Chapter 13. Homeostasis: Active Regulation of the Internal Environment

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/ By Elizabeth Preston On the first page of Heinz Koop’s fecal analysis test results, a bar showed where he fell on a gradient from green to red. A label above said, in German: “Overall dysbiosis.” Koop was not in the green or even the yellow regions, but a worrisome orange. It was a bad result — but, he says, “I was kind of happy.” Doctors hadn’t given him a satisfying answer about his recurring bloody diarrhea and other gut troubles. But Koop had learned on Facebook that he could test his gut microbiome — the community of bacteria and other organisms living in his gastrointestinal tract — to look for problems. Koop ordered a test from a German laboratory called Medivere. The results said his gut microbes were imbalanced, which was something he thought he could treat. Soon he would be attempting to correct this imbalance by chauffering a friend’s fresh stool samples home to implant up his own colon. Trillions of microbes living on and in our bodies, especially our guts, make up our microbiome. The bugs in our bowel are not just there to slow down our poop, as one researcher speculated in 1970, but are intricately connected to our health. Gut microbes help us digest our food, make critical vitamins, and keep pathogens out. Over the past decade or so, research into the microbiome has exploded as researchers have tried to tease apart the complex connections between our diseases and our resident microbes. Today, at least 10 percent of published microbiome papers use the term dysbiosis to describe changes in the microbiome, estimates Katarzyna Hooks, a computational biologist now at Evotec, a global biotechnology company headquartered in Germany. Some scientists say the term is useful for communicating a specific finding, though they acknowledge its limitations. Other scientists hate it. Copyright 2019 Undark

Keyword: Obesity
Link ID: 26729 - Posted: 10.22.2019

Jon Hamilton Brain scientists are offering a new reason to control blood sugar levels: It might help lower your risk of developing Alzheimer's disease. "There's many reasons to get [blood sugar] under control," says David Holtzman, chairman of neurology at Washington University in St. Louis. "But this is certainly one." Holtzman moderated a panel Sunday at the Society for Neuroscience meeting in Chicago that featured new research exploring the links between Alzheimer's and diabetes. "The risk for dementia is elevated about twofold in people who have diabetes or metabolic syndrome (a group of risk factors that often precedes diabetes)," Holtzman says. "But what's not been clear is, what's the connection?" One possibility involves the way the brain metabolizes sugar, says Liqin Zhao, an associate professor in the school of pharmacy at the University of Kansas. Zhao wanted to know why people whose bodies produce a protein called ApoE2 are less likely to get Alzheimer's. Previous research has shown that these people are less likely to develop the sticky plaques in the brain associated with the disease. But Zhao looked at how ApoE2 affects glycolysis, a part of the process that allows brain cells to turn sugar into energy. So she gave ApoE2 to mice that develop a form of Alzheimer's. And sure enough, Zhao says, the substance not only improved energy production in brain cells but made the cells healthier overall. "All of this together increased the brain's resilience against Alzheimer's disease," she says. © 2019 npr

Keyword: Alzheimers; Obesity
Link ID: 26728 - Posted: 10.22.2019

Fatty tissue has been found in the lungs of overweight and obese people for the first time. Australian researchers analysed lung samples from 52 people and found the amount of fat increased in line with body mass index. They said their findings could explain why being overweight or obese increased asthma risk. Lung experts said it would be interesting to see if the effect could be reversed by weight loss. In the study, published in the European Respiratory Journal, scientists looked at post-mortem samples of lung donated for research. Fifteen had had no reported asthma, 21 had asthma but died of other causes and 16 died of the condition. The scientists used dyes to carry out detailed analyses of almost 1,400 airways from the lung samples under the microscope. The researchers found adipose (fatty) tissue in the walls of airways, with more present in people with a higher body mass index, And they say the increase in fat appears to alter the normal structure of the airways and cause inflammation in the lungs - which could explain the increased risk of asthma in overweight or obese people. Dr Peter Noble, an associate professor at the University of Western Australia, in Perth who worked on the study, said: "Being overweight or obese has already been linked to having asthma or having worse asthma symptoms. "Researchers have suggested that the link might be explained by the direct pressure of excess weight on the lungs or by a general increase in inflammation created by excess weight." But, he said, their study suggested "another mechanism is also at play". © 2019 BBC.

