The Global Fool

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Food Additives, Microbiota, and Inflammation
Mar27

Food Additives, Microbiota, and Inflammation

By Roberta Attanasio “For centuries, additives have served useful functions in a variety of foods. Our ancestors used salt to preserve meats and fish, added herbs and spices to improve the flavor of foods, preserved fruit with sugar, and pickled cucumbers in a vinegar solution. Today, consumers demand and enjoy a food supply that is flavorful, nutritious, safe, convenient, colorful and affordable. Food additives and advances in technology help make that possible.” But, are food additives safe? Results from a recent study show that some food additives known as emulsifiers can alter the composition and location of the gut microbiota — the diverse population of 100 trillion bacteria that inhabit the intestinal tract — thus inducing intestinal inflammation. This inflammation, in turn, promotes the development of inflammatory bowel disease (Crohn’s disease and ulcerative colitis) and metabolic syndrome — disorders that are often severe and debilitating and afflict millions of people. The ancient Greeks used the emulsifying power of beeswax in cosmetic products. Egg yolk was probably the first emulsifier ever used in food production back in the early 19th century. Emulsifiers are now added to bread, chocolate, ice cream, margarine, processed meat, and more. But why? Add oil to water and the two liquids will never mix. At least not until an emulsifier is added. Emulsifiers are molecules with one water-loving (hydrophilic) and one oil-loving (hydrophobic) end. They make it possible for water and oil to become finely dispersed in each other, creating a stable, homogenous, smooth emulsion. The study results show that, in a mouse model, two common emulsifiers — caboxymethylcellulose (CMC) and polysorbate-80 (P80) — not only change the composition of the gut microbiota, they also make the gut more porous. The altered microbiota has enhanced capacity to digest and infiltrate the dense mucus layer that lines the intestine — bacteria reach immune cells, thus inducing activation of inflammatory pathways and the development of severe inflammation. Such changes in bacteria trigger chronic colitis in mice genetically prone to this disorder, due to abnormal immune systems. In contrast, in mice with normal immune systems, emulsifiers induce low-grade or mild intestinal inflammation and metabolic syndrome, characterized by increased levels of food consumption, obesity, hyperglycemia and insulin resistance. Fergus Shanahan (University College Cork), who was not involved in the study, told Ed Yong: “This work cannot be ignored.” He doubted that most people would be significantly affected by occasionally eating foods with emulsifiers — but risk might change for those who have a genetic predisposition to inflammatory bowel disease, or who eat lots of processed foods. Andrew Gewirtz, senior author of the study, said in a press release: “We do...

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Small Predator Diversity Plays a Significant Role in the Spread of Infectious Diseases
Mar23

Small Predator Diversity Plays a Significant Role in the Spread of Infectious Diseases

By Roberta Attanasio Biodiversity is a term coined to describe the diversity of all living things, from human beings to microorganisms. A New York Times editorial published almost two decades ago aptly describes the importance of the biodiversity concept: “Biodiversity is a hugely important concept that stresses the coherence and interdependence of all forms of life on earth and a new willingness to appraise the meaning of that interdependence, not just for humans but for every one of life’s component parts.” The editorial goes on to illustrate the alarming effects of biodiversity loss: “Biodiversity is a way of talking about what scientists have long understood and a way of reminding the rest of us of a cardinal fact: that we are standing in the midst of the earth’s sixth great extinction of diverse species, that this extinction is driven by us and that we are not now and will never be immune to its effects.” One of these effects is the worldwide spike in infectious diseases, as suggested by a study recently published in the journal Proceedings of the National Academy of Sciences. The study (Predator diversity, intraguild predation, and indirect effects drive parasite transmission) explores how the diversity of small predators shapes the transmission of parasites in wetlands. Lead author Jason Rohr said in a press release by Penn State: “In the last century, there has been an unprecedented global increase in infectious diseases and a concomitant decline in and homogenization of biodiversity. The controversial ‘dilution effect hypothesis’ suggests that the two phenomena might be linked, or that biodiversity often decreases disease risk.” The study, which included a series of laboratory experiments, field surveys and mathematical modeling, shows that — in presence of various species of dragonfly larvae — there is a reduction of frog infections caused by trematodes, which are parasitic flatworms also known as flukes. The dragonfly larvae are small predators that eat trematodes. Val Beasley, senior author of the study, said in the press release that various species of trematodes penetrate tadpoles. The trematodes sometimes kill the tadpoles. In other instances, the trematodes weaken them by causing tissue damage, kidney failure, or severe limb deformities while the tadpoles develop into frogs. He added that other vertebrate species commonly catch trematode infections from bodies of water. These vertebrate species include wildlife, domestic animals and humans — mostly children — who are commonly affected by schistosomiasis in tropical parts of the world. Schistosomiasis is a parasitic disease carried by freshwater snails infected with one of the five varieties of the parasite Schistosoma, a type of trematode. Although the worms that cause schistosomiasis are not found in the...

