Links for Keyword: Obesity

Follow us on Facebook or subscribe to our mailing list, to receive news updates. Learn more.

Links 1 - 20 of 1162

New Role for Leptin: Promoting Synapse Formation in Rat Neurons

Abby Olena Leptin is a hormone released by fat cells in adult organisms, and researchers have largely focused on how it controls appetite. In a study published May 18 in Science Signaling, the authors show that leptin promotes synapse formation, or synaptogenesis, in developing rodent neurons in culture. “This paper does a really wonderful job [breaking] down the mechanisms” of leptin signaling, and the authors look at changes in synaptic function, not just at the protein level, but also on a physiological level, says Laura Cocas, a neuroscientist at Santa Clara University who was not involved in the study. “Because all of the work on the paper is done in vitro, they can do very careful analysis . . . to break down each step in the signaling pathway.” When Washington State University neuroscientist Gary Wayman and his group started working on leptin about 10 years ago, most of the research had examined the hormone’s function in regulating satiety. But “we and others knew that leptin surged during a critical period of neuronal—and in particular synaptic—development in the brain,” he says. In people, this surge happens during the third trimester of fetal development and, in rodents, over the first few weeks of life. “This surge in leptin is independent of the amount of adipose tissue that’s present. And it does not control feeding during this period because feeding circuits have not developed, so we really wanted to understand what the developmental role was.” Wayman and colleagues focused on the hippocampus because, despite being one of the best-characterized regions in the brain, there wasn’t a lot of information out there about what the leptin receptors present were doing—particularly during development. Multiple groups had also shown that leptin injected in this brain region can improve cognition and act as an antidepressant. © 1986–2021 The Scientist.

Related chapters from BN: Chapter 14: Biological Rhythms, Sleep, and Dreaming; Chapter 17: Learning and Memory
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep; Chapter 13: Memory and Learning
Link ID: 27837 - Posted: 05.29.2021

New Drugs Could Help Treat Obesity. Could They End the Stigma, Too?

By Gina Kolata Obesity has stalked Marleen Greenleaf, 58, all of her life. Like most people with obesity, she tried diet after diet. But the weight always came back. With that, she has suffered a lifetime of scorn and stigma. Jeering comments from strangers when she walked down the street. Family members who told her, when she trained for a half-marathon, “I don’t think it’s good for you.” Then, in 2018, Ms. Greenleaf, an administrator at a charter school in Washington, D.C., participated in a clinical trial for semaglutide, which is a new type of obesity drug, known as incretins. Over the course of the 68-week study, Ms. Greenleaf slowly lost 40 pounds. Until then, she had always believed that she could control her weight if she really tried. “I thought I just needed more motivation,” she said. But when she took semaglutide, she said that “immediately, the urge to eat just dissipated.” Incretins appear to elicit significant weight loss in most patients, enough to make a real medical and aesthetic difference. But experts hope that the drugs also do something else: change how society feels about people with obesity, and how people with obesity feel about themselves. If these new drugs allow obesity to be treated like a chronic disease — with medications that must be taken for a lifetime — the thought is that doctors, patients and the public might understand that obesity is truly a medical condition. © 2021 The New York Times Company

Related chapters from BN: Chapter 13: Homeostasis: Active Regulation of the Internal Environment; Chapter 5: Hormones and the Brain
Related chapters from MM:Chapter 9: Homeostasis: Active Regulation of the Internal Environment; Chapter 8: Hormones and Sex
Link ID: 27821 - Posted: 05.15.2021