Keyword: Obesity
Link ID: 26722 - Posted: 10.19.2019

Jules Montague In a dark, nondescript room tucked away in the depths of a London research centre, Lucy Gallop is demonstrating how we might treat eating disorders in future. Improbably, she presses on a pedal under a desk, like a driver pulling away in first gear. Magnetic pulses pass through an electromagnetic coil which is held to a patient’s head. Clicking sounds fill the room and the patient’s neural activity is temporarily altered over the course of a few minutes. A brain scan is visible to her right, the target area already visualised. “The neuronavigation tells you whether or not you’re at the right place,” Gallop says of the process, known as repetitive transcranial magnetic stimulation (rTMS). “It’s replicable so you know when the participants come in the next time, you’re stimulating the same area.” Gallop’s work carries deep personal significance: “My sister had anorexia so I was exposed to family therapy from a young age. And truthfully, it really exposed me to how treatment is very difficult – making a full recovery from anorexia is very difficult.” New treatment innovations are urgently needed for eating disorders, which affect an estimated 1.25 million people in the UK. Hospital admissions have almost doubled in the last six years and patients are sent hundreds of miles away from home for treatment. Earlier this month, new figures showed that one in six consultant posts in eating disorder services are vacant. Patients with eating disorders are twice as likely to die prematurely than the general population. © 2019 Guardian News & Media Limited

Keyword: Anorexia & Bulimia
Link ID: 26719 - Posted: 10.18.2019

Tim McDonnell High rates of childhood obesity are a problem in a rising number of low- and middle-income countries, according to a new global assessment of child malnutrition by UNICEF. It's the agency's most comprehensive nutrition report in two decades. The report paints a complex, dire picture of the state of children's health. Overall, it found that around 200 million children under age 5, or 1 in 3 worldwide, are either undernourished or overweight. Wasting (below-average weight for height) and micronutrient deficiency remain persistent challenges in Africa and South Asia. Still, there's some good news: Stunting (below-average height for age) has dropped sharply in the last two decades on every continent except Africa. Meanwhile, at least 340 million adolescents worldwide between ages 5-19, and 40 million children under age 5, have been classified as overweight, the report found. The most profound increase has been in the 5-19 age group, where the global rate of overweight increased from 10.3% in 2000 to 18.4% in 2018. "It's a shockingly fast increase," says Laurence Chandy, director of UNICEF's Office of Global Insights and Policy and a lead author of the report. "It's hard to think of any development indicator where you see such a rapid deterioration." Most of those children live in high- and middle-income countries in North America, Eastern Europe, Pacific island nations and the Middle East. The U.S. is near the top of the list, with a rate of adolescent overweight around 42% (the highest rates, up to 65% are in Palau, Nauru and other in Pacific island nations, which have long struggled with obesity driven by a heavy reliance on imported food). © 2019 npr

Keyword: Obesity
Link ID: 26717 - Posted: 10.18.2019

By Aaron E. Carroll There’s a decent chance you’ll be reading about diet soda studies until the day you die. (The odds are exceedingly good it won’t be the soda that kills you.) The latest batch of news reports came last month, based on another study linking diet soda to an increased risk of death. As usual, the study (and some of the articles) lacked some important context and caused more worry than was warranted. There are specific reasons that this cycle is unlikely to end. 1. If it’s artificial, it must be bad. People suspect, and not always incorrectly, that putting things created in a lab into their bodies cannot be good. People worry about genetically modified organisms, and monosodium glutamate and, yes, artificial sweeteners because they sound scary. But everything is a chemical, including dihydrogen monoxide (that’s another way of saying water). These are just words we use to describe ingredients. Some ingredients occur naturally, and some are coaxed into existence. That doesn’t inherently make one better than another. In fact, I’ve argued that research supports consuming artificial sweeteners over added sugars. (The latest study concludes the opposite.) 2. Soda is an easy target In a health-conscious era, soda has become almost stigmatized in some circles (and sales have fallen as a result). It’s true that no one “needs” soda. There are a million varieties, and almost none taste like anything in nature. Some, like Dr Pepper, defy description. But there are many things we eat and drink that we don’t “need.” We don’t need ice cream or pie, but for a lot of people, life would be less enjoyable without those things. None of this should be taken as a license to drink cases of soda a week. A lack of evidence of danger at normal amounts doesn’t mean that consuming any one thing is huge amounts is a good idea. Moderation still matters. © 2019 The New York Times Company

