the 1960s, when studies began to show that this dietary switch lowered blood cholesterol levels. Since then, some studies, including epidemiological and animal studies, have suggested that this intervention also reduces heart attack risk and related mortality. In 2009, the American Heart Association reaffirmed its view that a diet low in saturated fat and moderately high (5-10 percent of daily calories) amounts of linoleic acid and other omega-6 unsaturated fatty acids probably benefits the heart.

However, randomized controlled trials - considered the gold standard for medical research - have never shown that linoleic acid-based dietary interventions reduce the risk of heart attacks or deaths. The largest of these trials, the Minnesota Coronary Experiment (MCE), was conducted by researchers at the University of Minnesota between 1968 and 1973. It enrolled 9,423 patients in six state mental hospitals and one state-run nursing home.....The investigators reported then that a switch to corn oil from butter and other saturated fats did lower cholesterol levels but made no difference in terms of heart attacks, deaths due to heart attacks, or overall deaths.....But they also found that.... the corn oil group had almost twice the number of heart attacks as the control group.

In a much-cited study published in 2013, however, Ramsden, Zamora and colleagues were able to recover unpublished data from a smaller trial, the Sydney Diet Heart Study, and there they also found more cases of heart disease and death among patients who received a linoleic acid intervention (safflower oil), compared to controls.

Why linoleic acid-containing oils would lower cholesterol but worsen or at least fail to reduce heart attack risk is a subject of ongoing research and lively debate. Some studies suggest that these oils can - under certain circumstances - cause inflammation, a known risk factor for heart disease. There is also some evidence they can promote atherosclerosis when the oils are chemically modified in a process called oxidation.

There is increasing concern over phthalates and BPA and their effects on human health. It turns out that a big source of phthalates (which are known endocrine disruptors) in humans may be fast food.

A new study looked at fast food consumption by  8877 people and found that those who reported eating more of it in the past 24 hours had urinary phthalate levels as much as 40 percent higher than those who had eaten no fast food in the 24 hours before testing. In fact, it was dose-response relationship between fast food intake and exposure to phthalates - the more fast food, the higher the level of phthalates.

The researchers did not find an association between total fast food consumption and BPA. However, they did find an  association between fast food meat intake and BPA,  which corresponds to the small but growing evidence from other studies suggesting that hamburgers may be a source of BPA exposure.

These findings are of concern to all of us because phthalates and bisphenol A (BPA) are widely used industrial chemicals that may adversely impact human health. Studies detect phthalates in 98% of the US population. They are found in a wide variety of products (including plastics and personal care products), and can enter the human body via ingestion, inhalation, and absorption through the skin.

How are we exposed to them in fast food? Phthalates and BPA are typically found in food packaging and some leaches out into food. Some can also leach into food from dairy product tubing, in lid gaskets, food preparation gloves, conveyor belts, etc. Thus we ingest phthalates and BPA when we consume processed or packaged food. Fast food may be an especially important source of exposure to phthalates and BPA because it is highly processed, packaged, and handled.

Studies have demonstrated that the phthalates DEHP and DiNP are endocrine (hormone) disruptors, and that human exposure has been associated with adverse reproductive, neurobehavioral, and respiratory health effects. BPA is also an endocrine disruptor. We are all being exposed numerous ways, but the lower the levels, the better.

The good news is that once in the body, phthalates and BPA are quickly metabolized and excreted in urine, with elimination half-lives of less than 24 hours. Thus you can quickly reduce the levels in your body. And you should try.

From Science Daily: Fast food may expose consumers to harmful chemicals called phthalates

People who reported consuming more fast food in a national survey were exposed to higher levels of potentially harmful chemicals known as phthalates, according to a study published by researchers at Milken Institute School of Public Health (Milken Institute SPH) at the George Washington University.

"People who ate the most fast food had phthalate levels that were as much as 40 percent higher," says lead author Ami Zota, ScD, MS, an assistant professor of environmental and occupational health at Milken Institute SPH. "Our findings raise concerns because phthalates have been linked to a number of serious health problems in children and adults."Phthalates belong to a class of industrial chemicals used to make food packaging materials, tubing for dairy products, and other items used in the production of fast food. Other research suggests these chemicals can leach out of plastic food packaging and can contaminate highly processed food.

