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The Paleo diet has been around for years and yet it continues to be controversial. The debate is whether following the Paleo diet long-term has health benefits or not? Supporters of the Paleo (Paleolothic) diet say it promotes gut health and is good for gut microbes, but recent research findings are a strike against this claim. The Paleo diet is based on the hypothesis that humans have not adapted to eating products of agricultural farming such as grains, dairy products, or legumes (beans), as well as all processed foods, so they should be avoided. Instead it stresses eating meat, fish, eggs, nuts, (some) fruits, and vegetables.

So what were the new research findings?  Australian researchers found that people who had been on a Paleo diet for more than a year ate lower amounts of resistant starch, and so had a different bacteria profile in the gut - with lower levels of some beneficial species. They also had high levels of a biomarker in the blood (trimethylamine-n-oxide or TMAO) that is linked to heart disease.

The problem seems to be the lower intake of resistant starch - which is a carbohydrate that resists digestion in the small intestine and ferments in the large intestine. As the fibers ferment they act as a prebiotic and feed the beneficial bacteria in the gut. More than one type of resistant starch can be present in a single food. And what foods contain resistant starches? Precisely some foods avoided in the Paleo diet: grains, rice, beans, peas, lentils, plantains, and green bananas. A number of studies find health benefits (e.g. gut health) from eating foods with resistant starches.

From Medical Xpress: Heart disease biomarker linked to paleo diet

People who follow the paleo diet have twice the amount of a key blood biomarker linked closely to heart disease, the world's first major study examining the impact of the diet on gut bacteria has found.  ...continue reading "Problems With Paleo Diet?"

New research once again confirms that raw fruits and vegetables result in a person ingesting lots of microbes. Millions of bacteria. Which is considered beneficial for our gut microbiome! What's interesting in the latest study looking at bacteria in both conventionally and organically grown apples is that organic apples are a better source of bacteria - that their bacteria are more diverse, distinct, and balanced (when compared to conventionally grown apples).

The Austrian researchers (Wassermann et al) wrote in the Frontiers In Microbiology: "Our results suggest that we consume about 100 million bacterial cells with one apple. Although this amount was the same, the bacterial composition was significantly different in conventionally and organically produced apples."

Interestingly, there were a lot of beneficial Lactobacillus species in the organic apples, but not conventionally grown ones. The researchers thought that the diverse microbiome of organic apples probably limits or hampers harmful microbes (human pathogens). The researchers also wrote: "The described microbial patterns in organic apples resemble the impact of apple polyphenols on human health, which have not only been shown to alleviate allergic symptoms (Zuercher et al., 2010), but also to promote growth of Lactobacillus and Bifidobacterium in the human gut and to reduce abundance of food-borne pathogens."

Another bonus of eating organic apples is that it means avoiding pesticides that are routinely sprayed on conventional fruit. So eat away! Microbes, fiber, and nutrients all in one small fruit!

Fun fact: The researchers write that apples are the most consumed fruit world-wide. Excerpts from Science Daily: An apple carries about 100 million bacteria -- good luck washing them off  ...continue reading "Excellent Reason To Eat Apples: The Bacteria"

Once again research is finding effects on health from nanoparticles and air pollution - this time the heart. Tiny air pollution particles less than 100 nm (nanometers) in size are typically called "ultrafine  particles", but actually they are so small that they are nanoparticles. They are NOT regulated in the United States, even though many researchers feel that they are the most dangerous particles found in air pollution. This is because their small size means they are easily inhaled and then get into human lungs and organs, and even cells. Where do they come from? They get into the air from industry (e.g. metal processing, power generation plants), from the exhaust of vehicles (from vehicle combustion), and from friction when using vehicle brakes.

The researchers write that the air in polluted urban areas and next to roads have a lot of these iron-rich nanoparticles from vehicle combustion and friction. And also that these particles are "strongly magnetic". Earlier research in the urban Mexico City area found that these nanoparticles were found in the brains of all people, starting at young ages (they had died suddenly in accidents, which is why the brains could be analyzed). Keep in mind that Mexico City has high levels of air pollution, but so do many other urban areas throughout the world.