Keyword: Obesity
Link ID: 26696 - Posted: 10.14.2019

Allison Aubrey There's fresh evidence that eating a healthy diet, one that includes plenty of fruits and vegetables and limits highly processed foods, can help reduce symptoms of depression. A randomized controlled trial published in the journal PLOS ONE finds that symptoms of depression dropped significantly among a group of young adults after they followed a Mediterranean-style pattern of eating for three weeks. Participants saw their depression "score" fall from the "moderate" range down to the "normal" range, and they reported lower levels of anxiety and stress too. Alternatively, the depression scores among the control group of participants — who didn't change their diets — didn't budge. These participants continued to eat a diet higher in refined carbohydrates, processed foods and sugary foods and beverages. Their depression scores remained in the "moderate severity" range. "We were quite surprised by the findings," researcher Heather Francis, a lecturer in clinical neuropsychology at Macquarie University in Sydney, Australia, told NPR via email. "I think the next step is to demonstrate the physiological mechanism underlying how diet can improve depression symptoms," Francis said. In this study, participants in the "healthy eating" arm of the study ate about six more servings of fruits and vegetables per week, compared with the control group. Participants "who had a greater increase in fruit and vegetable intake showed the greatest improvement in depression symptoms," Francis said. © 2019 npr

Keyword: Depression; Obesity
Link ID: 26693 - Posted: 10.11.2019

By Eva Frederick As the weather cools, one species of squirrel in the U.S. Midwest is gearing up for one of the most intense naps in the animal kingdom. For up to 8 months, the tiny mammals won’t eat or drink anything at all—and now scientists know how they do it. Most squirrels don’t hibernate—instead, they stash food for the cold season and spend the winter snug in their nests. Not the 13-lined ground squirrel (Ictidomys tridecemlineatus), whose heart rate, metabolism, and body temperature dramatically plummet during their long rest—similar to bears, woodchucks, and other hibernating animals. To find out how the squirrels suppress their thirst—a powerful force that could potentially wake them up—researchers measured the blood fluid, or serum, of dozens of squirrels, divided into three groups: those that were still active, those that were in a sleep-of-the-dead hibernation state called torpor, and those that were still hibernating, but in a drowsy in-between state. Generally, a high serum concentration makes animals, including humans, feel thirsty. The sleeping squirrels’ serum concentration was low, preventing them from waking up for a drink. Even when researchers roused the torpid squirrels, they wouldn’t drink a drop—until the team artificially increased the concentration of their blood serum. Next, the researchers wanted to know how the squirrels’ blood concentration dropped so low. Perhaps the squirrels drank a lot of water prehibernation to dilute their blood, the researchers thought. But when they filmed squirrels preparing for their winter snooze, they found the animals actually drank less water than they normally did. © 2019 American Association for the Advancement of Science

Keyword: Sleep
Link ID: 26661 - Posted: 10.02.2019

By Tina Hesman Saey Mice (and maybe people) may metabolize food according to daily, circadian rhythms set by gut bacteria. Microbes in the small intestine of mice rhythmically dictate when fat is taken up by cells that line the organ, researchers report. The study, described in the Sept. 27 Science, details how gut microbes influence a host’s metabolism. If the findings carry over to people, the research may give clues to why jet lag and night-shift work, which can throw off circadian rhythms, often lead to obesity, diabetes and other health problems. Researchers knew that human cells have molecular clocks that time 24-hour circadian cycles of metabolism (SN: 11/8/18), and that gut microbes in the colon follow their hosts’ biological beat (SN: 10/16/14). But the new study finds that, at least in the small intestine, microbes can set rhythms for host cells to follow. That work was done in mice, but the process may work similarly in people. The new research “is helping us appreciate just how intertwined are the metabolisms of the microbiota and their mammalian hosts,” says microbiologist and immunologist Andrew Gewirtz of Georgia State University in Atlanta who was not involved in the work. “It’s a very intimate interaction, regulating things as basic as circadian rhythms, which was quite a surprise.” © Society for Science & the Public 2000–2019.