Intermittent fasting and why when you eat makes a difference

By Andreas von Bubnoff The world is getting fatter. More than 40 percent of U.S. adults are obese — almost three times more than in 1980. One reason for this weight gain is Americans are consuming more: National figures suggest an increase of about 200 daily calories between the early 1970s and 2010. Another is more snacking. In 2010, U.S. adults ate about 20 percent more of their daily calories as snacks than they did 50 years ago. But there is more to rising obesity rates than endless grazing. What also matters is timing, some experts believe. We eat when we shouldn’t, and don’t give our bodies a long enough break in between. We didn’t evolve to eat day and night, says neuroscientist Dominic D’Agostino of the University of South Florida. Until the dawn of agriculture about 12,000 years ago, we subsisted on hunting and gathering and often had to perform those activities with empty bellies. “We are hard-wired,” D’Agostino says, “to undergo periodic intermittent fasting.” What’s more, people are now eating at times of the day when historically they would have been asleep, says Satchin Panda, a circadian biologist at the Salk Institute for Biological Studies in La Jolla, Calif., who co-wrote an overview on the timing of eating in the 2019 Annual Review of Nutrition. For thousands of years, he says, our nightly fast probably started much earlier than in these times of late-night television. Although the research is still mixed, the timing of eating seems to matter for body weight and health. Studies suggest significant potential benefits from fasting every other day or so — or, on a daily basis, eating only when we would normally be awake, within a window of 12 hours or fewer — a practice known as time-restricted eating. © 1996-2021 The Washington Post

Related chapters from BN: Chapter 13: Homeostasis: Active Regulation of the Internal Environment
Related chapters from MM:Chapter 9: Homeostasis: Active Regulation of the Internal Environment
Link ID: 27710 - Posted: 02.28.2021

Unhealthy Foods Aren’t Just Bad For You, They May Also Be Addictive

By Anahad O’Connor Five years ago, a group of nutrition scientists studied what Americans eat and reached a striking conclusion: More than half of all the calories that the average American consumes comes from ultra-processed foods, which they defined as “industrial formulations” that combine large amounts of sugar, salt, oils, fats and other additives. Highly processed foods continue to dominate the American diet, despite being linked to obesity, heart disease, Type 2 diabetes and other health problems. They are cheap and convenient, and engineered to taste good. They are aggressively marketed by the food industry. But a growing number of scientists say another reason these foods are so heavily consumed is that for many people they are not just tempting but addictive, a notion that has sparked controversy among researchers. Recently, the American Journal of Clinical Nutrition explored the science behind food addiction and whether ultra-processed foods might be contributing to overeating and obesity. It featured a debate between two of the leading experts on the subject, Ashley Gearhardt, associate professor in the psychology department at the University of Michigan, and Dr. Johannes Hebebrand, head of the department of child and adolescent psychiatry, psychosomatics and psychotherapy at the University of Duisburg-Essen in Germany. Dr. Gearhardt, a clinical psychologist, helped develop the Yale Food Addiction Scale, a survey that is used to determine whether a person shows signs of addictive behavior toward food. In one study involving more than 500 people, she and her colleagues found that certain foods were especially likely to elicit “addictive-like” eating behaviors, such as intense cravings, a loss of control, and an inability to cut back despite experiencing harmful consequences and a strong desire to stop eating them. At the top of the list were pizza, chocolate, potato chips, cookies, ice cream, French fries and cheeseburgers. © 2021 The New York Times Company

Related chapters from BN: Chapter 13: Homeostasis: Active Regulation of the Internal Environment; Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Related chapters from MM:Chapter 9: Homeostasis: Active Regulation of the Internal Environment; Chapter 4: Development of the Brain
Link ID: 27706 - Posted: 02.23.2021

‘A Game Changer’: Drug Brings Weight Loss in Patients With Obesity

By Gina Kolata For the first time, a drug has been shown so effective against obesity that patients may dodge many of its worst consequences, including diabetes, researchers reported on Wednesday. The drug, semaglutide, made by Novo Nordisk, already is marketed as a treatment for Type 2 diabetes. In a clinical trial published in the New England Journal of Medicine, researchers at Northwestern University in Chicago tested semaglutide at a much higher dose as an anti-obesity medication. Nearly 2,000 participants, at 129 centers in 16 countries, injected themselves weekly with semaglutide or a placebo for 68 weeks. Those who got the drug lost close to 15 percent of their body weight, on average, compared with 2.4 percent among those receiving the placebo. More than a third of the participants receiving the drug lost more than 20 percent of their weight. Symptoms of diabetes and pre-diabetes improved in many patients. Those results far exceed the amount of weight loss observed in clinical trials of other obesity medications, experts said. The drug is a “game-changer,” said Dr. Robert F. Kushner, an obesity researcher at Northwestern University Feinberg School of Medicine, who led the study. “This is the start of a new era of effective treatments for obesity.” Dr. Clifford Rosen of Maine Medical Center Research Institute, who was not involved in the trial, said, “I think it has a huge potential for weight loss.” Gastrointestinal symptoms among the participants were “really marginal — nothing like with weight loss drugs in the past,” added Dr. Rosen, an editor at the New England Journal of Medicine and a co-author of an editorial accompanying the study. For decades, scientists have searched for ways to help growing numbers of people struggling with obesity. Five currently available anti-obesity drugs have side effects that limit their use. The most effective, phentermine, brings about a 7.5 percent weight loss, on average, and can be taken only for a short time. After it is stopped, even that amount of weight is regained. © 2021 The New York Times Company