This latest study from a team of international researchers analyzed both the hearts of young people who died suddenly, as well as animals - and they compared the results from those exposed to high levels of urban air pollution (Mexico City metro area) and those from areas with low amounts of air pollution (the "controls"). The results were not good: all hearts from the Mexico City area (high air pollution) had lots of the same iron-rich magnetic nanoparticles ("in abundance") that are found in the air. Billions of nanoparticles in each heart, even in the youngest 3 year old child!

These nanoparticles are inhaled, then enter the person's circulatory system (carried by blood cells), and then into cardiac cells. As the researchers stated: the magnetic nanoparticles were "highly abundant in left ventricular samples from young subjects exposed to high concentrations of particulate air pollution above current US EPA standards. The organelles and structures containing abundant nanoparticles displayed substantial abnormality". Hearts from low pollution areas appeared normal.

This could explain why people living in polluted urban areas, including in the United States, have a greater risk for heart disease (cardiovascular disease), including heart attacks and strokes, as well as premature death. This research also highlights why we need to regulate these tiny particles in the air. As the researchers said: "This is a serious public health concern".

Excerpts from The Guardian: Billions of air pollution particles found in hearts of city dwellers   ...continue reading "Pollution Nanoparticles Found In Human Hearts"

We tend to think of our beds as a refuge from the outside world, where one can safely relax and sleep. Well... not quite. A recent study conducted in Israel analyzed chemicals released from youth and infant polyurethane mattresses and found that all the mattresses outgassed chemicals of concern (such as formaldehyde, toluene, benzene). These chemicals are called VOCs (volatile organic compounds) - they are chemical compounds released from products (e.g. mattresses) as vapor into the air, which we then breathe in. It is known that some VOCs have harmful health effects (e.g. eye and nose irritation, neurological effects, cancer) at high levels long-term. The researchers also found that a person's body heat on the mattress actually increases release of chemicals.

The one infant mattress tested also released flame retardants into the air. Of course no one really knows what breathing in low levels of these chemicals night after night for years does to us, if anything. But it should concern us. Keep in mind that during sleep our mouths and nostrils are very close to the mattress surface, so we are definitely breathing in whatever chemicals our mattresses emit. Researchers referred to the air around our beds as our sleeping microenvironment. And yes, our bedding (sheets, etc) also emit chemicals that they were treated with during manufacturing, such as formaldehyde in wrinkle-free sheets.

From Science Daily: Mattresses could emit higher levels of VOCs during sleep

Hundreds of household items, including furniture, paint and electronics, emit volatile organic compounds (VOCs), which at high levels can pose health risks. Now, researchers reporting in ACS' Environmental Science & Technology have measured the emission rates of the gaseous compounds released by several types of polyurethane mattresses under simulated sleeping conditions, finding levels of some VOCs that could be worrisome for children and infants. However, so far there is no evidence of adverse health effects.  ...continue reading "Mattresses Emit Chemicals"

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

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

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

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


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

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

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

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

Want to prevent your children from having allergies or asthma? A recent study adds support to increasing evidence that growing up on a farm, or living among multiple pets in the first year of life is protective against developing allergies and asthma. This is because exposure to lots of animal and outdoor soil bacteria in early childhood is good for the developing immune system. The study, which was conducted by Finland's National Institute  of Health and Welfare, carried this line of work further and found that this type of beneficial farm microbial exposure could be duplicated in non-farm homes.

They found that children's risk of developing asthma decreased as the similarity of their home's bacteria became more similar to that of farm homes. The researchers analyzed living room dust from homes and found that certain types of outdoor soil microbes were beneficial for preventing asthma. They found higher levels of these bacteria (and archaea, another microbe) in homes where people wore their outdoor shoes in the house, as well as 3 or more children, and increased moisture in houses. The types of fungi found in the dust of farm and non-farm houses didn't seem to matter. The researchers mention that the same kind of protective (for asthma) results of soil microbes has also been shown in mice.

