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Nothing new here, but good to have it discussed again: eating foods high in potassium and low in sodium (salt) lowers blood pressure. Why should we care? Hypertension (high blood pressure) is a global health issue. The World Health Organization estimates that hypertension is responsible for at least 51 percent of deaths due to stroke and 45 percent of deaths due to heart disease.

Eating the potassium rich foods seems to be key. Some foods high in potassium: bananas, baked potatoes, sweet potatoes, dark leafy greens (e.g., spinach, kale), tomatoes, mushrooms, beans (e.g., white beans, pinto beans), lentils, nuts, broccoli, apricots, milk. In other words, eat an assortment of fruits, vegetables, beans, and nuts to get potassium. And coincidentally these same foods are low in sodium (salt) - a win-win for heath. From Science Daily:

Fruits and vegetables' latest superpower? Lowering blood pressure

Eating potassium-rich foods like sweet potatoes, avocados, spinach, beans, bananas -- and even coffee -- could be key to lowering blood pressure, according to Alicia McDonough, PhD, professor of cell and neurobiology at the Keck School of Medicine of the University of Southern California (USC). "Decreasing sodium intake is a well-established way to lower blood pressure," McDonough says, "but evidence suggests that increasing dietary potassium may have an equally important effect on hypertension."

McDonough explored the link between blood pressure and dietary sodium, potassium and the sodium-potassium ratio in a review article....McDonough's review found several population studies demonstrating that higher dietary potassium (estimated from urinary excretion or dietary recall) was associated with lower blood pressure, regardless of sodium intake. Interventional studies with potassium supplementation also suggested that potassium provides a direct benefit.

McDonough reviewed recent studies in rodent models, from her own lab and others, to illustrate the mechanisms for potassium benefit. These studies indicated that the body does a balancing act that uses sodium to maintain close control of potassium levels in the blood, which is critical to normal heart, nerve and muscle function. "When dietary potassium is high, kidneys excrete more salt and water, which increases potassium excretion," McDonough says. "Eating a high potassium diet is like taking a diuretic." "If you eat a typical Western diet," McDonough says, "your sodium intake is high and your potassium intake is low. This significantly increases your chances of developing high blood pressure." 

But how much dietary potassium should we consume? A 2004 Institute of Medicine report recommends that adults consume at least 4.7 grams of potassium per day to lower blood pressure, blunt the effects of dietary sodium and reduce the risks of kidney stones and bone loss, McDonough says. Eating ¾ cup of black beans, for example, will help you achieve almost 50 percent of your daily potassium goal. [Original study.]

A recent study looking at high dose supplementation of vitamin D found that it did not prevent cardiovascular disease. This study came about because of earlier studies observing that there is a higher incidence of cardiovascular disease in persons with low vitamin D levels (as measured in their blood). But such results from observational studies need rigorous testing in studies where people are randomly assigned to groups, and that are "double-blind" (no one knows who is getting the vitamin D until the end of the study) to eliminate bias. And this is what was done in this study, with the result that monthly high doses of vitamin D3 for 3 years did not prevent cardiovascular disease (including stroke, heart attacks, hypertension, etc) - as seen in that there were no group differences between the vitamin D and placebo groups. Finding no effects are "null findings".

But note that the subjects in the study got monthly high doses, and not daily or weekly vitamin D. It is unknown whether daily dosing would have made a difference in the results. However, the vitamin D levels in the blood soon reached levels (about 51.725 ng/mL) that many view as a desirable "protective" level. So we'll see what other studies find. But these results are definitely disappointing for those wanting an easy "magic bullet" for preventing cardiovascular disease. Bottom line: focus on lifestyle (diet, exercise, not smoking, etc) for heart health. From Science Daily:

Monthly high-dose vitamin D supplementation does not prevent cardiovascular disease

Results of a large randomized trial indicate that monthly high-dose vitamin D supplementation does not prevent cardiovascular disease, according to a study published by JAMA Cardiology. Studies have reported increased incidence of cardiovascular disease (CVD) among individuals with low vitamin D status. To date, randomized clinical trials of vitamin D supplementation have not found an effect, possibly because of using too low a dose of vitamin D. Robert Scragg, M.B.B.S., Ph.D., of the University of Auckland, New Zealand, and colleagues randomly assigned adults (age 50 to 84 years) to receive oral vitamin D3 (n = 2,558; an initial dose of 200,000 IU, followed a month later by monthly doses of 100,000 IU) or placebo (n = 2,552) for a median of 3.3 years.