How gut microbes could drive brain disorders

Cassandra Willyard In 2006, soon after she launched her own laboratory, neuroscientist Jane Foster discovered something she felt sure would set her field abuzz. She and her team were working with two groups of mice: one with a healthy selection of microorganisms in their guts, and one that lacked a microbiome. They noticed that the mice without gut bacteria seemed less anxious than their healthy equivalents. When placed in a maze with some open paths and some walled-in ones, they preferred the exposed paths. The bacteria in the gut seemed to be influencing their brain and behaviour. Foster, at McMaster University in Toronto, Canada, wrote up the study and submitted it for publication. It was rejected. She rewrote it and sent it out again. Rejected. “People didn’t buy it. They thought it was an artefact,” she says. Finally, after three years and seven submissions, she got an acceptance letter1. John Cryan, a neuroscientist at University College Cork in Ireland, joined the field about the same time as Foster did, and knows exactly how she felt. When he began talking about the connections between bacteria living in the gut and the brain, “I felt very evangelical”, he says. He recalls one Alzheimer’s disease conference at which he presented in 2014. “I’ve never given a talk in a room where there was less interest.” Today, however, the gut–brain axis is a feature at major neuroscience meetings, and Cryan says he is no longer “this crazy guy from Ireland”. Thousands of publications over the past decade have revealed that the trillions of bacteria in the gut could have profound effects on the brain, and might be tied to a whole host of disorders. Funders such as the US National Institutes of Health are investing millions of dollars in exploring the connection. © 2021 Springer Nature Limited

To Lose Weight With Exercise, Aim for 300 Minutes a Week

By Gretchen Reynolds Can exercise help us shed pounds? An interesting new study involving overweight men and women found that working out can help us lose weight, in part by remodeling appetite hormones. But to benefit, the study suggests, we most likely have to exercise a lot — burning at least 3,000 calories a week. In the study, that meant working out six days a week for up to an hour, or around 300 minutes a week. The relationship between working out and our waistlines is famously snarled. The process seems as if it should straightforward: We exercise, expend calories and, if life and metabolisms were just, develop an energy deficit. At that point, we would start to use stored fat to fuel our bodies’ continuing operations, leaving us leaner. But our bodies are not always cooperative. Primed by evolution to maintain energy stores in case of famine, our bodies tend to undermine our attempts to drop pounds. Start working out and your appetite rises, so you consume more calories, compensating for those lost. The upshot, according to many past studies of exercise and weight loss, is that most people who start a new exercise program without also strictly monitoring what they eat do not lose as much weight as they expect — and some pack on pounds. But Kyle Flack, an assistant professor of nutrition at the University of Kentucky, began to wonder a few years ago if this outcome was inevitable. Maybe, he speculated, there was a ceiling to people’s caloric compensations after exercise, meaning that if they upped their exercise hours, they would compensate for fewer of the lost calories and lose weight. © 2020 The New York Times Company