Additional thoughts reading this: The study results can be interpreted as playing and crawling outdoors is definitely beneficial to children's health, especially young children. Exposure to soil microbes! And, of course, having pets. But wearing outdoor shoes indoors is problematic in areas with high lawn and garden pesticide use (e.g. suburban NY and NJ!) because studies show the pesticides get tracked indoors. This same problem occurs in areas with high lead levels (around older homes) or other heavy metals.

From Science Daily: Farm-like indoor microbiota may protect children from asthma also in urban homes   ...continue reading "Outdoor Soil Microbes In the Home and Asthma"

More bad news about the toxic class of chemicals called PFAS chemicals, which are used in a wide variety of consumer products, such as Teflon non-stick cookware and Scotchgard. The problem is that the chemicals don't stay in the products, but leach out (migrate out) and spread further - even into us. Unfortunately these chemicals persist in the environment. Earlier studies had already detected PFAS  (per- and polyfluoroalkyl substances) chemicals in water, soil, some foods, and in the bodies of almost all Americans. Now some recent research studies and the efforts of investigative journalists have uncovered more disturbing findings about the spread of these chemicals in the environment, in foods, and us.

The site Intercept has done a series of investigative reports highlighting these new findings about PFAS chemicals For example, these chemicals are found in fertilizers that contain sewage sludge (or biosolids) that farmers use on their farms. Farmers have been been doing this for decades. And it's in milk from dairy farms that spread this compost (fertilizer) made from sewage sludge on their fields. Of course! What is spread on the fields gets into food and which humans then ingest. The chemicals are also found in breastmilk from women in every country that has been studied.

Environmental Working Group (EWG) also has a series of articles on these chemicals, including the results of a recent FDA study of foods. The FDA found PFAS in many foods, including meat, seafood, dairy products, sweet potatoes, pineapples, leafy greens, and chocolate cake with icing. But the FDA has not publicly disclosed the results. Why not? Especially since the EPA has already said that "dietary exposure" (what we eat) is a main way that people get these chemicals into their bodies.

Why should we be concerned? PFAS chemicals are called  by some as "persistant chemicals" because of their persistence in the environment and humans. PFAS chemicals are linked to all sorts of serious health risks, including reproductive harm (e.g.poorer semen quality), cancers, lowered sex and growth hormones in children, immune effects,  thyroid disease, liver and kidney damage, and high cholesterol.

PFAS chemicals (such as PFOA, PFOS, PFBS) are used in a wide variety of consumer products because they have stain, water, and grease repellent properties. They are used in nonstick cookware, in food packaging (especially the paper wrappers and cardboard containers), stain-resistant carpets, furniture, floor waxes, textiles, water-proof and stain-resistant clothing (such as Gore-tex fabric), and performance gear. Remember Teflon? That's one. Some have been banned, phased out of use because of their dangers, but the replacements appear to be just as bad. The chemicals migrate out of food packaging into food, or can be released into the air and dust from carpets and upholstery treated with stain-resistant coatings.

I want to point out that sewage sludge (also called biosolids), are found in many commonly available fertilizers, such as Milorganite fertilizer.  It's not just farmers who've been using the stuff for years. Note that organic fertilizers and organic farmers can NOT use sewage sludge (biosolids). It turns out that even compostable food containers contain PFAS chemicals that leach out. Yikes!

What can you do to lower exposure to PFCs? These are chemicals that are hard to totally avoid, but one can lower exposure to them. And some have been phased out. The good news is that research shows that after a while levels in blood and breast milk should drop. What to do?? First of all, don't use non-stick pots and pans, and definitely not older Teflon ones. Use stainless steel or cast iron instead. Avoid the use of non-stick smooth dental floss made with a "non-stick" coating such as Oral-B Glide dental floss (use plain waxed or unwaxed floss instead). Try to not eat prepared foods in coated containers frequently. Avoid Scotchgard or other stain-proofing or stain-resistant treatments on upholstered furniture or rugs. Avoid water-proof treated fabric. It's also best to avoid drinking PFAS-contaminated water (which may be hard to do in places such as NJ where so much of the water supply is contaminated by PFAS chemicals).