Keyword: Biological Rhythms
Link ID: 26651 - Posted: 09.27.2019

Obesity is not a choice and making people feel ashamed results only in them feeling worse about themselves, a report by top psychologists says. It calls for changes in language to reduce stigma, such as saying "a person with obesity" rather than an "obese person". And it says health professionals should be trained to talk about weight loss in a more supportive way. A cancer charity's recent ad campaign was criticised for "fat shaming". Obesity levels rose by 18% in England between 2005 and 2017 and by similar amounts in Scotland, Wales and Northern Ireland. This means just over one in four UK adults is obese while nearly two-thirds are overweight or obese. But these increases cannot be explained by a sudden loss of motivation across the UK - it is a lot more complicated than that, according to the British Psychological Society report, which concludes it "is not simply down to an individual's lack of willpower". "The people who are most likely to be an unhealthy weight are those who have a high genetic risk of developing obesity and whose lives are also shaped by work, school and social environments that promote overeating and inactivity," it says. "People who live in deprived areas often experience high levels of stress, including major life challenges and trauma, often their neighbourhoods offer few opportunities and incentives for physical activity and options for accessing affordable healthy food are limited." Psychological experiences also play a big role, the report says, with up to half of adults attending specialist obesity services having experienced difficulties in childhood. And stress caused by fat shaming - being made to feel bad about one's weight - by public health campaigns, GPs, nurses and policymakers, often leads to increased eating and more weight gain. © 2019 BBC

Keyword: Obesity
Link ID: 26640 - Posted: 09.24.2019

A landmark French trial is due to begin to decide whether a diabetes pill prescribed for weight loss was behind the deaths of up to 2,000 people. Servier, the drug's manufacturer, is accused of deceiving users over the killer side effects of a drug later used to treat overweight diabetics. Believed to be one of France's biggest healthcare scandals, the firm is on trial for manslaughter and deceit. Servier has denied the charges, saying it did not lie about the side effects. French health experts believe the drug known as Mediator could have killed anywhere between 500 and 2,000 people before it was finally taken off the market in 2009. The country's state drug regulator, accused of not acting to prevent deaths and injuries, is also on trial. The trial will involve more than 2,600 plaintiffs and 21 defendants, and is expected to run over the course of six months. It will also look into why the drug, which was introduced in 1976, was allowed to sell for so long despite various warnings. Lawyers representing the plaintiffs argue that the drug manufacturer purposely misled patients for decades, and that this was bolstered by lenient authorities. Servier has been accused of profiting at least €1bn ($1.1bn, £880m) from the drug's sales. "The trial comes as huge relief. Finally, we are to see the end of an intolerable scandal," Dr Irene Frachon, a pulmonologist credited with lifting the lid on the side effects, told Reuters news agency. Dr Frachon's research drew on medical records across France and concluded that there was a clear pattern of heart valve problems among Mediator users. This prompted many more studies which ultimately led to the drug's ban. One study concluded that 500 deaths could be linked to Mediator between 1976 and 2009. A second one put the figure at 2,000. Those numbers have been disputed by Servier, which has said that there are only three documented cases where death can be clearly attributed to the use of Mediator. In other cases, it says, aggravating factors were at work. © 2019 BBC

Keyword: Obesity
Link ID: 26639 - Posted: 09.24.2019

By Perri Klass, M.D. Cesarean delivery can save a baby — or a mother — at a moment of medical danger. However, cesarean births have been linked to an increased risk of various long-term health issues for both women and children, and a recent study shows an association between cesarean birth and the risk of developing autism or attention deficit disorder. The study, published in August in JAMA Network Open, was a meta-analysis. It looked at data from 61 previously published studies, which together included more than 20 million deliveries, and found that birth by cesarean section was associated with a 33 percent higher risk of autism and a 17 percent higher risk of attention deficit disorder. The increased risk was present for both planned and unplanned cesarean deliveries. The first and most important thing to say is that these were observational studies, and that association is not the same as causation. The children born by cesarean section may be different in important ways from the children born vaginally, and those differences may include factors that could affect their later neurodevelopment, from maternal health issues to developmental problems already present during pregnancy to prematurity to difficult deliveries. If your child was born by cesarean section, there’s nothing you can do to change that, and knowing about this association may make you worry, while if you’re pregnant it may make you even more anxious about how the delivery will go. But the information about long-term associations and mode of birth should help to drive further research and understanding of how and why these associations play out. Tianyang Zhang, a Ph.D. student in clinical neuroscience at the Karolinska Institute in Stockholm who was the first author on the article, said that earlier research had shown various associations between cesarean delivery and long-term health problems, including higher rates of obesity and asthma in children. This study looked at a range of developmental and mental health issues. Though it did find an association between cesarean delivery and autism spectrum and attention deficit disorders, it did not find significant associations with others, such as tic disorders, obsessive-compulsive disorders or eating disorders. © 2019 The New York Times Company

