The research finding of so many baby foods with elevated arsenic levels (above the legal limit) in the European Union made me wonder about arsenic standards in baby cereals in the US. It turns out that the US has "parallel" standards to the European Union. The EU has "maximum 0.1 milligrams of arsenic per kilogram of rice" (this standard has been in place since January 2016), and in  2016 the US the FDA proposed a "maximum allowed standard of 100 ppb (parts per billion)" in infant rice cereal.

Why is there so much arsenic in baby cereal? It's in the rice - rice plants absorb arsenic from the soil (it may be naturally occurring in the soil or in the soil because of arsenic pesticides that were used for years). And why should we be concerned about arsenic in food? The health effects of regularly consuming infant rice cereal — and other rice-based products —containing traces of arsenic are currently unclear. But...the researchers stated that early-life exposure to arsenic, even at low concentrations, is of particular concern because infants and young children are especially vulnerable to the adverse health effects of arsenic. Arsenic is a carcinogen (causes cancer), and can have "neurological, cardiovascular, respiratory and metabolic" effects.

A Harvard Health Publication (Harvard Medical School) publication in 2016 stated: "In high doses it is lethal, but even small amounts can damage the brain, nerves, blood vessels, or skin — and increase the risk of birth defects and cancer." The FDA found that inorganic arsenic exposure in infants and pregnant women can result in a child’s decreased performance on certain developmental tests that measure learning, based on epidemiological evidence including dietary exposures.

So what should parents do? The American Academy of Pediatricians (AAP) encourages that babies and toddlers eat a variety of foods, and that this will decrease a child's exposure to arsenic from rice. They also encourage other options as first foods (rather than just rice cereal), such as oat, barley, and multigrain cereals - all of which have lower arsenic levels than rice cereal. From Science Daily:

New research shows illegal levels of arsenic found in baby foods

In January 2016, the EU imposed a maximum limit of inorganic arsenic on manufacturers in a bid to mitigate associated health risks. Researchers at the Institute for Global Food Security at Queen's have found that little has changed since this law was passed and that 50 per cent of baby rice food products still contain an illegal level of inorganic arsenic. Professor Meharg, lead author of the study and Professor of Plant and Soil Sciences at Queen's, said: "....Babies are particularly vulnerable to the damaging effects of arsenic that can prevent the healthy development of a baby's growth, IQ and immune system to name but a few."

Rice has, typically, ten times more inorganic arsenic than other foods and chronic exposure can cause a range of health problems including developmental problems, heart disease, diabetes and nervous system damage. As babies are rapidly growing they are at a sensitive stage of development and are known to be more susceptible to the damaging effects of arsenic, which can inhibit their development and cause long-term health problems. Babies and young children under the age of five also eat around three times more food on a body weight basis than adults, which means that, relatively, they have three times greater exposures to inorganic arsenic from the same food item.

The research findings, published in the PLOS ONE journal today, compared the level of arsenic in urine samples among infants who were breast-fed or formula-fed before and after weaning. A higher concentration of arsenic was found in formula-fed infants, particularly among those who were fed non-dairy formulas which includes rice-fortified formulas favoured for infants with dietary requirements such as wheat or dairy intolerance. The weaning process further increased infants' exposure to arsenic, with babies five times more exposed to arsenic after the weaning process, highlighting the clear link between rice-based baby products and exposure to arsenic.

In this new study, researchers at Queen's also compared baby food products containing rice before and after the law was passed and discovered that higher levels of arsenic were in fact found in the products since the new regulations were implemented. Nearly 75 per cent of the rice-based products specifically marketed for infants and young children contained more than the standard level of arsenic stipulated by the EU law.[Original study.]

A 2016 study done in New Hampshire also showed that babies eating rice cereals and other rice-based snacks had higher amounts of arsenic in their urine compared to infants who did not eat rice foods. From JAMA Pediatrics: Association of Rice and Rice-Product Consumption With Arsenic Exposure Early in Life

 Once again a study looked at biofilms in sinuses - but this time in the sinuses of healthy people and not those with sinusitis. Various different species of bacteria and small size "microcolonies" or biofilms were found in the healthy maxillary sinuses of all 30 people - so yes, it appears that the presence of biofilms in the sinuses is normal in healthy people. And yes, the presence of bacteria (even some low levels of species which are typically associated with sinusitis) are normally found in the sinuses of healthy people.  (Earlier research also found this last finding.)