From the Intercept - TOXIC PFAS CHEMICALS FOUND IN MAINE FARMS FERTILIZED WITH SEWAGE SLUDGE ...continue reading "Why Are We Still Using These Dangerous Substances In Consumer Products?"

What's with the blueberry obsession in medical studies? Another study finding health benefits with frequent eating of blueberries was recently published in the American Journal of Clinical Nutrition. Researchers at the Univ. of Anglia in the United Kingdom found that eating one cup of blueberries daily for 6 months reduced risk factors for cardiovascular disease (e.g. improvements in endothelial function, systemic arterial stiffness, and HDL cholesterol concentrations). They predicted that this would result in 12 to 15% reductions in heart (cardiovascular) disease risk.

The nicely done study was conducted on 138 overweight or obese men aged 50 to 75 years, all with Metabolic syndrome (e.g. hypertension, low levels of HDL cholesterol, impaired fasting glucose) - thus a group at risk for heart disease. Interestingly, ingesting 1/2 cup of blueberries a day did not have health benefits  - only 1 cup of blueberries a day did. So it was dose dependent -the more, the better. However, the study did not find any improvements in blood pressure or insulin resistance (glucose control) at the end of 6 months.

Remember, one should not focus on individual foods (e.g. blueberries), but should strive for a good dietary pattern, such as the Mediterranean diet. That means a diet rich in fruits and vegetables, whole grains, seeds, nuts, and legumes. These foods have lots of fiber and feed the beneficial microbes in the gut. Eating one beneficial food such as blueberries won't overcome an entire unhealthy dietary pattern, such as the Western one (lots of highly processed foods, low in fiber, lots of fast food, sugary drinks, etc).

BOTTOM LINE: While this study focused on blueberries, research shows that eating all types of berries (blueberriesblackberries, raspberries, lingonberries, bilberries, strawberries, etc.) have health benefits. One should actually try eating a variety of berries, if possible, because they all have different nutrients, microbes (to feed beneficial bacteria in the gut), and different health benefits.

From Medical Xpress: Eating blueberries every day improves heart health   ...continue reading "Eating Blueberries Frequently and Heart Health"

There has been much discussion recently over why the incidence of allergies and chronic diseases is rising in Western industrialized countries. Some theories have been proposed, such as the hygiene hypothesis (that early childhood environments are too sterile and so that the developing immune system isn't properly "trained"), or that medicines such as antibiotics kill off beneficial bacteria, whille others say it is due to our Western diet and lifestyle. However, recently some researchers have proposed that the absence of intestinal worms, called helminths, in our bodies is actually negative for our health and could be a reason for the rising incidence of allergies and these diseases.

Over the centuries intestinal worms (such as hookworms) have caused a lot of human suffering, and therefore have been viewed as disease causing parasites. Western industrialized countries made major efforts (such as improved sanitation) to get rid of all intestinal worms in humans, and were generally successful. It is now rare to hear of someone in these countries having intestinal worms.

Dr. William Parker, an associate professor of surgery at Duke University in North Carolina, has written an interesting and thought-provoking article about the role of helminths in human health. He states: "A barrage of scientific evidence points toward helminths as being important regulators of immune function." In other words, we need them in order for our immune system to function properly.

Research actually shows that introducing certain species of intestinal worms, such as roundworms or flatworms, into the human gut successfully treats certain diseases in humans. But medicine has been slow to adopt such a view. Dr. Parker writes that viewing certain helminths as beneficial for proper immune functioning would be a "paradigm shift" in medicine.

By the way, the research looking at intestinal worms found benefits from low levels of helminths, not huge amounts. Having higher levels of helminths (such as roundworms) results in various symptoms (e.g. fever, abdominal pain, diarrhea)

Do go read the full article. Excerpts are from Dr. William Parker's article in Aeon: We Need Worms   ...continue reading "Will We Use Intestinal Worms To Treat Diseases?"