Zota and her colleagues looked at data on 8,877 participants who had answered detailed questions about their diet in the past 24 hours, including consumption of fast food. These participants also had provided researchers with a urinary sample that could be tested for the breakdown products of two specific phthalates--DEHP and DiNP.

Zota and her colleagues found that the more fast food participants in the study ate the higher the exposure to phthalates. People in the study with the highest consumption of fast food had 23.8 percent higher levels of the breakdown product for DEHP in their urine sample. And those same fast food lovers had nearly 40 percent higher levels of DiNP metabolites in their urine compared to people who reported no fast food in the 24 hours prior to the testing. The researchers also discovered that grain and meat items were the most significant contributors to phthalate exposure. Zota says the grain category contained a wide variety of items including bread, cake, pizza, burritos, rice dishes and noodles.

In addition, the researchers also looked for exposure to another chemical found in plastic food packaging--Bisphenol A or BPA. Researchers also believe exposure to BPA can lead to health and behavior problems, especially for young children. This study found no association between total fast food intake and BPA. However, Zota and her colleagues found that people who ate fast food meat products had higher levels of BPA than people who reported no fast food consumption.

Another article commenting that increasing the amount of dietary fiber eaten by people eating a typical Western diet (which is low in fiber) will improve their gut microbiome (community of microbes). Research is finding that the added dietary fiber is food (nutrition) for microbes in the gut, and eating additional fiber daily will help restore or increase bacterial diversity, which then should lead to health benefits. Note: Easy ways to increase dietary fiber are increasing intake of whole grains, legumes, nuts, seeds, fruits, and vegetables. Think of food writer Michael Pollan's advice: "Eat food. Not too much. Mostly plants."

Researchers feel that fiber intake needs to be increased to more than current dietary guidelines, and that beneficial effects to the microbiome starts to occur rapidly (within 2 weeks) of changing to a higher fiber diet. This post from January 21, 2016 discussed the Sonnenburg research on gut microbe depletion (from a low fiber diet), and this April 28, 2015 post discussed the O'Keefe research (changing the diet has big effect on colon cancer risk) - both studies are mentioned below. See the page Feeding Your Gut Microbes for more information. From Science Daily:

Can more fiber restore microbiome diversity?

Scientists are pushing to restore human health in Western countries by changing our diet to restore the microbial species lost over the evolution of Western diet. Researchers advocate for strategically increasing dietary fiber intake as one path forward in regaining microbial biodiversity.

Insufficient nutrients for our gut microbes have been linked to a loss of certain beneficial bacterial species in industrialized societies and are likely impacting our immunological and metabolic health, although more data is needed. For example, most Westerners consume half of the amount of dietary fiber recommended by dietary guidelines, which nutritionists refer to as the "fiber gap," which is a problem because dietary fiber is the primary source of nutrition (e.g., carbohydrates) accessible to gut bacteria in humans.

"The idea to boost fiber levels is not new," says Jens Walter of the University of Alberta, Canada. "However, depletion of the microbiome adds a new perspective to this low-fiber Western diet that we are currently eating." Earlier this year, Stanford University's Justin Sonnenburg found that mice fed a typical Western diet (high in fat and carbohydrates and low in fiber) transferred a lower diversity of beneficial microbial species to future generations. The re-introduction of the microbes' preferred fiber at that stage did not result in a return of some (good) species, indicating that extinctions had occurred in only a few generations.

Walter and co-author Edward Deehan, his PhD student, are concerned that a dramatic shift away from a diet similar to the one under which the human-microbiome symbiosis evolved is a key factor in the rise of non-communicable disorders like obesity. "There is a lot of epidemiological evidence that fiber is beneficial, and food products containing dietary fiber have FDA-approved health claims for both colon cancer and coronary heart disease. There is also quite a bit of clinical evidence (although it is less consistent)," Walter says. "The most pressing issue at the moment that neither consumption of fiber in society nor the doses used in clinical research are high enough."