Where You Carry Body Fat May Affect How Long You Live

By Nicholas Bakalar Being overweight is linked to an increased risk for premature death, but which part of the body carries the added fat could make a big difference. Extra weight in some places may actually lower the risk. Researchers, writing in BMJ, reviewed 72 prospective studies that included more than two and a half million participants with data on body fat and mortality. They found that central adiposity — a large waist — was consistently associated with a higher risk of all-cause mortality. In pooled data from 50 studies, each four-inch increase in waist size was associated with an 11 percent increased relative risk for premature death. The association was significant after adjusting for smoking, physical activity and alcohol consumption. Waist size is an indicator of the amount of visceral fat, or fat stored in the abdomen around the internal organs. This kind of fat is associated with an increased risk for heart disease, Type 2 diabetes, cancer and Alzheimer’s disease. But increased fat in two places appears to be associated with a lower risk of death. Three studies showed that each two-inch increase in thigh circumference was associated with an 18 percent lower risk of all-cause mortality. In nine studies involving almost 300,000 participants, a four-inch increase in a woman’s hip circumference was associated with a 10 percent lower risk of death. “Thigh size is an indicator of the amount of muscle, which is protective,” said a co-author of the review, Tauseef Ahmad Khan, a postdoctoral fellow at the University of Toronto. “And hip fat is not visceral fat, but subcutaneous fat, which is considered beneficial.” © 2020 The New York Times Company

The Underused Weight Loss Option: Bariatric Surgery

By Jane E. Brody Growing rates of obesity among Americans are clear evidence that even the best intentions and strongest motivations are often not enough to help seriously overweight people lose a significant amount of weight and, more important, keep it off. But for those who can overcome fears of surgery and perhaps do battle with recalcitrant insurers, there remains another very successful option that experts say is currently vastly underused. That option is bariatric surgery, an approach that is now simpler, safer and more effective than in its early days in the 1990s. “Only one-half of 1 percent of people eligible for bariatric surgery currently undergo it,” Dr. Anne P. Ehlers, a bariatric surgeon at the University of Michigan, told me. Bariatric surgery is generally considered a treatment option for people with a body mass index (B.M.I.) of 40 or more who failed to lose weight with diet and exercise alone. It is also recommended for those with lesser degrees of obesity — a B.M.I. of 30 to 35 — who have obesity-related medical conditions. The underuse of weight-loss surgery has been largely attributed to “the reluctance of the medical community and patients to accept surgery as a safe, effective and durable treatment of obesity,” other experts at the University of Michigan wrote in JAMA in 2018. They added that patients “may be reluctant to pursue surgical treatment because they may be judged by others for taking the easy way out and not having the willpower to diet and exercise.” © 2020 The New York Times Company

Losing 13 percent of your weight could lead to big improvements in your health

By Linda Searing If you’re obese, losing just 5 percent of your weight starts you on the path to better health, but new research finds that losing 13 percent of your weight may make a good-size dent in your chances of developing several unhealthy conditions. For instance, the odds of developing Type 2 diabetes were at least 42 percent lower among obese people who lost that much weight than for those who did not lose weight, according to a report from the European and International Congress on Obesity. The research was based on eight years of data on 552,953 middle-aged adults who were obese and intentionally lost weight (meaning their weight loss did not occur because of an illness). Besides the diabetes effect, losing 13 percent of their weight also made people 25 percent less likely to develop high blood pressure or sleep apnea, and it correlated to a 22 percent risk reduction for high cholesterol and a 20 percent lower risk for osteoarthritis. Obesity, defined as excessive fat accumulation that presents a risk to health, is often determined by a person’s body mass index (BMI), a calculation of body fatness based on weight and height. The simplest way to figure your BMI is to plug your height and weight into an online calculator. A BMI of 30 or above is considered obese. Treatment for obesity usually starts with a modest weight-loss goal of 5 to 10 percent (10 to 20 pounds for someone weighing 200) and includes a change in eating habits and an increase in physical activity.

Can Artificial Sweeteners Keep Us From Gaining Weight?