Of the 5,108 participants included in the primary analysis, the average age was 66 years; 25 percent were vitamin D deficient. Cardiovascular disease occurred in 303 participants (11.8 percent) in the vitamin D group and 293 participants (11.5 percent) in the placebo group. Similar results were seen for participants with vitamin D deficiency at study entry and for other outcomes such as heart attack, angina, heart failure, hypertension, and stroke.

The authors write that the results of this study do not support the use of monthly high-dose vitamin D for the prevention of CVD. "The effects of daily or weekly dosing on CVD risk require further study." [Original study.]

More research supports that being exposed to pets during pregnancy or in the first months of life changes the gut bacteria, and in a way that is thought to be beneficial. The researchers found that infants exposed to pets prenatally or after birth (or both) had higher levels of two microbes that are associated with a lower risk of allergies and obesity. The two microbes are Ruminococcus and Oscillospira, but in case you're wondering - they are not (yet) available in probiotics.

And these differences in gut bacteria occurred no matter how the infants were born or fed (C-section, vaginal, breastfed, formula fed), or whether they received antibiotics at birth or not  - it was the pet exposure that was most important. The evidence is building that if one wants to avoid allergies in children - to have them exposed to furry pets in the first  year of life, and according to this study - perhaps before birth also. From Science Daily:

Pet exposure may reduce allergy and obesity

A new University of Alberta study showed that babies from families with pets -- 70 per cent of which were dogs -- showed higher levels of two types of microbes associated with lower risks of allergic disease and obesity.

"There's definitely a critical window of time when gut immunity and microbes co-develop, and when disruptions to the process result in changes to gut immunity," said Anita Kozyrskyj, a U of A pediatric epidemiologist....The latest findings from Kozyrskyj and her team's work on fecal samples collected from infants registered in the Canadian Healthy Infant Longitudinal Development study build on two decades of research that show children who grow up with dogs have lower rates of asthma

Her team of 12, including study co-author and U of A post-doctoral fellow Hein Min Tun, take the science one step closer to understanding the connection by identifying that exposure to pets in the womb or up to three months after birth increases the abundance of two bacteria, Ruminococcus and Oscillospira, which have been linked with reduced childhood allergies and obesity, respectively.

"The abundance of these two bacteria were increased twofold when there was a pet in the house," said Kozyrskyj, adding that the pet exposure was shown to affect the gut microbiome indirectly -- from dog to mother to unborn baby -- during pregnancy as well as during the first three months of the baby's life. In other words, even if the dog had been given away for adoption just before the woman gave birth, the healthy microbiome exchange could still take place.

The study also showed that the immunity-boosting exchange occurred even in three birth scenarios known for reducing immunity, as shown in Kozyrskyj's previous work: C-section versus vaginal delivery, antibiotics during birth and lack of breastfeeding. What's more, Kozyrskyj's study suggested that the presence of pets in the house reduced the likelihood of the transmission of vaginal GBS (group B Strep) during birth, which causes pneumonia in newborns and is prevented by giving mothers antibiotics during delivery. [Original study.]

 Nice research that basically says: food is medicine. In other words, eat lots of whole grains and legumes (beans) for gut health - to feed the beneficial microbes in your gut and prevent (hopefully) colon cancer. While the clinical trial studied colorectal cancer survivors and the effects of 4 weeks of adding rice bran or navy beans or placebo (nothing extra) daily to their diet - the positive effects of adding the extra dietary fiber included increased microbiome richness and diversity in the rice bran group (which is good).

And when researchers treated colorectal cancer cells with stool extracts from these groups, they saw reduced cell growth from the groups that had increased rice bran and navy bean consumption. This was an important finding and stresses that adding fiber to the diet is beneficial to gut health, and perhaps may prevent colorectal cancer.

Other studies have also found a diet with lots of legumes (beans), whole grains, vegetables, fruits, nuts, and seeds to be beneficial for gut microbes and gut health. A classic study (from 2015) found dramatic changes in the colon (specifically in the colonic mucosa) from dietary changes in as little as 2 weeks. They compared the typical low-fat, high fiber diet of South Africa with an “American” high-fat, low-fiber diet, and found that after two weeks on the high fiber African diet, there was significantly less inflammation in the colon and reduced biomarkers of cancer risk. On the other hand, measurements indicating cancer risk dramatically increased after two weeks on the western diet. That study found that a major reason for the changes in cancer risk was the way in which the bacteria in the gut (the microbiome) were altered in adapting to the new diet. The researchers suggested trying for at least 50 grams of fiber per day for gut health benefits.

