Skip to content

Another problem for overweight or obese men: an increased risk of poor sperm quality. Researchers in India found that compared to normal weight men, obesity was associated with lower sperm count, lower volume of semen, lower sperm concentration, poor sperm motility (the movement of sperm), as well as sperm defects. There is some evidence (from other studies and the researchers own work) that there is improvement in sperm quality with weight loss.

The researchers pointed out that other studies have shown that "paternal obesity at conception had deleterious effects on embryo health, implantation, pregnancy, and live birth rates." And that poor sperm quality is a cause of infertility. So.... what do the researchers recommend? Weight loss and exercise, and perhaps bariatric surgery, for obese men having fertility problems due to poor sperm quality. From Medical Xpress: 

As men's weight rises, sperm health may fall

A widening waistline may make for shrinking numbers of sperm, new research suggests. Indian scientists studied more than 1,200 men and found that too much extra weight was linked to a lower volume of semen, a lower sperm count and lower sperm concentration. In addition, sperm motility (the ability to move quickly through the female reproductive tract) was poor. The sperm had other defects as well, the researchers added. Poor sperm quality can lower fertility and the chances of conception.

"It's known that obese women take longer to conceive," said lead researcher Dr. Gottumukkala Achyuta Rama Raju, from the Center for Assisted Reproduction at the Krishna IVF Clinic, in Visakhapatnam. "This study proves that obese men are also a cause for delay in conception," he added.

But in continuing research, the study team is looking to see if losing weight will improve the quality of sperm. Although that study is still in progress, early signs look good that sperm quality improves as men lose weight, Rama Raju said. Recent reports have found that extreme weight loss after bariatric surgery reversed some of the sperm decline, he said.

For the study, Rama Raju and his colleagues used computer-aided sperm analysis to assess the sperm of 1,285 men. Obese men, they found, had fewer sperm, a lower concentration of sperm and inability of the sperm to move at a normal speed, compared with the sperm of men of normal weight. Moreover, the sperm of obese men had more defects than other sperm. These defects included defects in the head of the sperm, such as thin heads and pear-shaped heads.  [Original study.]

 Human sperm. Credit: Wikipedia

This is part 2 of posts about tiny particles of plastic (microfibers) in our water - which is a form of water pollution. These plastic fibers are smaller than 5 mm, and are found in water (drinking water, rivers, oceans) throughout the world. An investigative study by Orb Media (done by research scientists) took numerous drinking water samples from more than a dozen nations and analyzed them. They found that 83% of drinking water samples worldwide, and 94% of drinking water samples taken in the US (which included tap water from Congressional buildings, the US Environmental Protection Agency’s headquarters, Trump Tower in New York, and bottled waters) contained plastic microfibers.

The last post discussed  research finding plastic microfibers in rivers, and how they are now found in fish and shellfish - and so eventually in us (we eat fish and shellfish, don't we?). The plastic microfibers are in our food chain, and there is tremendous concern over what that is doing to wildlife and to us, especially as the microfibers accumulate. Well, we also now know that the plastic microfibers are found in drinking water, are in the air, and can be found in foods tested (even beer).

So what are these plastic microfibers doing to us? And how can we reduce the number of microfibers being released into the air? The Orb Media site discusses sources of plastic microfibers in the environment (from clothes being washed, tire dust, paint dust, etc.) to how we personally can generate fewer plastic microfibers (try not to use plastic bags or straws, etc.). Excerpts from The Guardian:

Plastic fibres found in tap water around the world, study reveals

Microplastic contamination has been found in tap water in countries around the world, leading to calls from scientists for urgent research on the implications for health. Scores of tap water samples from more than a dozen nations were analysed by scientists for an investigation by Orb Media, who shared the findings with the Guardian. Overall, 83% of the samples were contaminated with plastic fibres.

The US had the highest contamination rate, at 94%, with plastic fibres found in tap water sampled at sites including Congress buildings, the US Environmental Protection Agency’s headquarters, and Trump Tower in New York. Lebanon and India had the next highest rates. European nations including the UK, Germany and France had the lowest contamination rate, but this was still 72%. The average number of fibres found in each 500ml sample ranged from 4.8 in the US to 1.9 in Europe.

The new analyses indicate the ubiquitous extent of microplastic contamination in the global environment. Previous work has been largely focused on plastic pollution in the oceans, which suggests people are eating microplastics via contaminated seafood. “We have enough data from looking at wildlife, and the impacts that it’s having on wildlife, to be concerned,” said Dr Sherri Mason, a microplastic expert at the State University of New York in Fredonia, who supervised the analyses for Orb. “If it’s impacting [wildlife], then how do we think that it’s not going to somehow impact us?”