By Anahad O’Connor Artificial sweeteners hold the promise of satisfying your sweet tooth without the downside of excess calories, and they are increasingly used in products ranging from diet sodas and powdered drink mixes to yogurt and baked goods. But whether using them can prevent weight gain — a problem many people are struggling with during the coronavirus lockdowns — has long been an open question. Now some studies are providing answers. Researchers have found that artificial sweeteners can be useful as a tool to help people kick their sugar habits, and that for some people, replacing sugar with nonnutritive sweeteners can indeed help stave off weight gain. But they can also have effects on hormones, blood sugar and other aspects of metabolism that some experts say are concerning, and they caution against consuming them routinely for long periods of time. “The idea we need to get rid of is that because they have zero calories they have zero metabolic effects,” said Marta Yanina Pepino, an assistant professor in the department of food science and human nutrition at the University of Illinois at Urbana-Champaign. “Our data suggests that they are metabolically active, and depending on how frequently you use them, some people can see more effects than others.” Purchases of foods and beverages containing sugar substitutes have risen as health-conscious consumers cut back on sugar. Diet beverages account for the largest source of these sweeteners in the American diet. Among the most popular sugar substitutes are sucralose, also known as Splenda, and aspartame, which is found in Diet Coke, Diet Pepsi and thousands of other foods. Stevia, a zero-calorie plant extract that is marketed as natural, is also widely used in many products as a sugar substitute. In a report published recently in the Journal of the American Heart Association, researchers at Boston Children’s Hospital studied what happened when soda drinkers switched to drinking water or beverages that were artificially sweetened. The researchers recruited 203 adults who consumed at least one sugary beverage daily; only some of them were overweight. © 2020 The New York Times Company

Obesity not defined by weight, says new Canada guideline

Obesity should be defined by a person's health - not just their weight, says a new Canadian clinical guideline. It also advises doctors to go beyond simply recommending diet and exercise. Instead, they should focus on the root causes of weight gain and take a holistic approach to health. The guideline, which was published in the Canadian Medical Association Journal on Tuesday, specifically admonished weight-related stigma against patients in the health system. "The dominant cultural narrative regarding obesity fuels assumptions about personal irresponsibility and lack of willpower and casts blame and shame upon people living with obesity," the guideline, which is intended to be used by primary care physicians in diagnosing and treating obesity in their daily practice, states. Ximena Ramos-Salas, the director of research and policy at Obesity Canada and one of the guideline's authors, said research shows many doctors discriminate against obese patients, and that can lead to worse health outcomes irrespective of their weight. "Weight bias is not just about believing the wrong thing about obesity," she told the BBC. "Weight bias actually has an effect on the behaviour of healthcare practitioners." The rate of obesity has tripled over the past three decades in Canada, and now about one in four Canadians is obese according to Statistics Canada. The guideline had not been updated since 2006. The new version was funded by Obesity Canada, the Canadian Association of Bariatric Physicians and Surgeons and the Canadian Institutes of Health Research through a Strategy for Patient-Oriented Research grant. Although the latest advice still recommends using diagnostic criteria like the body mass index (BMI) and waist circumference, it acknowledges their clinical limitations and says doctors should focus more on how weight impacts a person's health. Small reductions in weight, of about 3-5%, can lead to health improvements and an obese person's "best weight" might not be their "ideal weight" according to BMI, the guideline says. It emphasises that obesity is a complex, chronic condition that needs lifelong management. © 2020 BBC.

A Chemist’s Skeptical Look at Nutritional Wisdom

By Abigail Zuger, M.D. Do I dare to eat a Cheeto? I do not; I can’t even let one into the house. The same goes for its delectably plump twin, the Cheez Doodle; its tasty rotund cousin, the Cheez Ball; and its heavenly brother by another mother, that sandwich of two Cheezy crackers glued together with peanut butter. I dare not even walk down the supermarket aisle where this neon orange family lives, for while others may succumb to chocolate or pastry, my Waterloo is this cheesy goodness — let’s call it Cheez. One Cheez Doodle would lead to a bag, then to more bags, and then to the certain catastrophe of a larger, sicker me. I know these delicacies are terrible for a person’s health. How exactly do I know that? It’s not because I’m a medical professional, that’s for sure; there were zero discussions of Cheez in our pre- or post-graduate training. I know because I just know, is all. Overprocessed chemical-laden stuff is bad for you; it’s pure malevolent junk. Everyone knows that. George Zaidan, an MIT-trained chemist of contrarian bent, knows it too. That is, he knows it to be piously reiterated received wisdom, and thus legitimate fodder for dissection, examination, refutation, and cheerfully self-indulgent obscenity-laden riffs. Further, he has chosen this junk food truth as an excellent starting point for “Ingredients: The Strange Chemistry of What We Put in Us and On Us,” an entertaining and enlightening jaunt around the perimeters of exactly what we can ever hope science can teach us about stuff that is good and bad for us. And it all begins with a single Cheeto, the putative first brick on the winding golden road to nutritional hell.