From Medical Xpress: Phase II trial: Rice bran adds microbiome diversity, slows growth of colon cancer cells

Today at the American Association for Cancer Research (AACR) Annual Meeting 2017, University of Colorado Cancer Center researchers at Colorado State University present results of a phase II clinical trial of 29 people exploring the effects of adding rice bran or navy beans to the diets of colorectal cancer survivors. After the 4-week randomized-controlled trial during which people added rice bran, navy bean powder or neither, both the rice bran and navy bean groups showed increased dietary fiber, iron, zinc, thiamin, niacin, vitamin B6, folate, and alpha-tocopherol. The rice bran group also showed increased microbiome richness and diversity. When researchers treated colorectal cancer cells with stool extracts from these groups, they saw reduced cell growth from the groups that had increased rice bran and navy bean consumption.

Previous work shows the ability of these diets to decrease colorectal cancer risk in animal models. The current trial confirms that people can eat enough bean- and rice bran-enhanced foods to promote gut health at levels shown to prevent colorectal cancer in animals. Guidelines from the American Institute for Cancer Research recommend reducing the risk of cancer by eating more vegetables, fruits, whole grains and legumes, such as beans. Ryan has established from these studies that eating a half-cup of beans and 30 grams of rice bran per day is enough to see changes in small molecules that can confer protection against colorectal cancer.

"The simple message is, 'Food is medicine,' and we are looking at how to simplify that and make it apply to our everyday lives," says study co-author Regina Brown, MD, assistant professor at the CU School of Medicine and oncologist for CUHealth...."The evidence is there in animals and we can now study this in people. The question is, what are we doing to achieve adequate levels of intake of these foods?" Ryan said. "It's not enough to say 'I eat them once in a while.' That's not going to work, particularly if you are at higher risk. You have to meet a dose, just like you need a dose of a certain drug, you need to reach intake levels and consume increased amounts of these foods, and that's where people, including me, are challenged. Not everyone wants to open up a can of beans and eat them every day."

Image result for stethoscope A new Mayo Clinic study reinforces that YES - a person  should get a second opinion when dealing with a complex medical condition. The study compared the referring diagnosis to the final diagnosis of 286 patients referred to the Mayo Clinic by physician assistants, nurse practitioners, and physicians. The researchers found that in only 12 percent of the cases was the diagnosis confirmed. In 21 percent of the cases, the diagnosis was completely changed, while 66 percent of patients received a refined or redefined diagnosis. There were no significant differences between the referring diagnoses made by physician assistants, nurse practitioners, and physicians.

But one concern I have with the study is - how do we know that the Mayo Clinic diagnosis was the correct one, especially in the 21% of cases they gave a completely different diagnosis (what they called "misdiagnosis")? Hmm..? Bottom line: Yes, a second opinion adds to the medical costs, but it may be helpful. From Science Daily:

The value of second opinions demonstrated in study

Many patients come to Mayo Clinic for a second opinion or diagnosis confirmation before treatment for a complex condition. In a new study, Mayo Clinic reports that as many as 88 percent of those patients go home with a new or refined diagnosis -- changing their care plan and potentially their lives. Conversely, only 12 percent receive confirmation that the original diagnosis was complete and correct.

Often, because of the unusual nature of the symptoms or complexity of the condition, the physician will recommend a second opinion. Other times, the patient will ask for one.....To determine the extent of diagnostic error, the researchers examined the records of 286 patients referred from primary care providers to Mayo Clinic's General Internal Medicine Division in Rochester over a two-year period (Jan. 1, 2009, to Dec. 31, 2010). This group of referrals was previously studied for a related topic. It consisted of all patients referred by nurse practitioners and physician assistants, along with an equal number of randomly selected physician referrals.

The team compared the referring diagnosis to the final diagnosis to determine the level of consistency between the two and, thus, the level of diagnostic error. In only 12 percent of the cases was the diagnosis confirmed. In 21 percent of the cases, the diagnosis was completely changed; and 66 percent of patients received a refined or redefined diagnosis. There were no significant differences between provider types.