The researchers state that it is normal for people to have "small size bacterial microcolonies" (of different kinds of bacteria) in the sinuses. The researchers theorized that the biofilms are probably "in equilibrium" under the influence of  "inhibiting defensive factors of the body", but they can become a source of infection if there are favorable conditions (such as illness). In other words, the researchers said that these biofilms are more like "bacteria films" in that they contain bacteria, but they live in small colonies that don't cause an inflammatory response with sinusitis symptoms.

One negative of this study was that advanced genetic sequencing was not done on the samples. Instead all samples taken from the people were cultured, which we now know misses a lot of bacterial and other microbial species (fungi, viruses). They looked at the microcolonies (biofilms) with scanning microscopes. Thus, while they found an assortment of bacteria on the sinuses of each person - they only found a total of 41 bacterial species among 30 persons. This is in contrast to studies using modern genetic sequencing that found hundreds of microbial species in healthy sinus microbiomes (microbial communities).

The other issue is that it is not clear to me if there were biofilms or  microcolonies that contained "beneficial" species in any of the samples. Other research suggests that biofilms of beneficial bacteria are also found in humans, and that this is one way beneficial bacteria that normally can't survive with exposure to oxygen can survive oxygen (the slime coating on the colony protects the bacteria within).

Other studies also stress that in healthy people there is "homeostasis" or "equilibrium" among all the microbes living in the sinuses, - a microbial community (which includes biofilms), and which helps maintain sinus health. See post with discussion of Mackenzie et al 2017 study: "A stable network of microbial interactions, established through processes such as niche competition, nutrient cycling, immune evasion, and biofilm formation help maintain homeostasis during health." But, as has been usual in recent sinus research, the current study also stated that much is unknown, that there are theories which are not yet proven one way or another, and more research needs to be done. Of course.... From  PLoS ONE:

The presence of bacterial microcolonies on the maxillary sinus ciliary epithelium in healthy young individuals

The aim of this cross-sectional in vitro study was to evaluate the mucosal surfaces of healthy maxillary sinuses, explore different forms of bacterial microorganism colonies present on the mucous membrane, and determine a mucosal surface area they occupy. Samples of the maxillary sinus mucosa were collected from 30 healthy patients (M = 11; F = 19). The material was obtained during the Le Fort I osteotomy performed during corrective jaw surgery. The morphological and morphometric analysis of sinus mucosa and bacterial film that was grown on it was performed using scanning electron microscopy (SEM) as well as imaging software.

Scanning electron microscopy analysis showed the presence of different bacterium and bacteria-like structures in all the analyzed samples. In most cases, the bacterial film was mostly composed of diplococci-like and streptococci-like structures on the mucosa of the paranasal sinus. In any case, the mucous layer did not cover the whole lining of the evaluated sample. Each colony consists of more than 20 single bacterial cells, which has grown in aggregates.

Under the conditions of normal homeostasis of the body, the maxillary sinuses present diverse bacterial colonization. The bacteria are dispersed or concentrated in single microcolonies of the biofilm on the border of the mucous covering the ciliary epithelium. There is no uniform layer of the biofilm covering the mucosa of the maxillary sinuses. Because the biofilm is detected on healthy individuals sinus mucosa, the clinical question if it may become pathogenic is unclear and require an explanation.

It should also be noted that pathogenic organisms, such as Pseudomonas aeruginosa, Haemophilus influenzae, Streptococcus pneumoniae, or Staphylococcus aureus can be found in patients without active symptoms of the disease. Usually, colonization is defined as the presence of bacteria on the mucous membrane, and the lack of the inflammatory response distinguishes it from an infection.