Keyword: Autism; ADHD
Link ID: 26638 - Posted: 09.23.2019

By James Gallagher Health and science correspondent, BBC News Babies born by Caesarean section have dramatically different gut bacteria to those born vaginally, according to the largest study in the field. The UK scientists say these early encounters with microbes may act as a "thermostat" for the immune system. And they may help explain why Caesarean babies are more likely to have some health problems later in life. The researchers stress women should not swab babies with their vaginal fluids - known as "vaginal seeding". How important are gut bacteria? Our bodies are not entirely human - instead we are an ecosystem with around half our body's cells made up of microbes such as bacteria, viruses and fungi. Most of them live in our gut and are collectively known as our microbiome. The microbiome is linked to diseases including allergy, obesity, inflammatory bowel disease, Parkinson's, whether cancer drugs work and even depression and autism. This study - by Wellcome Sanger Institute, UCL, and the University of Birmingham - assessed how the microbiome forms when we leave our mother's sterile womb and enter a world full of bugs. Regular samples were taken from the nappies of nearly 600 babies for the first month of life, and some provided faecal samples for up to a year. © 2019 BBC

Keyword: Development of the Brain
Link ID: 26637 - Posted: 09.23.2019

Teen girls — but not boys — who prefer to go to bed later are more likely to gain weight, compared to same-age girls who go to bed earlier, suggests a study funded by the National Institutes of Health. The findings by researchers at Kaiser Permanente in Oakland, California, and other institutions appear in JAMA Pediatrics. A total of 804 adolescents (418 girls and 386 boys) ages 11 to 16 took part in the study. The children responded to questionnaires on their sleep habits and wore an actigraph — a wrist device that tracks movement. Researchers measured their waist size and calculated their proportion of body fat using a technique called dual-energy x-ray absorptiometry. They also estimated the children’s social jet lag — the difference between their weeknight and weekend bedtimes. Those who stayed up far later on weekends than weeknights were considered to have high social jet lag. The authors noted that previous studies had found that adults who preferred to stay up late and had high social jet lag were more likely to gain weight than those who went to be earlier and did not have social jet lag. The researchers undertook the current study to determine if the same associations would be seen in young people. For girls, staying up later was associated with an average .58 cm increase in waist size and a .16 kg/m2 increase in body fat. Each hour of social jet lag was associated with a 1.19 cm larger waste size and a 0.45 kg/m2 increase in body fat. These associations were reduced—but still remained—after the researchers statistically adjusted for other factors known to influence weight, such as sleep duration, diet, physical activity and television viewing. Although the researchers found slight associations between these measures and waist size and body fat in boys, they were not statistically significant. The researchers concluded that improving sleep schedules may be helpful in preventing obesity in childhood and adolescence, especially in girls.

Keyword: Obesity; Biological Rhythms
Link ID: 26618 - Posted: 09.17.2019

By Maanvi Singh The world’s most widely used insecticides may delay the migrations of songbirds and hurt their chances of mating. In the first experiment to track the effects of a neonicotinoid on birds in the wild, scientists captured 24 white-crowned sparrows as they migrated north from Mexico and the southern United States to Canada and Alaska. The team fed half of those birds with a low dose of the commonly used agricultural insecticide imidacloprid and the other half with a slightly higher dose. An additional 12 birds were captured and dosed with sunflower oil, but no pesticide. Within hours, the dosed birds began to lose weight and ate less food, researchers report in the Sept. 13 Science. Birds given the higher amount of imidacloprid (3.9 milligrams per kilogram of body mass) lost 6 percent of their body mass within six hours. That’s about 1.6 grams for an average bird weighing 27 grams. Tracking the birds (Zonotrichia leucophrys) revealed that the pesticide-treated sparrows also lagged behind the others when continuing their migration to their summer mating grounds. The findings suggest that neonicotinoid insecticides, already implicated in dropping bee populations, could also have a hand in the decline of songbird populations across North America. From 1966 to 2013, the populations of nearly three-quarters of farmland bird species across the continent have precipitously dropped. The researchers dosed the birds in the lab with carefully measured amounts of pesticide mixed with sunflower oil. In the wild, birds might feed on seeds coated with imidacloprid. The highest dose that “we gave each bird is the equivalent of if they ate one-tenth of [a single] pesticide-coated corn seed,” says Christy Morrissey, a biologist at the University of Saskatchewan in Saskatoon, Canada. “Frankly, these were minuscule doses we gave the birds.” © Society for Science & the Public 2000–2019.