A possible problem with running marathons is short term kidney injury in the two days right after the race. A study of 22 runners in the 2015 Hartford (Connecticut) Marathon found that most of the runners temporarily developed acute kidney injury (AKI) directly after the race. The study main author Chirag R. Parikh, MD, PhD said: "The kidney responds to the physical stress of marathon running as if it's injured, in a way that's similar to what happens in hospitalized patients when the kidney is affected by medical and surgical complications".

The runners studied fully recovered from the kidney injury 2 days after the event, but the study raises questions about the long-term effects for regular marathon runners, especially in warmer climates. Also, how about the effects of repeated marathons? The researchers say they can only speculate that marathoners adapt to the kidney injury, because they recover within 2 days. But they also pointed out that research has shown there are also changes in heart function associated with marathon running. Something else to keep in mind when considering training for marathons. From Science Daily:

Marathon running may cause short-term kidney injury

According to a new Yale-led study, the physical stress of running a marathon can cause short-term kidney injury. Although kidneys of the examined runners fully recovered within two days post-marathon, the study raises questions concerning potential long-term impacts of this strenuous activity at a time when marathons are increasing in popularity. More than a half million people participated in marathons in the United States in 2015.

While past research has shown that engaging in unusually vigorous activities -- such as mine work, harvesting sugarcane, and military training -- in warm climates can damage the kidneys, little is known about the effects of marathon running on kidney health. A team of researchers led by Professor of Medicine Chirag Parikh, M.D. studied a small group of participants in the 2015 Hartford Marathon. The team collected blood and urine samples before and after the 26.2-mile event. They analyzed a variety of markers of kidney injury, including serum creatinine levels, kidney cells on microscopy, and proteins in urine.

The researchers found that 82% of the runners that were studied showed Stage 1 Acute Kidney Injury (AKI) soon after the race. AKI is a condition in which the kidneys fail to filter waste from the blood. "The kidney responds to the physical stress of marathon running as if it's injured, in a way that's similar to what happens in hospitalized patients when the kidney is affected by medical and surgical complications," said Parikh. The researchers stated that potential causes of the marathon-related kidney damage could be the sustained rise in core body temperature, dehydration, or decreased blood flow to the kidneys that occur during a marathon. [Original study.]

Does vitamin D prevent cancer? There has been much debate over whether increasing levels of vitamin D (as measured in a person's blood) results in a lower incidence of cancer. Studies find a number of health problems linked to low levels of vitamin D (here, here, here), while studies looking at vitamin D and cancer have been "inconsistent" in their results. Some say yes - vitamin D is protective, while some say there is no effect from vitamin D supplements. Now a 4 year study (yes, yes - it's a very short length of time in which to study the onset of cancer) found no difference in the rate of cancer among two groups of postmenopausal women who received either: 2,000 IU per day of vitamin D3 and 1,500 mg per day of calcium OR an identical looking placebo. They looked for any kind of cancer occurring.

The Creighton University researchers found a difference among the women after 4 years, with the vitamin D plus calcium supplement group having fewer cancers (and a lower percentage of cancer) as compared to the placebo group, but...it did not reach statistical significance. So you could say it was due to chance. But when the researchers looked at the number of cancers from year 2 to 4, then the difference was statistically significant - that vitamin D was protective. The researchers wonder if the cancers diagnosed in year 1 were already developing before the study started. Note: The 2,000 IU per day vitamin D3 supplements in this study are considered high doses - "high dose supplementation".

The researchers point out that the women who were given vitamin D3 and calcium supplements had a 30% lower risk of cancer, even though this difference in cancer incidence rates between the 2 groups did not quite reach statistical significance. But both groups started with a fairly high vitamin D level -  an average 25-hydroxyvitamin D (25[OH]D) levels of 32.8 ng/m (which is above the average US population level). And in the supplement group it was raised to 43.9 ng/mL. Note that some researchers view vitamin D levels of 33 ng/mL  (the baseline level in both groups) as already protective against cancer.

Also, even during the study the placebo group was allowed to take their own vitamin D and calcium supplements as long as it wasn't more than the recommended amounts (800 IU per day for vitamin D and 1500 mg per day for calcium) - which makes those individuals actually a low vitamin D supplementation group rather than no supplementation, which might hide any treatment effects and so make the results for the 2 groups look similar. What is needed is a much longer follow-up, larger groups of women, and both high and low dose vitamin D supplement groups. Some studies suggest that whether a low or high dose taken has an effect on cancer incidence.