However, the bacteria film in contrast to typical biofilm might be defined by the presence of bacteria, that growth in colonies without inducing the inflammatory response. Thus, the aim of the study was to evaluate the mucosal surfaces of the healthy maxillary sinuses (without any history of recent acute sinus inflammations or chronic inflammation in the past), to identify different forms of bacterial microorganisms which could, under certain conditions, become opportunistic or pathogenic and determine a mucosal surface of the area they occupy.

Scanning electron microscope investigations revealed the presence of bacterial film on the surface of maxillary sinus mucosa in 30 patients. Moreover, microbiological examinations of specimens taken from study participants revealed the presence of various types of aerobic and anaerobic bacteria in 28 cases (93.34%) out of 30 studied samples. All samples had mixed flora. In total, 41 different microorganisms were isolated. The most frequently found microorganism was Streptococcus spp. in over 90% of all samples, while Propionibacterium acnes were present in 29,2% of samples, and Staphylococcus spp. was present in 17% of the samples.

Scanning electron microscopy analysis showed that the mucous layer has a thickness of 200 nm (± 40), which is covered up to 5% of the surface of each sample. The analysis showed the presence of bacteria-like microcolony structures in all analyzed samples.....Each colony consisted of more than 20 single bacterial cells, that had grown in aggregates. These clearly indicate the existence of a bacterial-like microcolony on maxillary sinus mucosa.

thumbnailScanning electron microscopy images of biofilms seen on the mucosal surface of the healthy paranasal sinus mucosa. See spherical structures related to Haemophilus influenzae (Fig B and D). Credit: Morawska-Kochman et al 

Image result for stethoscope Dr. John Mandrola (physician and medical writer) has once again written thought provoking posts about medicine and the need for people to question tests, procedures, screening, and to look at the harms and benefits. Because YES - all of the above have harms and benefits, even something as "minor" as taking an antibiotic for a week or two (for example, effects on the gut microbes).

Excerpts from his April 20 post at drjohnm.orgTrust and Medical Science

I first addressed the lack of skepticism among my colleagues. I argue that doctors have become a rapturous audience for medical news. We too easily accept flawed evidence. Our embrace of a flawed dissolving coronary stent and a left atrial appendage closure device serve as good examples of misplaced optimism.

In the second section of the essay, I explore the problem with overselling science. Here’s an except: Science does not do itself. Humans—bent on having a successful academic career—do science. This means positive results can become the goal rather than the pursuit of scientific truth.

I spent three paragraphs on evangelism over screening healthy people. It crushes the public trust to say “screening saves lives” when the evidence doesn’t support the claim. This is not a typo. I cite numerous studies that show common screening tests, mammography, PSA tests, colonoscopy, when put to the test of a randomized controlled trial, do not lower overall death rates.

The obfuscation comes when screening advocates tout lower disease-specific death rates. Viz, mammography may (slightly) lower the chance of dying from breast cancer but it has no significant effect on all-cause death. Through a colleague [Dr. B. Mazer] on Twitter, I found a wonderful quote on the folly of trying to reduce your risk of dying from one sort of disease. “If you are a patient contemplating some screening test, and the result of that test or treatment is no measurable reduction in the rate of death at some clinically relevant later point in time, then why have the test or treatment—unless the patient, for some reason, has a desire to die from condition A instead of condition B.”

And excerpts from his commentary on this topic at Medscape: Want More Trust in Medical Science? Embrace Uncertainty and Cut the Hype

I see a lot of overconfidence in medical science. At the bedside, clinicians—myself included—underestimate harms and overestimate benefits of medical intervention. These inaccuracies have many causes. One is a lack of skepticism. It was 10 years into practice before I learned that most of a study's bias comes in its planning, in the questions it asks.

Rarely do I hear a practicing colleague or speaker at a medical meeting cite Dr John Ioannidis's famous 2005 paper "Why most published research findings are false." Ioannidis, a Stanford epidemiologist, argues that small sample sizes, tiny treatment effects, "flexible" study designs (which can transform "negative" into "positive" results), prestudy biases, and conflicts of interest are the root causes of false research findings. Research findings, he argues, may simply be an accurate measure of the prevailing bias.....Richard Horton, the editor of the Lancet, agrees with Ioannidis. In 2015, he wrote that "much of the scientific literature, perhaps half, may simply be untrue." One of the (many) reasons for this crisis, Horton adds, is that "in their quest for telling a compelling story, scientists too often sculpt data to fit their preferred theory of the world." 