Mahon said there were two principal concerns: very small plastic particles and the chemicals or pathogens that microplastics can harbour. “If the fibres are there, it is possible that the nanoparticles are there too that we can’t measure,” she said. “Once they are in the nanometre range they can really penetrate a cell and that means they can penetrate organs, and that would be worrying.” The Orb analyses caught particles of more than 2.5 microns in size, 2,500 times bigger than a nanometre. [NOTE: This means they were not able to test for smaller sizes.]

The scale of global microplastic contamination is only starting to become clear, with studies in Germany finding fibres and fragments in all of the 24 beer brands they tested, as well as in honey and sugar. In Paris in 2015, researchers discovered microplastic falling from the air, which they estimated deposits three to 10 tonnes of fibres on the city each year, and that it was also present in the air in people’s homes.

How microplastics end up in drinking water is for now a mystery, but the atmosphere is one obvious source, with fibres shed by the everyday wear and tear of clothes and carpets. Tumble dryers are another potential source, with almost 80% of US households having dryers that usually vent to the open air. “We really think that the lakes [and other water bodies] can be contaminated by cumulative atmospheric inputs,” said Johnny Gasperi, at the University Paris-Est Créteil, who did the Paris studies. “What we observed in Paris tends to demonstrate that a huge amount of fibres are present in atmospheric fallout.”.... Plastic fibres may also be flushed into water systems, with a recent study finding that each cycle of a washing machine could release 700,000 fibres into the environment. Rains could also sweep up microplastic pollution, which could explain why the household wells used in Indonesia were found to be contaminated. 

Microfibers found in the Hudson River. Credit: PBS News Hour, Sara Cathey, Adventure Scientists

You may not think of your clothes as pollutants, but tiny plastic fibers from synthetic textiles (microfibers) are big contributors to water pollution. Clothes and fabrics made with synthetic fibers are using plastic fibers (e.g. polyester, nylon, acrylic, fleece and athletic clothing). When they are washed, they break apart in the washing machine, and so get into the wastewater system, and eventually into our rivers and oceans.

These microplastic particles are smaller than 5 mm. One 2011 study found that "Experiments sampling wastewater from domestic washing machines demonstrated that a single garment can produce greater than 1900 fibers per wash" (which then goes directly into wastewater). And while a 2017 study didn't examine sources of microfibers (air, rain, water treatment plants, etc) found in numerous Hudson River water samples, the researchers estimate that the entire Hudson River dumps 300 million human-made fibers into the Atlantic Ocean each day. Wow.

In the past few weeks a number of articles and studies have been published about these small plastic pieces (microfibers) that are found in our water - yes, in our drinking water, as well as our rivers, seas, and oceans. Which eventually get into birds, fish and shellfish - and so eventually into us. So the microfibers are in our food chain. There is tremendous concern over what that is doing to wildlife and to us, especially as the microfibers accumulate. We all use plastics every day and most of us wear clothing made of plastic fibers (synthetic fibers), and we're not about to stop. (NOTE: No matter what fabrics we wear, our clothing also sheds fibers into the air, so we leave a trail of fibers behind us, including at crime scenes. Synthetic and natural materials - such as cotton and wool, both shed.)

The big questions: Can anything be done to stop this water pollution? And what is it doing to us and wildlife? Today I am posting links to these stories because it is of concern to all of us and to future generations, and we need to think about and address this issue.

Excerpts from PBS News Hour: This New York river dumps millions of fabric microfibers into the ocean daily

The faded, “distressed look” of a favorite pair of blue jeans, may come with a hidden price for the residents of New York. The Hudson River dumps 300 million clothing fibers into the Atlantic Ocean each day, according to a recent study in the Marine Pollution Bulletin. Many of the fibers come from aging clothes, rinsed out with the laundry and into the environment. Approximately half of the fibers were plastic, while the remainder were spun from natural materials like cotton or wool. Invisible to the naked eye, these fibers can cause health problems for animals and humans.

Barrows, who has been studying microfiber pollution in oceans for more than five years, wanted to learn more about what’s happening upstream in freshwater. So last year, Barrows and a team of scientists and volunteers measured microfiber pollution across all 13,300 miles of the Hudson river..... The team found about one microfiber per liter of water, which seems small until you consider the sheer volume of the Hudson River. An average-sized, above-ground swimming pool filled with this water would contain about 10,800 microfibers, and the entire Hudson River dumps 300 million human-made fibers into the Atlantic Ocean each day. [Original Hudson River study.]

