 |
|
Live fast, die young? Maybe not
March 10, 2009The theory that a higher metabolism means a shorter lifespan may have reached the end of its own life, thanks to a study published in the journal Physiological and Biochemical Zoology. The study, led by Lobke Vaanholt (University of Groningen, The Netherlands), found that mice with increased metabolism live just as long as those with slower metabolic rates.
The theory that fast-living animals die young, known as the rate-of-living theory, was first proposed in the 1920s. The premise is simple: Aging is the inevitable byproduct of energy expenditure. The faster you expend energy, the faster you age, and the sooner you die. It remained a prominent theory of aging until recently, when comparisons across broad animal groups cast doubt on it. For instance, birds have significantly higher metabolisms than mammals of similar size, yet the birds live much longer.
Vaanholt's study was designed to test the rate-of-living theory among individuals of one species-in this case, mice.
For their experiment, Vaanholt and her team followed two groups of mice through their entire lives. One group's environment was kept at 71 degrees Fahrenheit (22 degrees Celsius), and the other group's at 50 degrees Fahrenheit (10 degrees Celsius). The colder group had to expend more energy to maintain body temperature, and according to the rate-of-living theory, should therefore die sooner than the warm group.
But that's not what happened.
"Despite a 48 percent increase in overall daily energy expenditure and a 64 percent increase in mass-specific energy expenditure throughout adult life, mice in the cold lived just as long on average as mice in warm temperatures," the authors write. "These results strengthen existing doubts about the rate-or-living theory."
The finding is consistent with an experiment Vaanholt conducted previously. That experiment manipulated metabolism in mice through exercise rather than temperature. Mice that expended more energy over a lifetime through exercise had the same lifespan as those that did not exercise.
Both studies cast significant doubt on a theory that just may have burned itself out.
University of Chicago Press Journals
For their experiment, Vaanholt and her team followed two groups of mice through their entire lives. One group's environment was kept at 71 degrees Fahrenheit (22 degrees Celsius), and the other group's at 50 degrees Fahrenheit (10 degrees Celsius). The colder group had to expend more energy to maintain body temperature, and according to the rate-of-living theory, should therefore die sooner than the warm group.
But that's not what happened.
"Despite a 48 percent increase in overall daily energy expenditure and a 64 percent increase in mass-specific energy expenditure throughout adult life, mice in the cold lived just as long on average as mice in warm temperatures," the authors write. "These results strengthen existing doubts about the rate-or-living theory."
The finding is consistent with an experiment Vaanholt conducted previously. That experiment manipulated metabolism in mice through exercise rather than temperature. Mice that expended more energy over a lifetime through exercise had the same lifespan as those that did not exercise.
Both studies cast significant doubt on a theory that just may have burned itself out.
University of Chicago Press Journals
Metabolism Current Events and Metabolism News RSSWomen Can Quit Smoking and Control Weight Gain
Many women don't quit smoking because they are afraid of gaining weight. That's because nicotine suppresses the appetite and boosts a smoker's metabolism.
Scripps research scientists find new link between insulin and core body temperature
A team led by scientists at The Scripps Research Institute have discovered a direct link between insulin-a hormone long associated with metabolism and metabolic disorders such as diabetes-and core body temperature.
Researchers begin to decipher metabolism of sexual assault drug
It's a naturally occurring brain chemical with an unwieldy name: 4-hydroxybutyrate (4-HB). Taken by mouth, it can be abused or used as a date-rape drug.
Cancers' Sweet Tooth May Be Weakness
The pedal-to-the-metal signals driving the growth of several types of cancer cells lead to a common switch governing the use of glucose, researchers at Winship Cancer Institute of Emory University have discovered.
Scientists find molecular trigger that helps prevent aging and disease
Researchers at Mount Sinai School of Medicine set out to address a question that has been challenging scientists for years: How do dietary restriction-and the reverse, overconsumption-produce protective effects against aging and disease?
Night Beat, Overtime and a Disrupted Sleep Pattern Can Harm Officers' Health
A police officer who works the night shift, typically from 8 p.m. to 4 a.m., already is at a disadvantage when it comes to getting a good "night's" sleep.