Another group of academics that threaten the public trust are screening evangelists. Screening is precarious because it puts doctors close to breaking the golden rule—first, do no harm. Doing things to people-without-complaints and promoting the slogan "screening saves lives" should require clearing the highest bar of evidence. The truth, though, is that the evidence does not support such zealous advocacy.

A systematic review of meta-analyses and randomized clinical trials that studied screening of asymptomatic adults for 19 diseases (39 tests, including mammography) found reductions in disease-specific mortality were uncommon and reductions in all-cause mortality were very rare or nonexistent. Prasad and colleagues explain how screening advocates conflate disease-specific death rates with overall mortality. "Using disease-specific mortality as a proxy for overall mortality," they wrote in the BMJ, "deprives people of information about their chief concern: reducing the risk of dying."

Another good Dr. John Mandrola post: Four Crucial Questions To Ask Your Doctor

Mediterranean Diet is Healthy Eating – A Good Option for Seniors An article was just published in a research journal to discuss the fact that humans - in part due to lifestyles which include less dietary fiber (due to eating fewer varieties and amounts of plants) and due to medical practices (such as frequent use of antibiotics) has resulted in gut "bacterial extinctions". In other words, humans (especially those living an urban industrialized Western lifestyle) have fewer gut bacterial species than those living a more traditional lifestyle, and this loss of bacterial species is linked to various diseases. Humans can increase the number of certain bacterial species, but the loss of some bacterial species is forever. 

The researchers discuss that humans have the "lowest level of gut bacterial diversity"  of any hominid and primate. They stated that the shrinking of the variety of microbial species in the human gut (the gut microbiome) began early in human evolution (as humans started eating more meat), but that it has accelerated dramatically within industrialized societies. And that evidence is accumulating that this gut bacterial "depauperation" - the loss of a variety of bacterial species - may predispose humans to a range of diseases.  Some of it is due to evolution (as humans ate more meat), and some to lifestyle changes. A term is used throughout this paper: depauperate - which means lacking in numbers or variety of species in the gut microbiome (the microbial community or ecosystem).

Other research has also shown that eating a highly processed Western diet results in gut microbial changes that are linked to various diseases (here, here, here) - that is, the microbes being fed are those associated with diseases. Also, certain diets encourage certain microbial species to flourish (here, here).  Bottom line: studies find health benefits from higher levels of dietary fiber - from fruits, vegetables, seeds, nuts, whole grains, and legumes (beans). From Current Opinion In Microbiology:

The shrinking human gut microbiome

Highlights: Humans harbor the lowest levels of gut bacterial diversity of any hominid. Humans in industrialized nations harbor fewer gut bacterial taxa than any primate. Medical practices and lack of dietary fiber may drive gut bacterial extinctions. Depauperate microbiotas may predispose entire human populations to certain diseases.

Mammals harbor complex assemblages of gut bacteria that are deeply integrated with their hosts’ digestive, immune, and neuroendocrine systems. Recent work has revealed that there has been a substantial loss of gut bacterial diversity from humans since the divergence of humans and chimpanzees. This bacterial depauperation began in humanity’s ancient evolutionary past and has accelerated in recent years with the advent of modern lifestyles. Today, humans living in industrialized societies harbor the lowest levels of gut bacterial diversity of any primate for which metagenomic data are available, a condition that may increase risk of infections, autoimmune disorders, and metabolic syndrome. Some missing gut bacteria may remain within under-sampled human populations, whereas others may be globally extinct and unrecoverable.

A typical human harbors on the order of 1013 bacterial cells in the large intestine. This gut microbiota, which can contain over a thousand species, is deeply integrated with virtually every tissue and organ system in the body. Gut bacteria process difficult to digest components of the diet, promote angiogenesis in the intestine, train the immune system, regulate metabolism, and even influence moods and behaviors.