I still think this study period was way too short - to me, 5 or more years would have been more convincing, and the groups too small. Also, it was unfortunate that they were also given calcium supplements or that there wasn't a just vitamin D group. Combining vitamin D with calcium supplements just muddies the results (in my opinion), and also because calcium supplements are linked to health problems such as cardiovascular disease. So in this study can't tell what the separate effects of calcium and vitamin D are. (Note that calcium rich foods, however, are beneficial to health.)

But a big positive of the study was that the women were randomly assigned to either the vitamin D plus calcium group or the placebo group, and no one - not the women or their doctors knew who got what until the end of the study (to eliminate bias it was "double-blind"). Note The supplements used were vitamin D3 and not D2. Vitamin D can also be easily obtained by exposure to sunlight in the summer months.

Excerpts from Creighton University release about the study in Science Daily: Does Vitamin D decrease risk of cancer?

The study, funded by the National Institutes of Health, is a randomized clinical trial of the effects of vitamin D supplementation on all types of cancer combined. The four-year study included 2,303 healthy postmenopausal women 55 years and older from 31 counties in Nebraska. Participants were randomly assigned to take either 2000 international units (IU) of vitamin D3 and 1500 mg. of calcium or identical placebos daily for 4 years. The vitamin D3 dose was about three times the US government's Recommended Dietary Allowance (RDA) of 600 IU for adults through age 70, and 800 IU for those 71 and older. Women who were given vitamin D3 and calcium supplements had 30% lower risk of cancer. This difference in cancer incidence rates between groups did not quite reach statistical significance. However, in further analyses, blood levels of vitamin D, specifically 25-hydroxyvitamin D (25(OH)D), were significantly lower in women who developed cancer during the study than in those who remained healthy.

Is this really a surprise to anyone at this point? According to a recent study: Almost half of all deaths in the United States in 2012 that were caused by cardiometabolic diseases such as heart disease, stroke and type 2 diabetes, have been linked to "suboptimal diets" - that is, to eating poorly and so not getting enough of certain foods and nutrients, and too much of other foods. Deaths due to heart disease, stroke, or type 2 diabete were linked to: high sodium (salt) intake, not eating enough nuts and seeds, a high intake of processed meats, and low intake of seafood omega-3 fats.

The study looked at consumption of 10 foods or nutrients that are associated with cardiometabolic diseases: fruits, vegetables, nuts/seeds, whole grains, unprocessed red meats, processed meats, sugar-sweetened beverages (SSBs), polyunsaturated fats, seafood omega-3 fats, and sodium. The researchers incorporated data from National Health and Nutrition Examination Surveys, from studies and clinical trials, and from the National Center for Health Statistics. So how should one eat for heath? Lots of fruits and vegetables, legumes (beans), nuts, seeds, whole grains, fish, and less processed food and fast food. (A plus of this is that it also feeds your beneficial gut microbes.) Read ingredient lists and try to avoid whatever foods have ingredients that you ordinarily wouldn't cook with or don't understand what they are (for example, colors, additives, titanium dioxide, artificial or natural flavors, etc.). From Science Daily:

High number of deaths from heart disease, stroke and diabetes linked to diet

Nearly half of all deaths in the United States in 2012 that were caused by cardiometabolic diseases, including heart disease, stroke and type 2 diabetes, have been linked to substandard eating habits, according to a study published in the March 7 issue of JAMA and funded by the National Heart, Lung, and Blood Institute (NHLBI), part of the National Institutes of Health. Of the 702,308 adult deaths due to cardiometabolic diseases, 318,656, or about 45 percent, were associated with inadequate consumption of certain foods and nutrients widely considered vital for healthy living, and overconsumption of other foods that are not.

The list includes foods and nutrients long-associated with influencing cardiometabolic health. The highest percentage of deaths was linked to excess consumption of sodium. Processed meats, sugar-sweetened beverages and unprocessed red meats were also consumed in excess. Americans did not consume enough of some foods that have healthful effects such as fruits, vegetables, nuts and seeds, whole grains, polyunsaturated fats and seafood omega-3 fats.

The study also shows that the proportion of deaths associated with diet varied across population groups. For instance, death rates were higher among men when compared to women; among blacks and Hispanics compared to whites; and among those with lower education levels, compared with their higher-educated counterparts. The authors concluded that "these results should help identify priorities, guide public health planning, and inform strategies to alter dietary habits and improve health." The study findings were based on death certificate data collected by the National Center for Health Statistics, part of the Centers for Disease Control and Prevention.