MIT scientists pinpoint origin of dissolved arsenic in Bangladesh drinking water
Researchers in MIT's Department of Civil and Environmental Engineering believe they have pinpointed a pathway by which arsenic may be contaminating the drinking water in Bangladesh, a phenomenon that has puzzled scientists, world health agencies and the Bangladeshi government for nearly 30 years.
New paper describes connections between Circadian and metabolic systems
A paper by University of Notre Dame biologist Giles Duffield and a team of researchers offers new insights into a gene that plays a key role in modulating the body's Circadian system and may also simultaneously modulate its metabolic system.
New evidence that dark chocolate helps ease emotional stress
The "chocolate cure" for emotional stress is getting new support from a clinical trial published online in ACS' Journal of Proteome Research.
'Escaped' proteins add to hearing loss in elderly, UF researchers find
Age-related hearing loss is the most common sensory disorder among the elderly. But scientists are still trying to figure out what cellular processes govern or contribute to the loss.
More Metabolism Current Events and Metabolism News Articles
 |
Master Your Metabolism: The 3 Diet Secrets to Naturally Balancing Your Hormones for a Hot and Healthy Body! by Jillian Michaels (Author), Mariska van Aalst (Author) Does it feel as if you re fighting your body to lose even one pound or just to maintain your current weight? Respected health and wellness expert and bestselling author Jillian Michaels has been there, too. So she consulted top experts in the field of metabolism and discovered that she d inadvertently been abusing her endocrine system for years. After fixing her own metabolism, she decided to share what she learned by devising this simple, 3-phase plan that engages all the weight-loss hormones (including the friendly HGH, testosterone, DHEA; and the not-so-friendly: insulin, cortisol, and excess estrogen). In Master Your Metabolism, discover how to: REMOVE anti-nutrients from your diet RESTORE foods that speak directly to fat-burning genes REBALANCE energy and your... |
 |
The Metabolism Miracle: 3 Easy Steps to Regain Control of Your Weight... Permanently by Diane Kress (Author) Do you keep gaining weight, despite your efforts to diet? Do the pounds accumulate around your tummy? Do you feel tired, irritable, and unable to focus? If you answered “yes” to any of the above, you may be one of the millions who have Metabolism B, an inherited condition that causes your body to overprocess carbohydrate foods into excess body fat. There is a reason that some people can eat all they want (and seemingly never gain a pound), while the rest of us fret over every carb. Diane Kress, a registered dietitian and weight-loss specialist, has helped thousands with Metabolism B lose weight—and keep it off—with her revolutionary, scientifically based program. Now she shares its secrets here. Among the many life-changing elements of The Metabolism Miracle, you will... |
 |
Fire Up Your Metabolism: 9 Proven Principles for Burning Fat and Losing Weight Forever by Lyssie Lakatos (Author), Tammy Lakatos Shames (Author) "I can't loose weight because I have a terrible metabolism" You may not realize it, but you can take control of your metabolism. Identical twins and registered dietitians, Lyssie Lakatos and Tammy Lakatos Shames embarked on a twin study to determine precisely what does -- and doesn't -- increase the rate at which our bodies burn calories and fat. Their findings? Small changes have big results. The nine weight-loss principles -- and the 200 tips that help you incorporate them into your lifestyle -- in Fire Up Your Metabolism are surprisingly simple: Eat breakfast before you get to work. Learn which sugary snacks trump others (peanut M&Ms boost metabolism, but Twizzlers don't). Drink water, which is essential to burning calories. Always eat dinner, even if it's late.... |
 |
Ultrametabolism: The Simple Plan for Automatic Weight Loss by Mark, M.D. Hyman (Author) For many, losing weight is a never-ending struggle -- especially since our bodies are designed to keep weight on at all costs; it's a matter of survival. But a medical revolution is under way, showing us how to work with our bodies instead of against them to ignite the natural fat-burning furnaces that lie dormant within us. Drawing on the cutting-edge science of nutrigenomics -- how food talks to our genes -- Dr. Mark Hyman has created a way of losing weight by eating the right foods, which in turn sends the right messages to our bodies. In this easy-to-follow eight-week plan based on each individual's unique genetic needs, Dr. Hyman explains how to customize your personal weight-loss program with menus, recipes, shopping lists, and recommendations for supplements and exercise.... |
 |