If wastewater treatment facilities are not the major culprit, people may want to look their everyday clothes. Fabrics cast off tiny threads at every stage of their life. Even crime scene investigators count on perpetrators leaving behind bits of clothing. “We are just not conscious of it,” Carr said. “It’s invisible, but everywhere you go and everywhere I go, we are leaving a trail of fibers in our wake.”

Pollutants and other fine particles can hang in the air and travel great distances, said George Thurston, who studies the health effects of air pollution at New York School of Medicine. These airborne fibers can also be toxic. During the industrial revolution, byssinosis or brown lung disease, befell textile plant workers due to cotton or other fibers in the factory’s air. But Thurston said more research is needed to ascertain how microfibers get around.

Microfibers found in the Hudson River. Credit: PBS News Hour, Sara Cathey, Adventure Scientists



An interesting article that describes the difficulty of capturing tiny plastic microfibers at sewage and water treatment plants in Minnesota. From MPR News: Microplastics could pose big treatment challenges

So-called microplastics are tiny — less than 5 millimeters across. They can come from litter or plastic bags that break down over time. ...."These small little threads, they find their way into the wastewater treatment system and then, into our aquatic environment."

Austin Baldwin, a hydrologist with the U.S. Geological Survey, studied the St. Croix, Namekagon and Mississippi rivers in 2015. The results were published earlier this year in a brief issued by the National Park Service. Baldwin's team found microplastics in all of the samples they took of water, sediment, fish and mussels. The level of concentration was surprising: They found as many as 111 microscopic pieces of plastic in a single fish. Scientists worry that microplastics might clog the digestive systems of fish and make them feel full, so they end up starving. Baldwin said there need to be more study of the biological impacts.

Microplastic fibers in the wastewater are so small they slip through filters and screens designed to capture larger particles. Hoellin's team sampled Chicago rivers and found higher concentrations of microplastics downstream of sewer plants. "What I've seen is that some wastewater treatment plants are really effective at retaining 99 percent of the microplastic that comes in as raw sewage," Hoellin said. "But even that 1 percent, when it's added up on a daily, yearly basis, is amounting to a lot of plastic pollution." Hoellin noted there's no legal requirement for wastewater plants to treat for microplastics. "

By the time the treated wastewater is discharged into the Mississippi River, Rogacki [Larry Rogacki, assistant general manager of the Metropolitan Wastewater Treatment Plant in St. Paul, MN] estimates that 96-98 percent of all microplastics have been removed. Retrofitting the plant to eliminate 100 percent of microplastics would require installing sand filters that could capture smaller particles, he said. It would be costly — close to $1 billion. ....What scientists say might be more effective — and less expensive — is to figure out how to keep plastic out of the wastewater stream in the first place.

A number of people contacting me have indicated that living in a house or apartment with a mold problem led to their chronic sinusitis. And it wasn't the dreaded toxic black mold (varieties of mold which can cause serious neurological symptoms), but common molds that triggered their inflammatory reactions, respiratory symptoms, allergies, and eventually chronic sinusitis. All due to excessive mold exposure.

This summer's flooding caused by hurricanes and tropical storms will result in major mold growth in residences after the water recedes. What will be the health consequences? Article excerpts about mold (and with impressive photos) from The Atlantic:

The Looming Consequences of Breathing Mold

But the impact of hurricanes on health is not captured in the mortality and morbidity numbers in the days after the rain. This is typified by the inglorious problem of mold. Submerging a city means introducing a new ecosystem of fungal growth that will change the health of the population in ways we are only beginning to understand. The same infrastructure and geography that have kept this water from dissipating created a uniquely prolonged period for fungal overgrowth to take hold, which can mean health effects that will bear out over years and lifetimes.

The documented dangers of excessive mold exposure are many. Guidelines issued by the World Health Organization note that living or working amid mold is associated with respiratory symptoms, allergies, asthma, and immunological reactions. The document cites a wide array of “inflammatory and toxic responses after exposure to microorganisms isolated from damp buildings, including their spores, metabolites, and components,” as well as evidence that mold exposure can increase risks of rare conditions like hypersensitivity pneumonitis, allergic alveolitis, and chronic sinusitis.

Twelve years ago in New Orleans, Katrina similarly rendered most homes unlivable, and it created a breeding ground for mosquitoes and the diseases they carry, and caused a shortage of potable water and food. But long after these threats to human health were addressed, the mold exposure, in low-income neighborhoods in particular, continued. The same is true in parts of Brooklyn, where mold overgrowth has reportedly worsened in the years since Hurricane Sandy. In the Red Hook neighborhood, a community report last October found that a still-growing number of residents were living in moldy apartments.