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TB Unmasked: Healthcare Workers and the Global Tuberculosis Epidemic
Mar21

TB Unmasked: Healthcare Workers and the Global Tuberculosis Epidemic

By Roberta Attanasio World TB Day, falling on March 24th each year, is approaching — it reminds us that tuberculosis (TB) is a massive global health problem. Indeed, according to the World Health Organization (WHO), tuberculosis is one of the world’s deadliest communicable diseases. It is second only to HIV/AIDS as the greatest killer worldwide due to a single infectious agent. In 2013, an estimated 9.0 million people developed TB and 1.5 million died from it — mostly in developing countries. However, TB is curable and preventable. The WHO estimates that 37 million lives were saved between 2000 and 2013 through effective diagnosis and treatment. Despite the many saved lives, the death toll is still unacceptably high. Last month, Anthony S. Fauci, Director of National Institute of Allergy and Infectious Diseases, said: “Progress is being made in the international fight against TB; however, the disease remains entrenched in many countries, especially those in Sub-Saharan Africa.”   TB is caused by bacteria (Mycobacterium tuberculosis) that most often affect the lungs. It spreads from person to person through the air. When people with lung TB cough, sneeze or spit, they propel the TB bacteria into the air. A person needs to inhale only a few of these bacteria to become infected. About one-third of the world’s population has latent TB — people have been infected by TB bacteria but are not (yet) ill with the disease and cannot spread the bacteria. When a person develops active TB (disease), the symptoms (cough, fever, night sweats, weight loss and others) may be mild for many months. For this reason, people with active TB may delay seeking care, and bacteria can spread to others. People ill with TB can infect up to 10-15 other people through close contact over the course of a year. Without proper treatment, up to two thirds of people ill with TB will die. Unfortunately, the vaccine currently available to prevent TB has limited efficacy. Healthcare workers who come into contact with patients affected by active TB are at considerable risk of contracting the disease. Indeed, every day, millions of healthcare workers around the world put their lives at risk as they combat tuberculosis. They’re vulnerable to TB exposure and infection. And they deserve to be protected. Therefore, Aeras — a nonprofit biotech advancing the development of new tuberculosis vaccines for the world — launched the TB UNMASKED campaign on September 24, 2014. TB UNMASKED supports and empowers people who put themselves at risk of tuberculosis infection through caring for patients, and gives healthcare workers on the front lines of the TB epidemic the opportunity to tell their stories using photographs,...

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Early Menopause: Links to Ubiquitous Endocrine-Disrupting Chemicals
Feb23