Since my last post on the most commonly used pesticide in the world - glyphosate - there have been a number of important developments. Glyphosate is the active ingredient in the weed-killer or herbicide Roundup, which is manufactured by the chemical giant Monsanto. There have been more questions raised about the safety of glyphosate, and also what went on behind the scenes recently between Monsanto and some officials at the EPA, especially EPA deputy division director Jess Rowland.

Was there a downplaying of the pesticide's health effects or squashing of researchers and studies that raised health concerns? (Remember that the International Agency for Research on Cancer, a branch of the World Health Organization, found glyphosate to be a "probable carcinogen" in 2015, but the manufacturer Monsanto has fought long and hard against that designation) Was there corruption? Or ...?

A big problem is that the EPA relies on industry-funded studies to determine if something is safe or not - which is like the fox guarding the chicken house. Also, were the so-called "independent" research articles actually ghost-written by industry (Monsanto), which is what some documents are suggesting? And why was a government review of the pesticide squashed? Tsk.... tsk.... Another problem is that the EPA can choose which studies to include when making a decision - and they can choose to disregard independent peer-reviewed research (the better research) and rely on industry studies that are not peer-reviewed (definitely bias in these studies). And yes, this happened here. For example, the EPA has ignored more than 1500 published (and peer reviewed) studies on glyphosate from the last decade and instead relied largely on less than 300 unpublished, non-peer-reviewed studies. Another tsk...tsk....

Now a published paper by noted researchers (see below) makes the case that the debate over glyphosate remains unsettled and requires further review. The researchers recommend such things as better testing of glyphosate levels and its metabolites in the human body. They pointed out that some studies with rodents found that glyphosate is a carcinogen (can "induce cancers"), and other studies find glyphosate is associated with negative health effects in humans, such as chronic kidney disease and some cancers. Some research suggests that glyphosate is an endocrine disruptor. Also, chemical mixtures can be more toxic than individual chemicals - this is a concern with the chemicals in Roundup. Studies are needed examining people exposed through their occupations (e.g., pesticide applicators), and also "vulnerable populations (e.g., pregnant women, babies, children). The researchers added that current safety standards are outdated and may fail to protect public health and the environment.

I would like to add that this is why glyphosate residues need to be studied in food - we are eating the stuff unless we only eat organic food. Due to the practices of "preharvest application" of glyphosate (Roundup) and the increasing use of genetically modified crops (such as Roundup Ready crops) that allow the herbicide to be applied without killing the crop (but which means the pesticide is in the crop), the use of glyphosate is increasing rapidly. And then there is the use on school grounds, in suburban yards, and properties. Yikes! This is not a political issue - this is a health issue, and of having the right-to-know what is in our food, our bodies, and our environment (you don't think it just stays on the fields where it is used, do you?)

Excerpts from the NY Times article: Monsanto Weed Killer Roundup Faces New Doubts on Safety in Unsealed Documents

The reputation of Roundup, whose active ingredient is the world’s most widely used weed killer, took a hit on Tuesday when a federal court unsealed documents raising questions about its safety and the research practices of its manufacturer, the chemical giant Monsanto.... A case in federal court in San Francisco has challenged that conclusion, building on the findings of an international panel that claimed Roundup’s main ingredient might cause cancer.

The court documents included Monsanto’s internal emails and email traffic between the company and federal regulators. The records suggested that Monsanto had ghostwritten research that was later attributed to academics and indicated that a senior official at the Environmental Protection Agency had worked to quash a review of Roundup’s main ingredient, glyphosate, that was to have been conducted by the United States Department of Health and Human Services. The documents also revealed that there was some disagreement within the E.P.A. over its own safety assessment.

Excerpts from an article about the BMJ paper (see below) at Science Daily: Weedkiller chemical (glyphosate) safety standards need urgent review

But most of the science used to support the safety standards applied in the US was carried out more than 30 years ago, and relatively little of it was subject to peer review, they point out. More than 1500 studies have been published on the chemical over the past decade alone. "It is incongruous that safety assessments of the most widely used herbicide on the planet rely largely on fewer than 300 unpublished, non-peer reviewed studies while excluding the vast modern literature on glyphosate effects," say the experts. And despite the rapid increase in use there is no systematic monitoring system for tracking levels in human tissue, and few studies have looked at potential harms to human health.