The highly publicized “toxic mold”—meaning the varieties that send mycotoxins into the air, the inhaling of which can acutely sicken anyone—causes most concern right after a flood. In the wake of Hurricane Matthew in South Carolina last year, sludge stood feet deep in homes for days. As it receded, toxic black mold grew. In one small community, Nichols, it was more the mold than the water itself that left the town’s 261 homes uninhabitable for months.

The more insidious and ubiquitous molds, though, produce no acutely dangerous mycotoxins but can still trigger inflammatory reactions, allergies, and asthma. The degree of impact from these exposure in New Orleans after Hurricane Katrina is still being studied.

Molds also emit volatile chemicals that some experts believe could affect the human nervous system. Among them is Joan Bennett, a distinguished professor of plant biology and pathology at Rutgers University, who has devoted her career to the study of fungal toxins. She was living in New Orleans during the storm, and she recalls that while some health experts were worried about heavy-metal poisoning or cholera, she was worried about fungus.

The smell of the fungi in her house got so strong after the flooding that it gave her headaches and made her nauseated. As she evacuated, wearing a mask and gloves, she took samples of the mold along with her valued possessions. Her lab at Rutgers went on to report that the volatile organic compounds emitted by the mold, known as mushroom alcohol, had some bizarre effects on fruit flies. For one, they affected genes involved in handling and transporting dopamine in a way that mimicked the pathology of Parkinson’s disease in humans. “More biologists ought to be looking at gas-phase compounds, because I’m quite certain we’ll find a lot of unexpected effects that we’ve been ignoring,” said Bennett.

 Mold in ceiling.  Credit: CDC

Tattoos are very popular these days, with about 29% of Americans having one or more. But there also is concern because so little is known about tattoo inks and any health effects on the body, and because adverse effects (e.g. inflammatory reactions) can occur months or years later. One study of 300 people in New York City with tattoos found that 10.3% reported experiencing an adverse tattoo reaction, of which 6% reported suffering from a chronic reaction from a specific color (especially red and black ink) that lasted for more than 4 months.

Now a new study in the journal Scientific Reports reports that microscopic particles from tattoo inks can migrate into the body and wind up in the lymph nodes of the immune system. Most tattoo inks contain particles of varying sizes - with some being very small nanoparticles. The researchers analyzed the skin and lymph nodes of 4 tattooed corpses and 2 corpses with no tattoos. They found the presence of several toxic elements such as nickel, chromium, cadmium, aluminum from the colorful tattoo inks. They found tattoo pigment particles in the skin, and that smaller ink nanoparticles had traveled to the lymph nodes - which leads to chronic enlargement of those lymph nodes, as well as lifelong exposure. From Science Daily:

Nanoparticles from tattoos travel inside the body, scientists find

The elements that make up the ink in tattoos travel inside the body in micro and nanoparticle forms and reach the lymph nodes according to a study published in Scientific Reports on 12 September by scientists from Germany and the ESRF, the European Synchrotron, Grenoble (France). 

The reality is that little is known about the potential impurities in the colour mixture applied to the skin. Most tattoo inks contain organic pigments, but also include preservatives and contaminants like nickel, chromium, manganese or cobalt. Besides carbon black, the second most common ingredient used in tattoo inks is titanium dioxide (TiO2), a white pigment usually applied to create certain shades when mixed with colorants. TiO2 is also commonly used in food additives, sun screens, paints. Delayed healing, along with skin elevation and itching, are often associated with white tattoos, and by consequence with the use of TiO2. 

"We already knew that pigments from tattoos would travel to the lymph nodes because of visual evidence: the lymph nodes become tinted with the colour of the tattoo. It is the response of the body to clean the site of entrance of the tattoo. What we didn't know is that they do it in a nano form, which implies that they may not have the same behaviour as the particles at a micro level. And that is the problem: we don't know how nanoparticles react," explains Bernhard Hesse, one of the two first authors of the study and ESRF visiting scientist.

X-ray fluorescence measurements on ID21 allowed the team to locate titanium dioxide at the micro and nano range in the skin and the lymphatic environment. They found a broad range of particles with up to several micrometres in size in human skin but only smaller (nano) particles transported to the lymph nodes. This may lead to the chronic enlargement of the lymph node and lifelong exposure [Original study.]

An opinion piece in a journal raises the question of whether having some parasites in the gut is beneficial. We tend to think of parasites as harmful (and yes, some parasite species cause tremendous human suffering and death), but some others seem to exist harmlessly in humans. I'm posting this article because the authors raise the question of whether with progress (sanitation, antibiotics, a Western diet, etc.) we have also lost something beneficial to humans - one-celled organisms (protozoa) that are parasites. They are found in people living in undeveloped countries, but people in developed countries have usually few or none.