In contrast to hunter–gatherer to agricultural transitions, adoptions of industrial and post-industrial lifestyles have led to massive reductions in bacterial richness within human gut microbiotas. Individuals living in urban centers in the United States harbor fewer gut bacterial species on average than do individuals living more traditional lifestyles in Malawi , Venezuela, Peru, and Papua New Guinea.....Industrialized and traditional lifestyles differ in many respects, confounding the identification of the specific practices that have led to decreases in gut bacterial diversity within industrialized societies. One potential cause is the rise of food processing and the corresponding reductions in the intake of dietary fiber in favor of simple sugars. Recently, studies in model systems have indicated that long-term reductions in dietary fiber can lead to the extirpation of gut bacterial taxa from host lineages. 

Other potential causes of reduced gut bacterial diversity within industrialized human populations include certain modern medical practices. For example, longitudinal studies in humans have shown that levels of gut bacterial diversity decrease drastically after antibiotic use. Although bacterial richness may recover after treatment is completed, the timeline and extent of the restoration is highly subject-dependent. The consequences of antibiotic use on gut bacterial diversity may be most severe when treatment is administered during the early years of life, before the adult microbiota has fully formed .

 An interesting study looked at what the act of walking does to our brain, and found that it can modify and increase the amount of blood that’s sent to the brain (which is viewed as beneficial for brain function). The study, performed by researchers at New Mexico Highlands University in the United States, found that the foot’s impact on the ground while walking sends pressure waves through the arteries, which can increase the blood supply to the brain. This is referred to as cerebral blood flow or CBF.

These results may help explain other studies that find those that walk frequently (about 6 to 9 miles per week) have "less cognitive impairment" or cognitive decline, fewer memory problems, and greater brain volume with aging.  Another good reason to get out and walk - good for the heart, the body, and the brain. From Science Daily:

How walking benefits the brain

You probably know that walking does your body good, but it's not just your heart and muscles that benefit. Researchers at New Mexico Highlands University (NMHU) found that the foot's impact during walking sends pressure waves through the arteries that significantly modify and can increase the supply of blood to the brain. The research will be presented today at the APS annual meeting at Experimental Biology 2017 in Chicago.

Until recently, the blood supply to the brain (cerebral blood flow or CBF) was thought to be involuntarily regulated by the body and relatively unaffected by changes in the blood pressure caused by exercise or exertion. The NMHU research team and others previously found that the foot's impact during running (4-5 G-forces) caused significant impact-related retrograde (backward-flowing) waves through the arteries that sync with the heart rate and stride rate to dynamically regulate blood circulation to the brain.

In the current study, the research team used non-invasive ultrasound to measure internal carotid artery blood velocity waves and arterial diameters to calculate hemispheric CBF to both sides of the brain of 12 healthy young adults during standing upright rest and steady walking (1 meter/second). The researchers found that though there is lighter foot impact associated with walking compared with running, walking still produces larger pressure waves in the body that significantly increase blood flow to the brain. While the effects of walking on CBF were less dramatic than those caused by running, they were greater than the effects seen during cycling, which involves no foot impact at all.

 This post is more on the theme of nanoparticles and human health. My last post was about a study that examined how inhaled nanoparticles  (for example, from air pollution) travel from the lungs to the bloodstream. Well, today's post is about a pretty shocking 2016 air pollution nanoparticle study which examined the brains (brain tissue) of 45 dead people  (ages 3 to 92) who had lived for a long time in two places with heavy  particulate air pollution - Mexico City and Manchester, England. Some of the British people also had Alzheimer's disease or dementia.

The researchers found evidence that minute nano-sized particles of magnetite from air pollution can find their way into the brain. There are 2 forms of magnetite (which is an iron ore) - one naturally occurring (jagged edges in appearance), and one found commonly in air pollution (smooth and rounded - from being created in the high temperatures of vehicle engines or braking systems). The researchers are concerned that the air pollution nanoparticles may increase the risk for brain diseases such as Alzheimer's.