Study shows brain and stomach connections are a two-way street

By David Templeton For much of the 20th century, most people thought that stress caused stomach ulcers. But that belief was largely dismissed 38 years ago when a study, which led to a Nobel Prize in 2016, described the bacterium that generates inflammation in the gastrointestinal tract and causes peptic ulcers and gastritis. “The history of the idea that stress causes ulcers took a side step with the discovery of Helicobacter pylori,” said Dr. David Levinthal, director of the University of Pittsburgh Neurogastroenterology & Motility Center. “For the longest time — most of the 20th century — the dominant idea was that stress was the cause of ulcers until the early 1980s with discovery of Helicobacter pylori that was tightly linked to the risk of ulcers. That discovery was critical but maybe over-generalized as the only cause of ulcers.” Now in an important world first, a study co-authored by Levinthal and Peter Strick, both from the Pitt School of Medicine, has explained what parts of the brain’s cerebral cortex influence stomach function and how it can affect health. “Our study shows that the activity of neurons in the cerebral cortex, the site of conscious mental function, can impact the ability of bacteria to colonize the stomach and make the person more sensitive to it or more likely to harbor the bacteria,” Levinthal said. The study goes far beyond ulcers by also providing evidence against the longstanding belief that the brain’s influence on the stomach was more reflexive and with limited, if any, involvement of the thinking brain. And for the first time, the study also provides a general blueprint of neural wiring that controls the gastrointestinal tract. © 2020 StarTribune.

Obesity Linked to Severe Coronavirus Disease, Especially for Younger Patients

By Roni Caryn Rabin Obesity may be one of the most important predictors of severe coronavirus illness, new studies say. It’s an alarming finding for the United States, which has one of the highest obesity rates in the world. Though people with obesity frequently have other medical problems, the new studies point to the condition in and of itself as the most significant risk factor, after only older age, for being hospitalized with Covid-19, the illness caused by the coronavirus. Young adults with obesity appear to be at particular risk, studies show. The research is preliminary, and not peer reviewed, but it buttresses anecdotal reports from doctors who say they have been struck by how many seriously ill younger patients of theirs with obesity are otherwise healthy. No one knows why obesity makes Covid-19 worse, but hypotheses abound. Some coronavirus patients with obesity may already have compromised respiratory function that preceded the infection. Abdominal obesity, more prominent in men, can cause compression of the diaphragm, lungs and chest capacity. Obesity is known to cause chronic, low-grade inflammation and an increase in circulating, pro-inflammatory cytokines, which may play a role in the worst Covid-19 outcomes. Some 42 percent of American adults — nearly 80 million people — live with obesity. That is a prevalence rate far exceeding those of other countries hit hard by the coronavirus, like China and Italy. The new findings about obesity risks are bad news for all Americans, but particularly for African-Americans and other people of color, who have higher rates of obesity and are already bearing a disproportionate burden of Covid-19 deaths. High rates of obesity are also prevalent among low-income white Americans, who may also be adversely affected, experts say. More than half of Covid-19 deaths in the United States so far have been in New York and New Jersey, but the new findings mean the coronavirus could exact a steep toll in regions like the South and the Midwest, where obesity is more prevalent than in the Northeast. © 2020 The New York Times Company

Related chapters from BN: Chapter 13: Homeostasis: Active Regulation of the Internal Environment; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 9: Homeostasis: Active Regulation of the Internal Environment; Chapter 11: Emotions, Aggression, and Stress
Link ID: 27205 - Posted: 04.17.2020