Which leads to the question - is the loss of these parasites one of the reasons for the major increase in autoimmune disorders and such diseases as Crohn's disease and colitis? The answers to these questions are unknown at this time, so studies are needed. The authors point out that after millions of years of coevolution, the protists could be providing some beneficial effects to their human hosts - and that they may be part of a normal, healthy gut microbial community (microbiome).

As we know, studies show that in developed Western countries (as compared to undeveloped countries) there is lower microbial diversity in the gut - in other words, with industrialization comes lower bacterial diversity. But... higher microbial diversity is considered beneficial. Normally the human gut has hundreds of microbial species (bacteria, viruses, fungi) living in it and interacting. Some diseases or conditions result in alterations in these microbes, and even "microbial communities being out of whack" (dysbiosis).  The authors of the paper give examples of how the presence of certain non-pathogenic protozoan species in the gut is linked to higher gut microbial diversity and with the presence of bacteria that are anti-inflammatory and beneficial.

KEEP IN MIND: Gut protozoa are one-celled organisms (called protists) that live in the gut as parasites. Numerous protozoa can inhabit the gastrointestinal tract of humans.  According to a Tulane Univ. site "The majority of these protozoa are non-pathogenic commensals, or only result in mild disease", but some of these organisms can cause severe disease under certain conditions. [NOTE: commensal = characterized by a relationship in which one species is benefited while the other is unaffected]. In the following excerpts, a helminth refers to a parasitic worm, such as a fluke, tapeworm, or nematode.

Excerpts from Trends in Parasitology:  Gut Protozoa: Friends or Foes of the Human Gut Microbiota?

The importance of the gut microbiota for human health has sparked a strong interest in the study of the factors that shape its composition and diversity.... We argue that protozoa, like helminths, represent an important factor to take into account when studying the gut microbiome, and that their presence – especially considering their long coevolutionary history with humans – may be beneficial. From this perspective, we examine the relationship between the protozoa and their hosts, as well as their relevance for public health.

The human gut microbiota spans the tree of life and includes bacteria, viruses, and eukaryotes such as fungi, helminths, and protozoa. ...The observation that the gut bacterial microbiome is less diverse in populations from industrialized countries, compared to nonindustrialized countries, has been mostly explained by differences in dietary fiber intake, food sterilization, and the use of antibiotics. Here, we propose that the decreased prevalence of helminths and gut protozoa in industrialized countries is partly responsible for this loss of bacterial diversity.

We argue, based on the knowledge of helminths, that some intestinal protozoa might have beneficial effects on their host through their influence on the gut bacterial microbiome. The role of protozoa in shaping the gut microbiome of healthy individuals remains, however, largely unrecognized. The mechanisms through which protozoa influence the gut bacteria – and the consequences for human health of their absence in developed countries – are poorly understood and call for further attention. 

 The question is therefore whether gut eukaryotes are simply parasites that are detrimental to human health or whether, on the contrary, they could provide, after millions of years of coevolution, some beneficial effects to their hosts. Historically, protozoa and helminths have been considered parasites and assumed to have a detrimental effect on the host organism. Indeed, foodborne and waterborne parasitic diseases are important worldwide, resulting in considerable morbidity and mortality. However, while the focus remains on pathogens that have been investigated from a parasitological point of view, the eukaryotic residents of the gut are often commensal (i.e., benefiting from interacting with the host without affecting it) or even beneficial.

For example, even though some helminths can cause severe illness, infections are often asymptomatic, probably reflecting a long coevolutionary history (since at least 500 million years) and tolerance of these parasites by humans. Similarly, although the best-known protozoan microorganisms found in the human gut are pathogens (i.e., Cryptosporidium spp., Giardia intestinalis, Entamoeba histolytica), it is important to remember that many protozoa, in particular Blastocystis spp., can be found with high prevalence in healthy populations, and are common (and likely ancient) members of healthy microbiomes. Indeed, although protozoan cysts are not as resistant to decay as helminth eggs, they can be found in coprolites, confirming that protozoa, like helminths, were part of our ancestral gut community. 

Interestingly, recent findings also showed that the presence of commensal protozoa (Entamoeba spp. other than Entamoeba histolytica) was strongly associated with increased diversity and various shifts in composition of the gut bacterial microbiota in rural nonindustrialized populations. Higher diversity has also been found in subjects carrying Blastocystis spp., one of the few protozoa to be present at appreciable frequency in industrialized populations. These results suggest similarities between helminths and protozoa in their effect on the gut bacterial microbiome, and raise the possibility of a potentially beneficial effect of (some) protozoa on human health.

Here, we argue that some intestinal protozoan inhabitants could play an important, yet largely unrecognized, role in shaping the gut bacterial microbiota and in maintaining the host–microbe equilibrium, and they should be considered as ‘friends’ of the human gut.