People living in non-industrialized societies have an average intake of fiber that is much higher than the low norms of Western societies. The authors note the recent work from the Stephen J.D. O'Keefe lab in Nature Communications in which modern African-Americans were given a traditional South-African diet that contained 55 grams of daily dietary fiber and had improved markers for colon cancer within two weeks.

Coffee consumption overall seems to be beneficial to health in various ways, such as lowering the risk of colorectal cancer. But there are times one should limit how much one drinks, such as during the  preconception period for both the male and female, and also during pregnancy, to lower the risk of miscarriage.

From Science Daily: Coffee consumption linked to decreased risk of colorectal cancer

Researchers have found that coffee consumption, including decaf, instant and espresso, decreases the risk of colorectal cancer. Moreover, these benefits increase the more coffee you drink. The study examined over 5,100 men and women who had been diagnosed with colorectal cancer within the past six months, along with an additional 4,000 men and women with no history of colorectal cancer to serve as a control group. Participants reported their daily consumption of boiled (espresso), instant, decaffeinated and filtered coffee, as well as their total consumption of other liquids.....

The data showed that even moderate coffee consumption, between one to two servings a day, was associated with a 26 percent reduction in the odds of developing colorectal cancer after adjusting for known risk factors. Moreover, the risk of developing colorectal cancer continued to decrease to up to 50 percent when participants drank more than 2.5 servings of coffee each day. The indication of decreased risk was seen across all types of coffee, both caffeinated and decaffeinated.

Coffee contains many elements that contribute to overall colorectal health and may explain the preventive properties. Caffeine and polyphenol can act as antioxidants, limiting the growth of potential colon cancer cells. Melanoidins generated during the roasting process have been hypothesized to encourage colon mobility. Diterpenes may prevent cancer by enhancing the body's defense against oxidative damage. "The levels of beneficial compounds per serving of coffee vary depending on the bean, roast and brewing method," said first author Stephanie Schmit, PhD, MPH. 

Colorectal cancer is the third most common cancer that is diagnosed in both men and women in the United States, with nearly five percent of men and just over four percent of women developing the disease over their lifetime. The American Cancer Society (ACS) estimates that in the United States, over 95,000 new cases of colon cancer and 39,000 new cases of rectal cancer will be diagnosed in this year alone.

Both males and females should limit coffee consumption in the preconception period to no more than 2 caffeinated drinks daily to lower the female's risk of miscarriage. From Medscape:

Even Men Need to Cut Back on Coffee Before Pregnancy

Women already know they need to cut back on coffee during pregnancy, if not sooner, to lower the risk of miscarriage. But a new study suggests the men in their lives need to limit caffeine too. Pregnant women who had more than two caffeinated drinks a day while trying to conceive had a 74% higher risk of miscarriage than their peers who drank less coffee, tea, soda and energy drinks, the study found.

When their husbands and boyfriends had more than two caffeinated drinks a day during the preconception phase, however, these pregnant women ended up with almost the same increased risk of miscarriage they would get from drinking coffee or soda themselves...."We did not find drinking one to two daily caffeinated beverages to increase the risk of miscarriage." Scientists aren't sure how caffeine contributes to miscarriage, but it's possible it affects egg or sperm production, implantation of the fertilized egg, or the ability of the embryo to grow in the uterus.

To assess how lifestyle choices may influence miscarriage risk, Louis and colleagues followed 344 couples in Texas and Michigan through the first seven weeks of pregnancy....Overall, 98 women, or 28%, experienced a miscarriage during the study, as reported March 24 in the journal Fertility and Sterility. Women 35 or older had nearly double the miscarriage risk of younger women, the study found. When women took daily multivitamins, their miscarriage risk was 55% lower than for their peers who didn't do this.

One surprise in the study is that researchers didn't find an increased miscarriage risk associated with smoking or alcohol, however. This doesn't mesh with previous research, noted Dr. Jeffrey Goldberg, a reproductive health researcher at Cleveland Clinic in Ohio who wasn't involved in the study. 