Keyword: Neurotoxins; Obesity
Link ID: 26608 - Posted: 09.13.2019

By Anahad O’Connor Dr. Elaine Yu, an endocrinologist at Massachusetts General Hospital in Boston, was inundated with volunteers when she put out a call a few years ago for overweight people who were willing to take part in a study of obesity and the microbiome. People as far away as Alaska and Hawaii were eager to enroll. But the most surprising part was what they were willing to do. The study required them to swallow capsules containing stool to test whether gut bacteria from lean donors could improve their metabolic health. “We had this concern that it would be difficult to recruit people because there’s a certain yuck factor with having to take a poop pill,” Dr. Yu said. “But we had an overwhelming number of volunteers wanting to participate.” The link between the gut and metabolic disease is a growing area of obesity research. In recent years, scientists have uncovered clues that the microbiota, the community of trillions of microbes that live in the gut, plays a role in weight gain and metabolic disease. Now, in small studies, they are exploring whether they can spur changes in metabolism and potentially in body weight through a therapy known as fecal microbiota transplants, or F.M.T., which transfers gut bacteria from lean donors to the guts of obese patients. The research, which is still in its infancy, has yielded mixed results and plenty of skepticism. Experts say fecal transplants will never replace diet, exercise, behavioral therapies and other standard interventions for obesity and Type 2 diabetes. But some believe they could lead to the discovery of bacteria that protect against metabolic disease, and perhaps become one of many tools that help obese patients who are struggling to shed pounds. “Obesity is a very complex disorder,” said Dr. Jessica Allegretti, the director of the Fecal Microbiota Transplant Program at Brigham and Women’s Hospital. “Perhaps the microbiome is a contributing part of it, and maybe for everyone it’s slightly different. But even for patients where the microbiome is playing a big part, I think this would be something that is part of a larger weight loss program.” © 2019 The New York Times Company

Keyword: Obesity
Link ID: 26597 - Posted: 09.10.2019

By Roni Caryn Rabin Every year, hundreds of thousands of obese Americans undergo weight-loss surgery in a last-ditch effort to shed pounds and control their Type 2 diabetes. Now a new study suggests that bariatric surgery may also have other significant health benefits, cutting the overall risk of serious cardiovascular events and premature death by almost half. The study, published in the medical journal JAMA on Monday, is not definitive. Though it compared the long-term outcomes of about 2,300 bariatric surgery patients with some 11,500 closely matched patients who had not undergone surgery, it was an observational study, not a randomized controlled trial of the kind considered the gold standard in medicine. But the findings were so striking that an editorial accompanying the paper suggested that weight-loss surgery, rather than medications, should be the preferred treatment for Type 2 diabetes in certain patients with obesity. “The new information here is the ability of bariatric surgery to control macrovascular events like strokes, heart attacks, heart failure and kidney disease,” not just improve weight and diabetes control, said Dr. Edward H. Livingston, the editorial’s author. “That’s a big deal.” A bariatric surgeon himself, Dr. Livingston said he had long been known as a “curmudgeon” who was reluctant to make claims about the long-term health benefits of weight-loss surgery. “This is the first time I’ve come out publicly saying, ‘You know what, this may be a better way to go,’” he said, adding that insurers should cover the procedure more liberally. © 2019 The New York Times Company