Entamoeba coli - a non-pathogenic species that frequently lives as a commensal parasite in the human gastrointestinal tract. Credit: Wikipedia.

OK everyone - even if you sit all day at a desk job, the research is clear: try to get up and stretch or move a little every 30 minutes. Researchers followed middle-aged and older adults over a 5 1/2 year period and found that total sitting time (sedentary behavior) and prolonged, uninterrupted sedentary behavior were associated with in increased risk for death from any cause (all-cause mortality). But..adults who kept most of their sitting bouts to less than 30 minutes had the lowest risk of death. The researchers felt that getting up and moving every half hour seems to protect against the health risks (cardiometabolic effects) from just sitting and sitting and sitting. Are you moving yet?

From Science Daily: Long sitting periods may be just as harmful as daily total

A new study finds that it isn't just the amount of time spent sitting, but also the way in which sitting time is accumulated during the day, that can affect risk of early deathThe study, published online today in Annals of Internal Medicine, found that adults who sit for one to two hours at a time without moving have a higher mortality rate than adults who accrue the same amount of sedentary time in shorter bouts.

The researchers used hip-mounted activity monitors to objectively measure inactivity during waking time over a period of seven days in 7,985 black and white adults over age 45. (The participants were taking part in the REGARDS study, a national investigation of racial and regional disparities in stroke.)

On average, sedentary behavior accounted for 77 percent of the participants' waking hours, equivalent to more than 12 hours per day. Over a median follow-up period of four years, 340 of the participants died. Mortality risk was calculated for those with various amounts of total sedentary time and various sedentary patterns. Those with the greatest amount of sedentary time -- more than 13 hours per day -- and who frequently had sedentary bouts of at least 60 to 90 consecutive minutes had a nearly two-fold increase in death risk compared with those who had the least total sedentary time and the shortest sedentary bouts.

The researchers also found that participants who kept most of their sitting bouts to less than 30 minutes had the lowest risk of death. "So if you have a job or lifestyle where you have to sit for prolonged periods of time, we suggest taking a movement break every half hour. This one behavior change could reduce your risk of death, although we don't yet know precisely how much activity is optimal," Dr. Diaz said. [Original study.]

A major new report about colorectal cancer found that a number of lifestyle factors (diet, physical activity) increase or lower the risk of colorectal cancer. The report was an analysis of global research studies and was published by the American Institute for Cancer Research and World Cancer Research Fund.

They found that there is strong evidence that: being physically active, consuming whole grains, consuming foods containing dietary fiber, consuming dairy products, and taking calcium supplements all decrease the risk of colorectal cancer. On the other hand, there is strong evidence that: consuming red meat, consuming processed meat, consuming 2 or more alcoholic drinks per day, being overweight or obese, and being tall all increase the risk of colorectal cancer.

Also, that there is some evidence that: consuming foods containing vitamin C, consuming fish, vitamin D, consuming multivitamin supplements lower the risk of colorectal cancer. And there is some evidence that: low consumption on non-starch vegetables, low consumption of fruit, and consumption of foods containing haem iron might increase the risk of colorectal cancer. [NOTE: There are 2 types of iron in food: haem and non-haem iron. Haem iron is only found in meat, chicken, and fish, and is easily absorbed. Non-haem iron is found in plant foods, such as vegetables, cereals, beans, and lentils, but is not absorbed as well by the body.]

Finally, their cancer prevention recommendations for preventing cancer in general include: maintaining a healthy weight, being physically active and eating a healthy diet. (other posts on this - here, here, here). They also advise eating a healthy diet (think Mediterranean style diet) rather than relying on supplements to protect against cancer. The report also noted that inflammatory bowel disease and smoking increase the risk of colorectal cancer. From Science Daily:

Whole grains decrease colorectal cancer risk, processed meats increase the risk

Eating whole grains daily, such as brown rice or whole-wheat bread, reduces colorectal cancer risk, with the more you eat the lower the risk, finds a new report by the American Institute for Cancer Research (AICR) and the World Cancer Research Fund (WCRF). This is the first time AICR/WCRF research links whole grains independently to lower cancer riskDiet, Nutrition, Physical Activity and Colorectal Cancer also found that hot dogs, bacon and other processed meats consumed regularly increase the risk of this cancer. There was strong evidence that physical activity protects against colon cancer.

The new report evaluated the scientific research worldwide on how diet, weight and physical activity affect colorectal cancer risk. The report analyzed 99 studies, including data on 29 million people, of whom over a quarter of a million were diagnosed with colorectal cancer.