 A number of recent studies looked at vitamin D and various diseases. All showed benefits of higher vitamin D levels in the blood: lower rates of cancer incidence, improved heart function in those with heart failure, lower rates of leukemia incidence, lower rates of breast cancer, and less aggressive breast and prostate cancer. However, one study found no benefits to vitamin D supplementation during pregnancy and the child's asthma risk. Older studies found low levels of vitamin D linked to higher risk of premenopausal breast cancer, and also to thicker melanomas at diagnosis (the thinner the melanoma, the better the prognosis).

Everyone agrees that sunshine is an excellent source of vitamin D, but there is still disagreement over what are the best daily vitamin D supplement dosages, or even what are optimal levels of vitamin D in the blood (measured as serum 25-hydroxyvitamin D or 25(OH)D). In 2010, the Institute of Medicine (IOM) concluded that levels lower than 12 ng/ml represented a vitamin D deficiency and recommended a target of 20 ng/ml, which could be met in most healthy adults (ages 19 to 70) with 600 International Units of vitamin D each day. Since then most researchers have argued for higher blood serum levels: most agreeing that over 30 ng/ml is best, while some advocating 50 ng/ml or more. But even what's too high (and could cause problems) is debated. Many vitamin D supporters now advocate taking 800 to 1,000 IUs of vitamin D daily (some say up to 4000 IUs daily is OK). Remember to look for vitamin D3 supplements, not D2.

This study found that higher levels of vitamin D (measured as serum 25(OH)D) are better, with 25(OH)D concentrations of at least 40 ng/ml best to reduce cancer risk (all types of cancer). From Medical Xpress: Higher levels of vitamin D correspond to lower cancer risk, researchers say

Researchers at University of California, San Diego School of Medicine report that higher levels of vitamin D - specifically serum 25-hydroxyvitamin D - are associated with a correspondingly reduced risk of cancer. The findings are published in the April 6, online issue of PLOS ONE.

Garland and his late brother, Frank, made the first connection between vitamin D deficiency and some cancers in 1980 when they noted populations at higher latitudes (with less available sunlight) were more likely to be deficient in vitamin D, which is produced by the body through exposure to sunshine, and experience higher rates of colon cancer. Subsequent studies by the Garlands and others found vitamin D links to other cancers, such as breast, lung and bladder.

The new PLOS ONE study sought to determine what blood level of vitamin D was required to effectively reduce cancer risk....The only accurate measure of vitamin D levels in a person is a blood test....Cancer incidence declined with increased 25(OH)D. Women with 25(OH)D concentrations of 40 ng/ml or greater had a 67 percent lower risk of cancer than women with levels of 20 ng/ml or less.

Garland does not identify a singular, optimum daily intake of vitamin D or the manner of intake, which may be sunlight exposure, diet and/or supplementation. He said the current study simply clarifies that reduced cancer risk becomes measurable at 40 ng/ml, with additional benefit at higher levels. "These findings support an inverse association between 25(OH)D and risk of cancer," he said, "and highlight the importance for cancer prevention of achieving a vitamin D blood serum concentration above 20 ng/ml, the concentration recommended by the IOM for bone health."

From Science Daily: Vitamin D improves heart function, study finds

A daily dose of vitamin D3 improves heart function in people with chronic heart failure, a five-year research project has found. The study involved more than 160 patients who were already being treated for their heart failure using proven treatments including beta-blockers, ACE-inhibitors and pacemakers.

Participants were asked to take vitamin D3 or a dummy (placebo) tablet for one year. Those patients who took vitamin D3 experienced an improvement in heart function which was not seen in those who took a placebo....In the 80 patients who took Vitamin D3, the heart's pumping function improved from 26% to 34%. In the others, who took placebo, there was no change in cardiac function.

Disappointing results. From Medscape: Vitamin D Disappoints: Prenatal Supplementation and Childhood Asthma

Two recent clinical trials examined maternal supplementation with vitamin D and postpregnancy offspring outcomes for asthma and wheezing....However, with respect to preventing asthma in offspring, there is no clear evidence for vitamin D supplementation in pregnant women.