But recent animal studies have suggested that glyphosate at doses lower than those used to assess risk, may be linked to heightened risks of liver, kidney, eye and cardiovascular system damage. And weed-killers, which combine glyphosate with other 'so-called inert ingredients,' may be even more potent. But these mixtures are regarded as commercially sensitive by the manufacturers and are therefore not available for public scrutiny, say the experts.

Excerpt from the BMJ Journal of Epidiomology and Community Health: Is it time to reassess current safety standards for glyphosate-based herbicides?

Use of glyphosate-based herbicides (GBHs) increased ∼100-fold from 1974 to 2014. Additional increases are expected due to widespread emergence of glyphosate-resistant weeds, increased application of GBHs, and preharvest uses of GBHs as desiccants. Current safety assessments rely heavily on studies conducted over 30 years ago. We have considered information on GBH use, exposures, mechanisms of action, toxicity and epidemiology. Human exposures to glyphosate are rising, and a number of in vitro and in vivo studies challenge the basis for the current safety assessment of glyphosate and GBHs. We conclude that current safety standards for GBHs are outdated and may fail to protect public health or the environment.

Why is the US Department of Agriculture (USDA) dropping plans to test for glyphosate residues in food? It was supposed to start soon (April 1, 2017), in coordination with the Environmental Protection Agency (EPA) and the Food and Drug Administration (FDA), but now all plans to test have been dropped. Why is this worrisome? The issue is that glyphosate is currently the most widely used pesticide in the world. It is a herbicide that is the active ingredient in the herbicide commonly known as Roundup. Global use was 1.65 billion pounds in 2014 , while overall use in the US was 276.4 million pounds in 2014. Glyphosate is a probable human carcinogen and linked to various health effects, and research shows that glyphosate residues are commonly found in foods.

Even though whether glyphosate is a carcinogen is hotly debated by some groups (with Monsanto fiercely fighting against such a label), it shouldn't matter in the decision of whether to test for glyphosate residues in foods. What is going on with our food, and whether and how much glyphosate residues are in food should be monitored. Government agencies (such as USDA) test for other pesticide residues, and they should do the same for glyphosate, especially because it is so widely used.

The FDA did test for a short while last year (2016) and then stopped in the fall, and yes, they found residues in the foods they studied. Government and private testing has already found glyphosate residues in breast milk, soybeans, corn, honey, cereal, wheat flour, oatmeal, soy sauce, beer, and infant formula. It is currently unknown what the glyphosate residues in food that we eat means for human health. Several studies have linked glyphosate to human health ailments, including non-Hodgkin lymphoma and kidney and liver problems. Of special concern is that because glyphosate is so pervasive in the environment, even trace amounts might be harmful due to chronic exposure. Glyphosate is patented by its manufacturer (Monsanto) for its antibacterial properties - thus it can be viewed as an antibiotic. What is it doing to our gut microbes when ingested? Some people (including researchers) are even suggesting that much of "gluten sensitivity" or "gluten intolerance" that people complain of, may actually be sensitivity to glyphosate residues in food. There are many unanswered questions.

So....is this a case of burying the head in the sand? That there are no problems if no one looks for them? The EPA has long known that glyphosate residues are occurring in food because in 2013 the EPA raised "tolerance limits" for human exposure to glyphosate for certain foods, stating with "reasonable certainty that no harm will result" from human exposure to the chemical. This increase in tolerance levels came about from a request from Monsanto (the manufacturer of the glyphosate herbicide Roundup), and even though numerous groups protested the increase, the EPA went along with Monsanto's request. Some tolerances doubled. Pesticide residues are an important issue - because we don't know what chronic exposure to mixtures of low levels of pesticides (which includes glyphosate) in foods does to us. To babies and children, to pregnant women, to the elderly, to all of us.

But remember.... there are very strong industry pressures on the EPA and USDA, with some government officials also having ties to the industry, and so perhaps it's a case of keeping the head firmly in the sand for all sorts of pesticide issues. Maybe the motto is: see no evil...hear no evil....There have been some lawsuits from people claiming harm from the pesticide, as well as push back from scientists and environmental groups. Some influential scientists and physicians came out with a Statement of Concern in 2016 regarding their serious concerns with glyphosate.