Other factors found to increase colorectal cancer include:  - Eating high amounts of red meat (above 500 grams cooked weight a week), such as beef or pork, - Being overweight or obese, - Consuming two or more daily alcoholic drinks (30 grams of alcohol), such as wine or beer. The report concluded that eating approximately three servings (90 grams) of whole grains daily reduces the risk of colorectal cancer by 17 percent. It adds to previous evidence showing that foods containing fiber decreases the risk of this cancer.

In the US, colorectal cancer is the third most common cancer among both men and women, with an estimated 371 cases diagnosed each day. AICR estimates that 47 percent of US colorectal cancer cases could be prevented each year through healthy lifestyle changes[The report.]

Another study finding that diet (what one eats) can work just as well as medications for a health condition - this time for one form of acid reflux disease. The researchers found that a Mediterranean style diet worked just as well as, and actually worked better, than medications for laryngopharyngeal reflux (LPR). They think these beneficial results will also work for gastroesophageal reflux disease (GERD). The plant-based Mediterranean diet (lots of fruits, vegetables, legumes, whole grains, seeds, nuts, olive oil, more fish and less meat) in the study has lots of other health benefits, while common medications (proton pump inhibitors - PPI) for reflux have many side effects, including very serious ones with prolonged use (stroke, heart attack, dementia, kidney damage).

It must be noted that the Mediterranean style diet group was also told to drink alkaline water, and both groups were told to follow "standard reflux precautions" (no coffee, tea, chocolate, soda, greasy, fried, fatty and spicy foods, and alcohol). However, the researchers point out that " prior studies have demonstrated little clinical change in reflux incidence with these lifestyle approaches" - meaning both groups in this study were told to follow standard reflux precautions, even though prior studies showed there was no benefit in doing so. (So why did they have the people follow them?)

Many studies have found numerous health benefits from a Mediterranean style diet, but it is unclear whether alkaline water has any health benefits, and the only study the researchers mention about alkaline water and GERD was done in laboratory tests (on cells), rather than in humans - so we really don't know (need studies!). Perhaps only a Mediterranean style diet is sufficient to treat acid reflux disease? Bottom line: dietary changes work best, benefits occur quickly (within a few weeks), and have many health benefits - therefore try them first in treating reflux symptoms. From Medical Xpress:

Mediterranean-style diet may eliminate need for reflux medications

A plant-based, Mediterranean-style diet has been shown to provide the same medical benefits for treating laryngopharyngeal reflux as popular reflux medications. .... When compared to patients who took the traditional reflux medication, proton pump inhibitors (PPI), those patients who consumed a 90-95% whole food, plant-based, Mediterranean-style diet paired with alkaline water had the same if not better reduction in reflux symptoms. 62.6 percent of patients treated with a plant-based diet and alkaline water saw a six point reduction in their Reflux Symptom Index (RSI - a measurement for the severity of reflux symptoms), compared to 54.1 percent reduction in patients taking PPI's.

Though this research only focused on those with laryngopharyngeal reflux, this same diet regimen has implications to help patients with gastro-esophageal acid reflux (also known as GERD). Lead author of the study, Craig H. Zalvan, MD, FACS, chief of Otolaryngology and medical director of The Institute for Voice and Swallowing Disorders at Northwell Health's Phelps Hospital and researcher at the Feinstein Institute, said he was formerly one of the largest prescribers of PPI's in the region. Feeling that there had to be a better approach to treating reflux conditions like laryngopharyngeal reflux, he started to research alternatives. "Although effective in some patients, I felt medication couldn't be the only method to treat reflux and recent studies reporting increased rates of stroke and heart attack, dementia and kidney damage from prolonged PPI use made me more certain," said Dr. Zalvan. 

The diet suggested by Dr. Zalvan consists of mostly fruits, vegetables, grains and nuts with near complete cessation of dairy and meats including beef, chicken, fish, eggs and pork. This is in addition to standard reflux diet precautions like avoiding coffee, tea, chocolate, soda, greasy and fried food, spicy foods, fatty foods and alcohol. Along with relieving reflux symptoms, Dr. Zalvan noted that many of his patients who were treated with a plant-based diet also experienced some weight loss and a reduction of symptoms and medication use from other medical conditions like high blood pressure and high cholesterol. Dr. Zalvan said that a plant-based diet approach with alkaline water and standard reflux precautions should either be attempted prior to the use of medication or with the short-term use of medication for more severe needs. [Original study.]

For years medicine has viewed cancer as a "malignant seed" and looked for ways to kill these seeds before they spread throughout the body (metastasis). This past week two provocative articles stresses that we should also look at the "environments" that the cancer cells grow in - that some environments in the person nourish and encourage the growth of cancer, while other environments suppress the growth of cancer and don't allow its spread.