From PLOS ONE: Vitamin D Deficiency at Melanoma Diagnosis Is Associated with Higher Breslow Thickness

Vitamin D deficiency at the time of melanoma diagnosis is associated with thicker tumours that are likely to have a poorer prognosis. Ensuring vitamin D levels of 50 nmol/L or higher in this population could potentially result in 18% of melanomas having Breslow thickness of <0.75 mm rather than ≥0.75 mm.

Reported in 2013. From Medical Express: Low vitamin D levels linked to high risk of premenopausal breast cancer

A prospective study led by researchers from the University of California, San Diego School of Medicine has found that low serum vitamin D levels in the months preceding diagnosis may predict a high risk of premenopausal breast cancer. The study of blood levels of 1,200 healthy women found that women whose serum vitamin D level was low during the three-month period just before diagnosis had approximately three times the risk of breast cancer as women in the highest vitamin D group. 

A 2011 meta-analysis by Garland and colleagues estimated that a serum level of 50 ng/ml is associated with 50 percent lower risk of breast cancer. While there are some variations in absorption, those who consume 4000 IU per day of vitamin D from food or a supplement normally would reach a serum level of 50 ng/ml.

A study by researchers showing troubling effects from certain pesticides (especially a class of fungicides) raises all sorts of questions: What is the long-term effect of chronic low doses of these fungicides in the foods we eat? How much of these chemicals are we getting exposed to? The Univ. of North Carolina researchers studied the effect of 294 chemicals (all common food-use pesticides or other environmental chemicals) on "mouse cortical neurons" (mouse brain cells). They found that one group of chemicals, which they referred to as "cluster 2", "mimics brain disorders" such as autism, advanced age, Alzheimer's, Parkinson's disease, and other neurodegenerative disorders. The chemicals (all pesticides, and mainly fungicides) causing these effects are: fenamidone, pyraclostrobin, famoxadone, trifloxystrobin, fenpyroximate, azoxystrobin, fluoxastrobin pyridaben and rotenone. Even though this study was done on mouse cortical neurons (in vitro), it is meaningful because of the similarities with human brain cells.

Very little is known about human exposure to these chemicals (how much is our exposure?) and their effects on humans, but the data suggest effects similar to that in neurological disorders. The researchers point out that many of the chemical residues in this cluster were found on conventionally raised foods, especially leafy green vegetables, and were detected at relatively high levels, especially pyraclostrobin. Most of these fungicides only came into use after 2000 and usage of these fungicides has been increasing in the U.S, with the exception of pyridaben (decreasing use) and rotenone (very low use). "These data suggest significant human exposure potential to many of the chemicals in cluster 2".

They point out that these fungicide residues have not been detected on organically produced foods (EPA and USDA data), which suggests a way to minimize exposure. None of these chemicals can be used by organic farmers in the U.S. Possible exposure is also from gardens and lawns (if used), contaminated water, and for farm workers in conventional agriculture. From Science Daily:

Could new class of fungicides play a role in autism, neurodegenerative diseases?

Scientists at the UNC School of Medicine have found a class of commonly used fungicides that produce gene expression changes similar to those in people with autism and neurodegenerative conditions, including Alzheimer's disease and Huntington's disease.

Mark Zylka, PhD, senior author of the study and associate professor of cell biology and physiology at UNC, and his team exposed mouse neurons to approximately 300 different chemicals.... "Based on RNA sequencing, we describe six groups of chemicals," Zylka said. "We found that chemicals within each group altered expression in a common manner. One of these groups of chemicals altered the levels of many of the same genes that are altered in the brains of people with autism or Alzheimer's disease." Chemicals in this group included the pesticides rotenone, pyridaben, and fenpyroximate, and a new class of fungicides that includes pyraclostrobin, trifloxystrobin, fenamidone, and famoxadone. Azoxystrobin, fluoxastrobin, and kresoxim-methyl are also in this fungicide class.

"We cannot say that these chemicals cause these conditions in people," Zylka cautioned. "Many additional studies will be needed to determine if any of these chemicals represent real risks to the human brain." Zylka, a member of the UNC Neuroscience Center, and his group found that these chemicals reduced the expression of genes involved in synaptic transmission -- the connections important for communication between neurons. If these genes are not expressed properly, then our brains cannot function normally. Also, these chemicals caused an elevated expression of genes associated with inflammation in the nervous system. This so-called neuroinflammation is commonly seen in autism and neurodegenerative conditions.