One of the researchers (Prof Barbara Maher) has previously identified magnetite particles in samples of air gathered beside a busy road in Lancaster, England and outside a power station. She suspected that similar particles may be found in the brain samples, and that is what happened. "It's dreadfully shocking. When you study the tissue you see the particles distributed between the cells and when you do a magnetic extraction there are millions of particles, millions in a single gram of brain tissue - that's a million opportunities to do damage."..."It's a whole new area to investigate to understand if these magnetite particles are causing or accelerating neurodegenerative disease." However, it must be stressed that at this time there is no proven link between these magnetite particles and any neurodegenerative diseases. They're just wondering.... they call finding these pollution nanoparticles "suggestive observations".

From Medical Xpress: Toxic air pollution nanoparticles discovered in the human brain

Tiny magnetic particles from air pollution have for the first time been discovered to be lodged in human brains – and researchers think they could be a possible cause of Alzheimer's disease. Researchers at Lancaster University found abundant magnetite nanoparticles in the brain tissue from 37 individuals aged three to 92-years-old who lived in Mexico City and Manchester. This strongly magnetic mineral is toxic and has been implicated in the production of reactive oxygen species (free radicals) in the human brain, which are associated with neurodegenerative diseases including Alzheimer's disease.

Professor Barbara Maher, from Lancaster Environment Centre, and colleagues (from Oxford, Glasgow, Manchester and Mexico City) used spectroscopic analysis to identify the particles as magnetite. Unlike angular magnetite particles that are believed to form naturally within the brain, most of the observed particles were spherical, with diameters up to 150 nm, some with fused surfaces, all characteristic of high-temperature formation – such as from vehicle (particularly diesel) engines or open fires. The spherical particles are often accompanied by nanoparticles containing other metals, such as platinum, nickel, and cobalt.

Professor Maher said: "The particles we found are strikingly similar to the magnetite nanospheres that are abundant in the airborne pollution found in urban settings, especially next to busy roads, and which are formed by combustion or frictional heating from vehicle engines or brakes."

Other sources of magnetite nanoparticles include open fires and poorly sealed stoves within homes. Particles smaller than 200 nm are small enough to enter the brain directly through the olfactory nerve after breathing air pollution through the nose.....The results have been published in the paper 'Magnetite pollution nanoparticles in the human brain' by the Proceedings of the National Academy of Sciences.

A good discussion of the study in The Scientist: Environmental Magnetite in the Human Brain

Fig. S11. Image of magnetite nanoparticles from the exhaust plume of a diesel engine. Credit: Maher et al study, 2016.

09_05_magnetic_01  A microscopic image shows magnetic nanoparticles in the human brain. Credit: Barbara Maher et al study, 2016.

  The use of nanomaterials has been really increasing  in recent years without us really understanding if  nanoparticles have negative health effects, and if they travel to the brain or other organs in the human body. Nanoparticles are used in many  consumer products, including foods (e.g., nano-sized titanium dioxide) and medicines, but they are also found in air pollution  (e.g., tires breaking down, vehicle exhaust). Well..... evidence is starting to appear that YES - nanoparticles can travel  throughout the body, and they can accumulate in the body, including lungs and brain, and they can have negative health effects. For example, inhaled nanoparticles from air pollution are able to deposit deep in the lungs where they cause oxidative stress and inflammation.

Now new research in both humans and mice has shown that inhaled nanoparticles can travel from the lungs into the bloodstream. In this study both healthy males and heart disease patients inhaled gold nanoparticles of varying sizes. The gold was detected in the blood and urine within 15 minutes to 24 hours after exposure, and was still present 3 months after exposure. The levels were greater following inhalation of smaller 5 nanometer (nm) particles compared to the larger 30 nm particles (meaning the body had trouble clearing the smaller nanoparticles). The nanoparticles acculmulated more in inflamed vascular sites, including carotid plaques in patients at risk of a stroke. Showing this is important in explaining how tiny nanosized particles in air pollution are linked to cardiovascular disease and death - for example, why and how they can trigger heart attacks and other "cardiovascular events". Science Daily:

Nanoparticles can travel from lungs to blood, possibly explaining risks to heart

Tiny particles in air pollution have been associated with cardiovascular disease, which can lead to premature death. But how particles inhaled into the lungs can affect blood vessels and the heart has remained a mystery. Now, scientists have found evidence in human and animal studies that inhaled nanoparticles can travel from the lungs into the bloodstream, potentially explaining the link between air pollution and cardiovascular disease. Their results appear in the journal ACS Nano.