The reason that glyphosate tolerance limits needed to be increased in the USA is because Roundup Ready crops are now so extensively planted, and this has resulted in skyrocketing use of glyphosate in the last 20 years. Roundup Ready crops are genetically modified to tolerate repeated glyphosate spraying (against weeds)  during the growing season. However, the crops take up and accumulate  glyphosate, and so glyphosate residues are increasing in crops. Another reason for increased residue of glyphosate in crops is the current practice of applying an herbicide such as Roundup right at the time of harvest to non-GMO crops such as wheat, so that the crop dies at once and dries out (pre-harvest crop dessication), and which is called a "preharvest application" by Monsanto. Glyphosate is now off-patent so many other companies are also using glyphosate in their products throughout the world.

How to lower your daily intake of glyphosate? Eat organic foods as much as possible, including wheat, corn, oats, soybeans. Glyphosate is not allowed to be used in organic food production. The following excerpts are from an article by journalist Carey Gillam, and it is well worth reading the entire article. From The Huffington Post:

USDA Drops Plan to Test for Monsanto Weed Killer in Food

The U.S. Department of Agriculture has quietly dropped a plan to start testing food for residues of glyphosate, the world’s most widely used weed killer and the key ingredient in Monsanto Co.’s branded Roundup herbicides. The agency spent the last year coordinating with the Environmental Protection Agency (EPA) and the Food and Drug Administration (FDA) in preparation to start testing samples of corn syrup for glyphosate residues on April 1, according to internal agency documents obtained through Freedom of Information Act requests. Documents show that at least since January 2016 into January of this year, the glyphosate testing plan was moving forward. But when asked about the plan this week, a USDA spokesman said no glyphosate residue testing would be done at all by USDA this year.

The USDA’s plan called for the collection and testing of 315 samples of corn syrup from around the United States from April through August, according to the documents. Researchers were also supposed to test for the AMPA metabolite, the documents state. AMPA (aminomethylphosphonic acid) is created as glyphosate breaks down. Measuring residues that include those from AMPA is important because AMPA is not a benign byproduct but carries its own set of safety concerns, scientists believe.

The USDA does not routinely test for glyphosate as it does for other pesticides used in food production. But that stance has made the USDA the subject of criticism as controversy over glyphosate safety has mounted in recent years. The discussions of testing this year come as U.S. and European regulators are wrestling with cancer concerns about the chemical, and as Monsanto, which has made billions of dollars from its glyphosate-based herbicides, is being sued by hundreds of people who claim exposures to Roundup caused them or their loved ones to suffer from non-Hodgkin lymphoma. Internal Monsanto documents obtained by plaintiffs’ attorneys in those cases indicate that Monsanto may have manipulated research regulators relied on to garner favorable safety assessments, and last week, Congressman Ted Lieu called for a probe by the Department of Justice into Monsanto’s actions.

Along with the USDA, the Food and Drug Administration also annually tests thousands of food samples for pesticide residues. Both agencies have done so for decades as a means to ensure that traces of weed killers, insecticides, fungicides and other chemicals used in farming do not persist at unsafe levels in food products commonly eaten by American families. If they find residues above the “maximum residue level” (MRL) allowed for that pesticide and that food, the agencies are supposed to inform the EPA, and actions can be taken against the supplier. The EPA is the regulator charged with establishing MRLs, also called “tolerances,” for different types of pesticides in foods, and the agency coordinates with USDA and FDA on the pesticide testing programs.

But despite the fact that glyphosate use has surged in the last 20 years alongside the marketing of glyphosate-tolerant crops, both USDA and FDA have declined to test for glyphosate residues aside from one time in 2011 when the USDA tested 300 soybean samples for glyphosate and AMPA residues. At that time the agency found 271 samples contained glyphosate, but said the levels were under the MRL - low enough not to be worrisome. The Government Accountability Office took both agencies to task in 2014 for the failure to test regularly for glyphosate.

The USDA’s most recent published report on pesticide residues in food found that for 2015 testing, only 15 percent of the 10,187 samples tested were free from any detectable pesticide residues. That’s a marked difference from 2014, when the USDA found that over 41 percent of samples were “clean” or showed no detectable pesticide residues. But the agency said the important point was that most of the samples, over 99 percent, had residues below the EPA’s established tolerances and are at levels that “do not pose risk to consumers’ health and are safe.” Many scientists take issue with using MRLs as a standard associated with safety, arguing they are based on pesticide industry data and rely on flawed analyses. Much more research is needed to understand the impact on human health of chronic dietary exposures to pesticides, many say.