The researchers also found that these chemicals stimulated the production of free radicals -- particles that can damage the basic building blocks of cells and that have been implicated in a number of brain diseases. The chemicals also disrupted neuron microtubules. "Disrupting microtubules affects the function of synapses in mature neurons and can impair the movement of cells as the brain develops," Zylka said. "We know that deficits in neuron migration can lead to neurodevelopmental abnormalities. We have not yet evaluated whether these chemicals impair brain development in animal models or people."

Jeannie T. Lee, MD, PhD, professor of genetics at Harvard Medical School and Massachusetts General Hospital, who was not involved in this research, said, "This is a very important study that should serve as a wake-up call to regulatory agencies and the general medical community. The work is timely and has wide-ranging implications not only for diseases like autism, Parkinson's, and cancer, but also for the health of future generations. I suspect that a number of these chemicals will turn out to have effects on transgenerational inheritance."

Zylka's group also analyzed information from the U.S. Geological Survey, which monitors countywide pesticide usage, as well as the Food and Drug Administration and the U.S. Department of Agriculture, which test foodstuffs yearly for pesticide residues. Of the chemicals Zylka's team studied, only the usage of pyridaben has decreased since 2000. Rotenone use has remained the same since 2000. However, the use of all the fungicides in this group has increased dramatically over the past decade.

Indeed, a study from the Environmental Protection Agency found that pyraclostrobin is found on foods at levels that could potentially affect human biology, and another study linked pyraclostrobin usage to honeybee colony collapse disorder. The pesticide rotenone was previously implicated in Parkinson's disease through replicated animal experiments and through human epidemiological studies.....Previous work has also shown that a single dose of the fungicide trifloxystrobin reduced motor activity for several hours in female rats and for days in male rats. Disrupted motor function is a common symptom of Parkinson's disease and other neurological disorders. The related fungicide picoxystrobin impaired motor activity in rats at the lowest dose tested.

Zylka added, "The real tough question is: if you eat fruits, vegetables or cereals that contain these chemicals, do they get into your blood stream and at what concentration? That information doesn't exist." Also, given their presence on a variety of foodstuffs, might long term exposure to these chemicals -- even at low doses -- have a cumulative effect on the brain?

Zylka noted that conventionally grown leafy green vegetables such as lettuce, spinach, and kale have the highest levels of these fungicides. But due to each chemical's effectiveness at reducing fungal blights and rust, crop yields have increased and farmers are expanding their use of these chemicals to include many additional types of food crops.

Zylka's team hopes their research will encourage other scientists and regulatory agencies to take a closer look at these fungicides and follow up with epidemiological studies. "Virtually nothing is known about how these chemicals impact the developing or adult brain," Zylka said. "Yet these chemicals are being used at increasing levels on many of the foods we eat."

Applying fungicide to apple orchard. Credit: Univ. of Kentucky Agriculture Extension

Nice summary article about the known benefits of nuts and seeds, and the nutrients they contain. Bottom line: all nuts and seeds are beneficial to health. It's best to eat a variety of nuts, and eat some nuts daily or at least a few times a week. A typical serving is 1/4 cup or small handful of nuts. Go to the article for the complete nut and seed list and a nut and seed nutrient chart. From Today's Dietician:

The Wonders of Nuts and Seeds

Nuts and seeds have been part of the human diet since Paleolithic times. A few nuts, such as almonds and walnuts, and seeds, namely flax and chia, get most of the glory, but the fact is each nut and seed brings something beneficial to the table. While exact nutrient compositions vary, nuts and seeds are rich sources of heart-healthy fats, fiber, plant protein, essential vitamins and minerals, and other bioactive compounds, including an array of phytochemicals that appear to have antioxidant and anti-inflammatory properties.