The World Health Organization estimates that in 2012, about 72 percent of premature deaths related to outdoor air pollution were due to ischemic heart disease and strokes. Pulmonary disease, respiratory infections and lung cancer were linked to the other 28 percent. Many scientists have suspected that fine particles travel from the lungs into the bloodstream, but evidence supporting this assumption in humans has been challenging to collect. So Mark Miller and colleagues at the University of Edinburgh in the United Kingdom and the National Institute for Public Health and the Environment in the Netherlands used a selection of specialized techniques to track the fate of inhaled gold nanoparticles.

In the new study, 14 healthy volunteers, 12 surgical patients and several mouse models inhaled gold nanoparticles, which have been safely used in medical imaging and drug delivery. Soon after exposure, the nanoparticles were detected in blood and urine. Importantly, the nanoparticles appeared to preferentially accumulate at inflamed vascular sites, including carotid plaques in patients at risk of a stroke. The findings suggest that nanoparticles can travel from the lungs into the bloodstream and reach susceptible areas of the cardiovascular system where they could possibly increase the likelihood of a heart attack or stroke, the researchers say. [Original study.]

Mediterranean Diet is Healthy Eating – A Good Option for Seniors Another large recent study found that lowering sodium intakes (less than 2500 milligrams per day) wasn't linked to lower blood pressure. Over the course of 16 years, the researchers found that the study participants who consumed less than 2500 milligrams of sodium a day had higher blood pressure than participants who consumed higher amounts of sodium. However, the current 2015-2020 Dietary Guidelines for Americans recommends limiting sodium intake to 2,300 grams a day for healthy people. The researchers felt that based on recent studies with similar findings that the sodium guidelines should be changed.

This 16 year study found that people in the study who had normal intakes of sodium, but also higher intakes of potassium, calcium and magnesium exhibited lower blood pressure over the course of the study. And those people with higher combined intakes of sodium (3717 milligrams per day on average) and potassium (3211 milligrams per day on average on average) had the lowest blood pressure.

Some good potassium foods:  avocado, winter squash, sweet potato, potato, white beans, banana, spinach, salmon, dried apricots, tomato sauce, beans, and milk. Some good magnesium foods: dark leafy greens, nuts, seeds, fish, beans, whole grains, avocados, yogurt, bananas, dried fruit, dark chocolate. Some good calcium foods: milk, cheese, yogurt, kale, sardines, broccoli, white beans, and rhubarb. From Science Daily:

Low-sodium diet might not lower blood pressure: Findings from large, 16-year study contradict sodium limits in Dietary Guidelines for Americans

A new study that followed more than 2,600 men and women for 16 years found that consuming less sodium wasn't associated with lower blood pressure. The new findings call into question the sodium limits recommended by the current Dietary Guidelines for Americans. Lynn L. Moore, DSc, associate professor of medicine at Boston University School of Medicine, will present the new research at the American Society for Nutrition Scientific Sessions and annual meeting during the Experimental Biology 2017 meeting, to be held April 22-26 in Chicago.

"We saw no evidence that a diet lower in sodium had any long-term beneficial effects on blood pressure," said Moore. "Our findings add to growing evidence that current recommendations for sodium intake may be misguided." The 2015-2020 Dietary Guidelines for Americans recommends limiting sodium intake to 2,300 grams a day for healthy people. For the study, the researchers followed 2,632 men and women ages 30 to 64 years old who were part of the Framingham Offspring Study. The participants had normal blood pressure at the study's start. However, over the next 16 years, the researchers found that the study participants who consumed less than 2500 milligrams of sodium a day had higher blood pressure than participants who consumed higher amounts of sodium.