Early Menopause: Links to Ubiquitous Endocrine-Disrupting Chemicals

By Roberta Attanasio There are as many endocrine-disrupting chemicals (also called endocrine disruptors) as there are deleterious health effects caused by them. These chemicals mimic the body’s hormones and confuse our physiological systems — we respond to them with a series of inappropriate changes that, depending on the specific endocrine disruptor, lead to the development of obesity, cancer, malformation of sex organs, and more. They are pervasive in the environment — they’re found in the soil, air and water throughout the world — and many persist for long periods of time. Thus, it’s not surprising that, in 2013, the impact of endocrine disruptors on human health was defined as a “global threat” by a group of experts convened by the United Nations Environment Programme and the World Health Organization.   Phthalates are some of the most studied endocrine disruptors. They’re used to make plastic more flexible and cosmetics smoother. Phthalate use in children’s toys was banned in 2008. However, results from a recent study show that high amounts of certain phthalates are present in some meats, cooking oils and dairy products, thus contributing to children exposure despite the ban. In her article “A threat to male fertility“, Deborah Blum writes: “A growing body of work over the last two decades suggests that phthalates can rewire the male reproductive system, interfering with the operation of androgenic hormones, such as testosterone, that play key roles in male development. That mechanism, some experts believe, explains findings that link phthalate exposure to changes in everything from testicular development to sperm quality.” In addition, according to results from a new study, two phthalates belong to a group of 15 chemicals that are significantly associated with early menopause and may have detrimental effects on ovarian function. Earlier menopause and decline in ovarian function may adversely affect fertility and lead to earlier development of heart disease and osteoporosis. The other chemicals are nine polychlorinated biphenyls, three pesticides, and a furan. Women that have high levels of these chemicals in their bodies experience menopause two to four years earlier than women with lower levels of these chemicals. For the study, the researchers analyzed data collected from 1999-2008 as part of the National Health and Nutrition Examination Survey, conducted by the U.S. Centers for Disease Control and Prevention. The survey incrporated data from 31,575 people, including 1,442 menopausal women who had been tested for presence of endocrine-disrupting chemicals in their blood and urines. It was designed so that the women who had undergone chemical testing would represent a population of almost 9 million menopausal women. The strongest association with early menopause was found for mono-(2-ethyl-5-hydroxyhexyl) phthalate and mono-(2-ethyl-5-oxohexyl) phthalate,...

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E-Cigarettes and Vaping May Cause Lung Damage and Impaired Immune Responses
Feb14

E-Cigarettes and Vaping May Cause Lung Damage and Impaired Immune Responses

By Roberta Attanasio A few months ago, Oxford Dictionaries announced “vape” as its international Word of the Year 2014 – language research conducted by their editors revealed that its use in 2014 had more than doubled compared to 2013 (and increased by 30-fold since 2012), mostly because of the rapidly growing popularity of electronic cigarettes and the expanding debate over their safety. Although e-cigarettes are portrayed as devices that can help adult smokers quit while providing a safe alternative to tobacco smoking, mounting evidence shows that these devices may cause considerable harm. Indeed, about two weeks ago, California health officials said that e-cigarettes represent a rising public-health risk that threaten to unravel progress made on tobacco by “re-normalizing smoking behavior” and luring a new generation into nicotine addiction. Electronic cigarettes, or e-cigarettes, are tobacco-free and vaporize liquid (also called e-liquid or e-juice) that contains nicotine, producing “faux” smoke or vapor. Because they don’t burn anything, e-cigarettes don’t release any smoke – therefore, users don’t “smoke”, they “vape.” In addition to nicotine, the e-juice typically contains vegetable glycerin, propylene glycol, and flavorings. There are several types of e-juices, each containing different flavorings – these flavorings make “vaping” especially appealing to young smokers who would not normally try tobacco. While nicotine addiction caused by vaping in young smokers is clearly a major public health issue, there are also public health concerns associated with toxic substances released by e-cigarette vapors. Indeed, e-cigarettes may likely become a toxic replacement for tobacco products. Results from a recent study (published in the scientific journal PLOSone) show that emissions from e-cigarettes damage lung cells. The damage is mostly caused by inflammatory responses and oxidative stress, which are known to represent key events in the development of chronic airway diseases. Some flavored e-juices – particularly those containing cinnamon – are more toxic than others. Irfan Rahman, lead author of the study, said in a press release: “Several leading medical groups, organizations, and scientists are concerned about the lack of restrictions and regulations for e-cigarettes. Our research affirms that e-cigarettes may pose significant health risks and should be investigated further. It seems that every day a new e-cigarette product is launched without knowing the harmful health effects of these products.” Results from an additional study recently published in the same journal confirm that vaping may cause potential deleterious health effects. Using a mouse model, the researchers showed that e-cigarettes compromise the immune system in the lungs and generate some of the same potentially dangerous chemicals found in traditional nicotine cigarettes. Thomas Sussan, lead author of this study, said in a press release: “E-cigarette vapor alone produced mild effects...

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