A wealth of data from prospective observational studies and clinical trials suggest that tree nut consumption reduces the risk of several chronic diseases, including cardiovascular disease (CVD), type 2 diabetes, and some forms of cancer. Moreover, there may be benefits for cognitive health. Adding support to these findings is research suggesting that incorporating tree nuts in the diet lowers the risk of conditions that contribute to disease, such as hypertension, high cholesterol, insulin resistance, abdominal obesity, endothelial dysfunction, oxidative stress, and inflammation. Various components of nuts, such as heart-healthy monounsaturated and polyunsaturated fats, plant-based protein, fiber, vitamins, minerals, and phytochemicals may work together to offer protection against oxidation, inflammation, cancer, and CVD.

Recent findings from the PREDIMED trial suggest that a Mediterranean diet that includes one serving of nuts per day protects against heart attack, stroke, or death from other cardiovascular causes in people at high risk due to type 2 diabetes or metabolic syndrome. PREDIMED data also suggest that eating more than three servings of nuts per week reduces risk of death from all causes, especially if also following a Mediterranean diet. Subjects who frequently consumed both total nuts and walnuts had a lower rate of death from cancer....While the number of nuts per serving varies by type, a typical serving is 1 oz or about 1/4 cup or a small handful (palm of the hand only)....

Almonds are high in monounsaturated fats, which may explain their association with lower LDL cholesterol levels and reduced heart disease risk. The antioxidant function of the vitamin E (37% DV in 1 oz) in almonds along with their magnesium and potassium also may play a role in cardiovascular health. One study found that almonds may reduce LDL as much as statins.

Brazil and cashew nuts: Technically a seed, 1 oz of Brazil nuts contains a whopping 767% DV for selenium. That's over the Tolerable Upper Intake Level of 400 mcg. But eating two Brazil nuts per day has been shown to be an effective way to increase blood levels of this antioxidant mineral healthfully. Cashews are lower in fat than most nuts and contain anacardic acid, which may improve insulin sensitivity and help prevent chronic inflammation.

Pecans contain multiple forms of vitamin E and are especially rich in gamma-tocopherol, which has been shown to inhibit oxidation of LDL cholesterol. Oxidized LDL contributes to inflammation in the arteries and is a risk factor for CVD. Pecans also have the highest polyphenol and flavonoid content of the tree nuts.

Pistachios: Two studies have shown that eating in-shell pistachios enhances feelings of fullness and satisfaction while reducing caloric intake. When eating in-shell pistachios, study subjects consumed about 40% fewer calories compared with pistachio kernels. Pistachios have the second highest polyphenol and flavonoid content of the tree nuts. 

Walnuts are another excellent source of plant-based omega-3 fatty acids. Walnuts also boast the highest antioxidant content of the tree nuts, followed by pecans and cashew nuts. This makes walnuts one of the best nuts for anti-inflammatory benefits. Like pecans, walnuts are unusually rich in the gamma-tocopherol form of vitamin E. ... Walnut consumption among NHANES subjects is positively associated with cognitive function in both younger and older adults. They're a natural source of melatonin, which is critical in the regulation of sleep, circadian (daily) rhythms, and may play a role in walnuts' anticancer benefits.

A cataract is a clouding of the lens in the eye leading to a decrease in vision. It can affect one or both eyes, it is more common with age, and can even lead to blindness. About 20 million people globally are blind due to cataracts. Vitamin supplements have failed to find an effect in numerous studies.

But in this study, eating foods rich in vitamin C and to a smaller degree manganese had the beneficial effect of slowing cataract progression over the course of 9 1/2 years. Manganese is a micronutrient that is necessary in small amounts, but it is rare to be deficient in manganese. However manganese has numerous negative effects if too much is ingested or if there is too much exposure. Bottom line: increased intake of fruit and vegetables (for vitamin C) could help prevent the development or progression of cataracts.  From Medical Xpress:

Increased vitamin C in the diet could help protect against cataracts

Higher dietary intake of vitamin C has been found to have a potentially preventative effect on cataract progression in the first twin study of cataracts to examine to what degree genetic and environmental factors influence their progression with age. Cataract is a common condition in which the lens of the eye becomes cloudy as a result of oxidation over time. Whilst this is a natural part of ageing for many, for others it is more severe and causes blurred vision, glare and dazzle that cannot be corrected by glasses or contact lenses.