Keyword: Obesity
Link ID: 26560 - Posted: 09.02.2019

By Anahad O’Connor Low-carbohydrate diets have fallen in and out of favor since before the days of Atkins. But now an even stricter version of low-carb eating called the ketogenic diet is gaining popular attention, igniting a fierce scientific debate about its potential risks and benefits. Both the Atkins and ketogenic diets encourage followers to cut carbs from their diets. But while the Atkins diet gradually increases carbs over time, keto places firm limits on carbs and protein. This way of eating depletes the body of glucose, forcing it to primarily burn fat and produce an alternate source of fuel called ketones. A typical ketogenic diet restricts carbs to less than 10 percent of calories and limits protein to 20 percent, while fat makes up the rest. The keto diet has been popularized in best-selling books, promoted by celebrities and touted on social media as an antidote to various ailments. Proponents say it causes substantial weight loss and can help those with Type 2 diabetes dramatically improve their blood sugar levels, which fall when people avoid carbs. There have been many studies of the ketogenic diet over the years, but most have been small and of fairly short duration. A federal registry of clinical research shows that more than 70 trials looking at the diet’s impact on brain, cardiovascular and metabolic health are either underway or in the beginning stages. Dr. Ethan Weiss, a researcher and preventive cardiologist at the University of California, San Francisco, had long been skeptical of low-carb diets but decided to experiment with the ketogenic diet a couple years ago. In a typical day he skips breakfast and eats mostly salads, nuts, cheese, roasted vegetables and grilled chicken, fish or tofu, as well as dark chocolate for dessert. The result, he says: He lost 20 pounds and had to buy a new wardrobe. © 2019 The New York Times Company

Keyword: Obesity
Link ID: 26520 - Posted: 08.20.2019

By Kate Murphy Maybe it was because when the waiter asked, “Still or sparkling?” you chose sparkling. It could have also been that you were ravenous and ate a little too much. Or, possibly, it was your ex, who happened to be dining at the same restaurant and stood a little too long over your table making awkward small talk. All of these things, hic, might cause spasms, hic, in your diaphragm, hic. Referred to in the medical literature as singultus (from the Latin singult, which means gasp or sob), hiccups are familiar to anyone who has ever taken a breath. In fact, you begin to hiccup while still in the womb. Most people hiccup the most during childhood, with the bouts becoming less frequent over time, but even in adulthood, hiccups are still a common, and annoying, occurrence. Just as we all have our own particular way of sneezing, we all have a unique way of hiccuping that can range from four to 60 hiccups per minute. Most hiccups are benign and last only a few minutes or hours. But sometimes hiccups are indicative of a more serious health issue, particularly when they recur or don’t go away for days, weeks or years. Beyond being embarrassing, the muscle contractions can be physically exhausting. They can interrupt sleep and make it hard to eat. Approximately 4,000 people in the United States are admitted to the hospital every year for hiccups. The patient with the longest recorded case, according to Guinness World Records, was Charles Osborne of Anthon, Iowa, who hiccuped for 68 years straight. He claimed it started while attempting to weigh a hog before slaughtering it. Doctors say there are as many causes for hiccups as there are crazy remedies, including tugging on your tongue, standing on your head and swallowing granulated sugar. Some actually work. Others are more likely just entertainment for friends and family who watch while you try to cure yourself. © 2019 The New York Times Company

Keyword: Miscellaneous
Link ID: 26503 - Posted: 08.15.2019

Tina Hesman Saey Subtle defects in the immune system may lead to obesity and type 2 diabetes, a study of mice suggests. Mice gained weight and developed health problems when they carried a genetic defect that dampens some immune functions, researchers report in the July 26 Science. The immune problems were linked to shifts in the gut microbiome — the collection of friendly bacteria and other microbes living in the intestines. Altering the gut microbe mix, particularly in the small intestine, may lead to increased absorption of fat from the diet, the researchers found. These findings, if they hold up in human studies, could lead to strategies for boosting immune system function in order to help prevent obesity and associated health problems. People with obesity and those with type 2 diabetes also have gut microbe compositions and subtle immune system deficiencies similar to those seen in the mice, says June Round, a microbiome researcher at the University of Utah School of Medicine in Salt Lake City. “It’s possible that things that are happening in our mice are also happening in individual [humans],” she says. Round and colleagues noticed that mice with a defect in the Myd88 gene started gaining weight at about 5 months old. By about a year old, those mice, which lack Myd88 protein in immune cells called T cells, weighed up to 60 grams — about twice as much as a normal mouse. The mutant mice also had developed metabolic problems associated with obesity, such as insulin resistance, a hallmark of type 2 diabetes in people. |© Society for Science & the Public 2000 - 2019

Keyword: Obesity; Neuroimmunology
Link ID: 26453 - Posted: 07.26.2019