This is a very different approach to cancer, but it also makes sense. Studies find that small cancers can just sit there harmlessly or regress on their own - even breast and prostate cancers, but it raises the questions: Why? Why do they regress or are suppressed in some people, but grow malignantly in others? What is different about those people and their bodies?

Researchers are starting to do research along these lines - that is, looking at the environment that cancer may or may not grow in. Yesterday's post discussed amazing research showing that cancer tumors are continuously shedding cancer cells in a person's body, but only in some people do they actually take root and grow. It's as if some people have environments that encourage growth of cancer, while other people have environments that do not.

Today's article, besides discussing the micro-environment in which cancer grows, also discusses the role of inflammation in cancer and how things causing inflammation (e.g., smoking, inactivity, poor diet) are also associated with cancer. So some micro-environments are good for cancer, and some are not. Some of the research I've posted in the past has tried to see if influencing the person's environment with "lots of exercise and activity"(here and here), or vitamin D levels in the body, or a person's diet somehow prevents or keeps cancer in check. From Nautilus:

The Problem with the Mutation-Centric View of Cancer

To better understand and treat cancer, physicians need to stop oversimplifying its causes. Cancer results not solely from genetic mutations but by adapting to and thriving in micro-environments in the body. That’s the point of view of James DeGregori, a professor in the Department of Biochemistry and Molecular Genetics at the University of Colorado School of Medicine.... In our conversation, DeGregori expanded on how a renewed focus on micro-environments and Darwinian evolutionary pressures can benefit cancer research.

How should we study the origins of cancer? My lab has been researching the origins of cancers for the last 15 to 17 years. We’re trying to understand cancer from an evolutionary viewpoint, understanding how it evolves. A lot of people think about cancer from an evolutionary viewpoint. But what sets us apart is that we’ve really come to understand cancer by the context these cells find themselves in.

What’s an example of such a context? While other people will think about aging as the time for mutations to cause advantageous events [for cancer] in cells, we see aging as a very different process. It’s not about the time you get mutations—you get many mutations when you’re young. It’s the tissue environment for the cells that changes dramatically as we age. Those new tissue environments basically stimulate the evolution. So the evolution isn’t a process that’s limited by the mutation so much as a process that is limited by micro-environment changes.

Instead of just attacking the cancer, we should be altering the micro-environment to disfavor the cancer. What we’ve shown is that you could take the same oncogenic mutation and put it into young cells in a young environment and it’s not advantageous [for cancer]. It doesn’t cause expansions and it doesn’t cause the cancer. You make that same mutation in old tissue and it can be adaptive for cancer.

When we’re young, our tissues are relatively constant and well maintained. If you look at the tissues of a 20-year-old and a 35-year-old, or maybe even a 40-year-old, you wouldn’t notice much of a difference. It’s not like we age linearly. It’s only after 45 or 50 that we start to really go downhill. Then that downhill accelerates. As those changes happen, our tissues are no longer presenting that same environment to our cells. What I argue is that we evolve stem cells, or the cells that are continuously making our tissues, to be well adapted to the youthful environment and not to be well adapted to an aged environment.

I’ve been criticized as putting forward a straw man because, essentially, they don’t really talk about micro-environment. But to me that’s the whole point—there’s a major factor that should be considered, and I would say not just “should.” You can’t really model cancer without it and yet they’re not taking it into account. In other words, the difference between a smoker and a nonsmoker isn’t just that the smoker has more mutations. The difference is the smoker’s lung—and I’m sure you’ve seen pictures of the charred blackened lungs of a smoker—and that presents a completely different environment for cells with mutations.

How can your ideas change the way doctors treat cancer? Mostly we now target the cancer cells. That’s changing somewhat. Immune therapies are in some ways targeting the environment. It’s almost like a predator strategy. Instead of just attacking the cancer, we should be altering the micro-environment to disfavor the cancer. If you just attack the cancer, you immediately select for resistance, which is what they see in the clinic so often. You can get a person into remission, but it’s keeping them in remission that’s the hard part. Cancer that comes back is inevitably worse than the cancer you started with.

.... If we can understand what factor about a smoker’s lung, or an old person’s lung, leads to more cancer, then we could modulate that factor to basically prevent the cancers from occurring in the first place. If it’s inflammation, for all we know maybe there are even dietary interventions that will reduce inflammation in the lungs. All the things we know that are associated with cancer are also associated with increased inflammation. Everything we know that basically leads to longer, healthier lives, is known to modulate inflammation. Exercise reduces it. Good diet reduces it. Not smoking, not exposing yourself to too much sun.

 Cancer cells. Credit:Wikipedia, National Cancer Institute