The study, led by King's College London and published in the journal Ophthalmology, looked at the progression of cataracts in the eyes of 324 pairs of female twins .... They found that those participants who had a higher intake of vitamin C were associated with a 33 per cent risk reduction of cataract progression and had 'clearer' lenses after the 10 years than those who had consumed less vitamin C as part of their diet.

The study, funded by the Wellcome Trust and Guide Dogs for the Blind, also found that environmental factors (including diet) influenced cataract more than genetic factors, which only explained a third of the change in lens opacity. The fluid in the eye that bathes the lens is high in vitamin C, which helps to stop the lens from oxidising and protects it from becoming cloudy. It is thought that increased intake of vitamin C has a protective effect on cataract progression by increasing the vitamin C available in the eye fluid.

Kate Yonova-Doing, the study's first author said: 'The human body cannot manufacture vitamin C, so we depend on vitamins in the food we eat. We did not find a significantly reduced risk in people who took vitamin tablets, so it seems that a healthy diet is better than supplements.'

A thought-provoking article by Heiman and Greenway was just published in the journal Molecular Metabolism making the case that changes in farming practices over the last 50 years have resulted in decreased agricultural diversity which, in turn, has resulted in decreased dietary diversity, and that the reduction in dietary diversity has changed and decreased the richness of the human gut microbiota (microbes living in the gut). And meanwhile, during the past 50 years, the rates of obesity, type 2 diabetes, and inflammatory bowel diseases sharply increased - and in each of these conditions there is a reduction of the gut microbial diversity. Similar views have also been stated by others in the field of microbiology.

The thinking is that the more diverse the diet, the more diverse the gut microbiome (and healthier), and the more it can adapt to disturbances. Heiman and Greenway state: "Unfortunately, dietary diversity has been lost during the past 50 years because of economic pressures for greater food production to support a growing world population.... Of the 250,000 to 300,000 known edible plant species, humans use only 150 to 200...Today, 75 percent of the world's food is generated from only 12 plants and five animal species."

Also, agricultural practices of using antibiotics as growth promoters for poultry, swine, and cattle further harm the human gut microbiome when the meat is ingested by humans, and pesticide residues on crops ingested by humans may have gut microbiome effects. Even emulsifiers, used in processed foods, reduce microbial richness. Every time a person goes on a certain diet (vegan, Paleo, etc) or makes dietary choices in which some foods are eliminated, it makes it easier for some microbial species, and gives them a competitive advantage over other gut microbes. From Science Daily:

Reduction in dietary diversity impacts richness of human gut microbiota

Changes in farming practices over the last 50 years have resulted in decreased agro-diversity which, in turn, has resulted in decreased dietary diversity. The significant impact of this change in dietary richness on human health is an emerging topic for discussion

Heiman and Greenway describe how the reduction in dietary diversity has changed the richness of human gut microbiota, the community of microorganisms living in the gut. The researchers point out that healthy individuals have diverse gut microbiota and many of the common pathologies of the 21st century, including type 2 diabetes, obesity and inflammatory bowel disease, are associated with reduced microbiotic richness.

Gut microbiota function as an endocrine organ, metabolizing specific nutrients from the diet and producing specific substances that act as metabolic signals in the host. It follows then that highly specialized diets will change the landscape of the gut microbiome over time. In fact, it takes only a few days of changing diet to alter the microbiotic makeup of the human gut. And if the dietary change involves elimination of one or more macronutrients (think Atkins or Paleo or vegan), humans are essentially selecting for some microbiotic species over others.

The importance of microbiota diversity cannot be overstated. They produce an abundance of important molecules for the host and with increased variation comes increased adaptability and an increased range of physiological responses. "The greater the repertoire of signals, the more likely is the ability to maintain homeostasis when dietary intake is perturbed," explain Heiman and Greenway. "Furthermore, because each particular macronutrient has the potential to be metabolized by microbiota into unique metabolic signals, the greater the variety in signals, the greater the variety of responses possible."