Your brain evolved to hoard supplies and shame others for doing the same

Stephanie Preston The media is replete with COVID-19 stories about people clearing supermarket shelves – and the backlash against them. Have people gone mad? How can one individual be overfilling his own cart, while shaming others who are doing the same? As a behavioral neuroscientist who has studied hoarding behavior for 25 years, I can tell you that this is all normal and expected. People are acting the way evolution has wired them. The word “hoarding” might bring to mind relatives or neighbors whose houses are overfilled with junk. A small percentage of people do suffer from what psychologists call “hoarding disorder,” keeping excessive goods to the point of distress and impairment. But hoarding is actually a totally normal and adaptive behavior that kicks in any time there is an uneven supply of resources. Everyone hoards, even during the best of times, without even thinking about it. People like to have beans in the pantry, money in savings and chocolates hidden from the children. These are all hoards. Most Americans have had so much, for so long. People forget that, not so long ago, survival often depended on working tirelessly all year to fill root cellars so a family could last through a long, cold winter – and still many died. Similarly, squirrels work all fall to hide nuts to eat for the rest of the year. Kangaroo rats in the desert hide seeds the few times it rains and then remember where they put them to dig them back up later. A Clark’s nutcracker can hoard over 10,000 pine seeds per fall – and even remember where it put them. © 2010–2020, The Conversation US, Inc.

Related chapters from BN: Chapter 13: Homeostasis: Active Regulation of the Internal Environment; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 9: Homeostasis: Active Regulation of the Internal Environment; Chapter 14: Attention and Higher Cognition
Link ID: 27149 - Posted: 03.30.2020

How to Lose Weight and Keep It Off

By Jane E. Brody Many people who have struggled for years with excess weight know that the hardest and often the most frustrating job is not getting it off but keeping it off. Recent decades have seen countless popular diet schemes that promised to help people shed unwanted pounds, and as each of these diets failed in the long run, they spawned their successors. A diet, after all, is something people go on to go off. Most people think of a diet as a means to an end, and few who go on a food-restricted diet to lose weight expect to have to eat that way indefinitely. And therein lies the rub, with the current unchecked epidemic of obesity as the sorry result. We live in a land of incredible excess. Rich or poor, most of us are surrounded by calorie-rich vittles, many of them tasty but deficient in ingredients that nourish healthy bodies. “We can’t go two minutes without being assaulted by a food cue,” said Suzanne Phelan, lead author of an encouraging new study in the journal Obesity. Even the most diligent dieters can find it hard to constantly resist temptation. And once people fall off the diet wagon, they often stay off, and their hard-lost pounds reappear a lot faster than it took to shed them. But these facts need not discourage anyone from achieving lasting weight loss. Researchers have identified the strategies and thought processes that have enabled many thousands of people to lose a significant amount of weight and keep it off for many years, myself among them. The new study led by Dr. Phelan, professor of kinesiology and public health at California Polytechnic State University, identified habits and strategies that can be keys to success for millions. Yes, like most sensible weight-loss plans, they involve healthful eating and regular physical activity. But they also include important self-monitoring practices and nonpunitive coping measures that can be the crucial to long-term weight management. © 2020 The New York Times Company

A common artificial sweetener might be making you fatter and sicker,

Laura Reiley A study published in the journal Cell Metabolism by a group of Yale researchers found that the consumption of the common artificial sweetener sucralose (which is found in Splenda, Zerocal, Sukrana, SucraPlus and other brands) in combination with carbohydrates can swiftly turn a healthy person into one with high blood sugar. From whole grain English muffins to reduced-sugar ketchup, sucralose is found in thousands of baked goods, condiments, syrups and other consumer packaged goods — almost all of them containing carbs. The finding, which researchers noted has yet to be replicated in other studies, raises new questions about the use of artificial sweeteners and their effects on weight gain and overall health. In the Yale study, researchers took 60 healthy-weight individuals and separated them into three groups: A group that consumed a regular-size beverage containing the equivalent of two packets of sucralose sweetener, a second group that consumed a beverage sweetened with table sugar at the equivalent sweetness, and a third control group that had a beverage with the artificial sweetener as well as a carbohydrate called maltodextrin. The molecules of maltodextrin don’t bind to taste receptors in the mouth and are impossible to detect. While the sensation of the third group’s beverage was identical to the Splenda-only group, only this group exhibited significant adverse health effects. The artificial sweetener by itself seemed to be fine, the researchers discovered, but that changed when combined with a carbohydrate. Seven beverages over two weeks and the previously healthy people in this group became glucose intolerant, a metabolic condition that results in elevated blood glucose levels and puts people at an increased risk for diabetes.