Other large studies published in the past few years have found what researchers call a J-shaped relationship between sodium and cardiovascular risk -- that means people with low-sodium diets (as recommended by the Dietary Guidelines for Americans) and people with a very high sodium intake (above the usual intake of the average American) had higher risks of heart disease. Those with the lowest risk had sodium intakes in the middle, which is the range consumed by most Americans.

The researchers also found that people in the study who had higher intakes of potassium, calcium and magnesium exhibited lower blood pressure over the long term. In Framingham, people with higher combined intakes of sodium (3717 milligrams per day on average) and potassium (3211 milligrams per day on average on average) had the lowest blood pressure.....Moore says that there is likely a subset of people sensitive to salt who would benefit from lowering sodium intake, but more research is needed to develop easier methods to screen for salt sensitivity and to determine appropriate guidelines for intakes of sodium and potassium in this salt-sensitive group of people.

Image result for earth wikipedia On this Earth Day I want to say: Support science. Support the work of scientists. Science is the pursuit of knowledge. Science is about facts and evidence - not opinions. Medicine is applied science - scientific discoveries are turned into real-world medical treatments. Yes, scientific theories and what we know in science and medicine can change over time as more evidence is found. But science is not political, or it shouldn't be political. This is because we all benefit from science and scientific knowledge.

Sometimes there is bias in science (as when scientists receiving money from a corporation or working for a corporation then do research with results desired by that corporation), but that is why it is important to have transparency in research studies and results, and why good research involves peer review (other scientists review the research) and open discussion, and the importance of others having similar research results in an area. This is also why government funding of basic research is important.

Science is a process of understanding how the world works - it is curiosity driven and uses empirical evidence, particularly information acquired by observation and experimentation. Data is recorded and analyzed by scientists and is part of the scientific method. Basic science results in discoveries that may lead to incredible uses down the road and to amazing benefits to society. An example is the discovery of penicillin, which eventually changed medicine. Government funding has supported basic science for years - for example, NASA, National Oceanic and Atmospheric Administration, National Institutes of Health, and the National Science Foundation. Without government support, most basic scientific research will never happen.

Basically every post I've ever done is science based. Even the ones on sinusitis, Lactobacillus sakei, and the results of self-experimentation. And yes, self-experimentation in science and medicine has a long and honorable history. A very famous example was when the Australian physician Barry Marshall drank a petri dish containing Helicobacter pylori bacteria (from a patient) and soon developed the symptoms of peptic ulcer - this led to his eventually being awarded the Nobel Prize in 2005.

Similarly, through self-experimentation - my four family members, as well as many people writing to me, have reported amazing results within days of using a L. sakei product without changing anything else in their lives. These self-experiments were based on scientific evidence presented in the original Abreu et al study (2012) on sinusitis and the sinus microbiome. This is science at its most basic: doing "A" to a person with condition "B" and seeing the result "C" (which can be a positive effect, no effect, or negative effect).

So take a moment and appreciate all the different fields of science and how they have changed our lives: oceanography, chemistry, physics, earth science, ecology, geology, meteorology, astronomy, zoology, human biology (includes microbiology, anatomy, neurology, immunology, genetics, physiology, pathology, and ophthalmology), botany, anthropology, archaeology, criminology, psychology, sociology, computer science, statistics, mathematics, etc. Some areas of applied science are: engineering, computer science, and medicine. Wow....So please...Support science and the pursuit of knowledge. It's not political. It's not opinions or wishful thinking. Don't deny science.

I think everyone needs to laugh at the silly side of life sometimes. With that said, I am offering the following (all from The New Yorker archives) about health and food:

Image result for bacteria, new yorker "Throw out the hummus - from now on, we only eat food too fake to host bacteria."

Image result for kale, new yorker

Image result for health cartoon new yorker

Cartoon  “He’s allergic to peanuts, sensitive to wheat, lactose-intolerant, and just plain weirded out by fruit.”

Image result for diseases new yorker "But why not be happy about all the diseases you don't have?"

Image result for diet cartoon new yorker

Image result for exercisecartoon new yorker "Be honest - how much are you exercising?"

Image result for glasbergen cartoon, I'm writing you a prescription Credit: R. Glasbergen