Related chapters from BN: Chapter 13: Homeostasis: Active Regulation of the Internal Environment; Chapter 9: Hearing, Balance, Taste, and Smell
Related chapters from MM:Chapter 9: Homeostasis: Active Regulation of the Internal Environment; Chapter 6: Hearing, Balance, Taste, and Smell
Link ID: 27113 - Posted: 03.12.2020

Your Kids Are Heavier Than You Think

By Susana Martinez-Conde Parents tend to be just a bit biased about their children’s looks (not me though—my kids are objectively beautiful), but as it turns out, this type of self-deception is not as benign as one might think. According to recent research, many parents appear to suffer from a sort of denial concerning their kids’ weights, which poses a considerable obstacle to remediating childhood obesity by way of promoting healthy eating habits at home. The latest of such studies was published last month in the American Journal of Human Biology, and conducted by a team of scientists at the University of Coimbra in Portugal. Daniela Rodrigues and her collaborators, Aristides Machado-Rodrigues and Cristina Padez, recruited hundreds of parents and children for their research. All the participating children were between 6 and 10 years old and attended elementary school in Portugal. A total of 834 parents completed questionnaires that included a variety of questions, such as whether they thought that their children’s weight was a bit too little, a bit too much, way too much, or just fine. In turn, the team collected the weights and heights of the 793 participating children, at their respective schools. The results were in line with the researchers’ predictions, but nonetheless remarkable. Of the 33% parents who misperceived their children’s weight, 93% underestimated it. Moreover, parents who underestimated their kids’ weights were 10 to 20 times more likely to have an obese child. Several factors were associated with the parental weight underestimation, including a higher BMI (body mass index) for the mothers, younger ages for the children, lower household income (for girls) and urban living (for boys). However, such associations did not explain why parents underestimated their children’s weights to begin with. © 2020 Scientific American

Related chapters from BN: Chapter 18: Attention and Higher Cognition; Chapter 13: Homeostasis: Active Regulation of the Internal Environment
Related chapters from MM:Chapter 14: Attention and Higher Cognition; Chapter 9: Homeostasis: Active Regulation of the Internal Environment
Link ID: 27106 - Posted: 03.09.2020

How Exercise Might Affect Our Food Choices, and Our Weight

By Gretchen Reynolds Taking up exercise could alter our feelings about food in surprising and beneficial ways, according to a compelling new study of exercise and eating. The study finds that novice exercisers start to experience less desire for fattening foods, a change that could have long-term implications for weight control. The study also shows, though, that different people respond quite differently to the same exercise routine and the same foods, underscoring the complexities of the relationship between exercise, eating and fat loss. I frequently write about exercise and weight, in part because weight control is a pressing motivation for so many of us to work out, myself included. But the effects of physical activity on waistlines are not straightforward and coherent. They are, in fact, distressingly messy. Both personal experience and extensive scientific studies tell us that a few people will lose considerable body fat when they start exercising; others will gain; and most will drop a few pounds, though much less than would be expected given how many calories they are burning during their workouts. At the same time, physical activity seems to be essential for minimizing weight gain as we age and maintaining weight loss if we do manage to shed pounds. Precisely how exercise influences weight in this topsy-turvy fashion is uncertain. On the one hand, most types of exercise increase appetite in most people, studies show, tempting us to replace calories, blunting any potential fat loss and even initiating weight creep. But other evidence suggests that physical fitness may affect people’s everyday responses to food, which could play a role in weight maintenance. In some past studies, active people of normal weight displayed less interest in high-fat, calorie-dense foods than inactive people who were obese. © 2020 The New York Times Company

Links By Chapter:

Links for Keyword: Obesity