The Ultimate Metabolism Diet: Eat Right for Your Metabolic Type by Scott Rigden (Author), RN Barbara Schlitz (Contributor) Atkins, the Zone, the South Beach Diet. Anyone with a serious weight problem has probably tried — and failed — to use one of these diets to lose weight. And it’s not their fault. According to weight loss specialist Dr. Scott Rigden, there is no miracle diet that works for everyone because everyone possesses a unique body type and corresponding metabolism. People can be divided into five different metabolic types that have a corresponding plan of specific dietary and lifestyle habits that make weight loss work. In this book, Rigden helps readers determine their metabolic type and then devotes a chapter to each one with dietary, exercise, supplement, and medicine advice complete with glossaries and case studies. He also includes chapters on emotional eating and how to mentally... |
 |
Source Naturals L-Tryptophan, 500 mg, Capsules, 120 capsules by Source Naturals Dietary supplement. Mood, relaxation, sleep. The essential amino acid L-Tryptophan helps support relaxation, restful sleep, and feeling better. It plays a part in the synthesis of both melatonin and serotonin, hormones involved with mood and stress response. L-Tryptophan also supports immune functions because it is the body's precursor to the kynurenines that regulate immunity. If needed, L-Tryptophan converts to niacin in the body, which supports circulation, a healthy nervous system, the metabolism of food, and the production of hydrochloric acid for the digestive system. Source Naturals L-Tryptophan is extremely pure and is regularly tested to ensure the highest standards of quality. (These statements have not been evaluated by the Food and Drug Administration. This product is not... |
 |
Metabolism at a Glance by Jack Salway (Author) Metabolism at a Glance is a complete review course of metabolism in health and disease and offers a unique approach to the study of this difficult discipline. Metabolism is a complicated subject involving complex molecules and interrelated pathways. These metabolic pathways are usually taught separately with the result that the student develops a detailed but compartmentalised approach to metabolism and frequently fails to see the overall picture and its physiological significance. Using the at a Glance format, the book takes the student through a complete course in intermediary metabolism in an integrated manner. The same chart is repeated throughout the book with the individual pathway under study highlighted. The book is an ideal text for introductory biochemistry... |
 |
The Metabolism Advantage: An 8-Week Program to Rev Up Your Body's Fat-Burning Machine---At Any Age by John Berardi Ph.D. C.S.C.S. (Author) With this powerful body transformation program, men and women discover how to kick their metabolism into high gear—and replace flab with lean, fat-burning muscle . . . in just 8 weeks Revving up the body so that it optimizes nutrition and turns flab into lean body mass can be accomplished easily and quickly—and at any age, even after the body’s metabolism has supposedly slowed down. That’s what sought-after fitness trainer and nutrition expert John Berardi demonstrates in this new book. Drawing on the best scientific research, including his own ongoing studies, Berardi has developed a supremely effective plan that enables his clients—who include athletes, models, and ordinary men and women of different fitness levels—to stoke their metabolic fires, burn more... |
 |
Advanced Nutrition and Human Metabolism by Sareen S. Gropper (Author), Jack L. Smith (Author) Current and comprehensive and designed to maximize clarity of the concepts you need to know, longtime best seller ADVANCED NUTRITION AND HUMAN METABOLISM, 5e, delivers its signature quality content in a more student-friendly presentation. With a striking new design, this respected market leader is more accessible, with relevant examples, illustrations, applications, tables, and figures to emphasize key concepts. This text continues to set the standard through the authors' ability to clearly and accurately explain even the most complex metabolic processes and concepts. The authors have updated the art for this edition with easier-to-understand captions that illuminate the processes being shown. It's the only book written for undergraduates that consistently stays at that level. Providing... |
 |
The UltraMetabolism Cookbook: 200 Delicious Recipes that Will Turn on Your Fat-Burning DNA by Mark, M.D. Hyman (Author) From the Three-Time New York Times Bestselling Author of Ultraprevention, Ultrametabolism, and The Ultrasimple Diet In UltraMetabolism, Dr. Mark Hyman brought the new science of weight loss to the general public. By learning to work with the body instead of against it, you can ignite your natural fat-burning furnace and reprogram your body to burn fat and keep it off for good. Simply put, eat the right foods and send instructions of weight loss and health; eat the wrong foods and send messages of weight gain and disease. The UltraMetabolism Cookbook puts Ultra-Metabolism into overdrive with 200 convenient, easy-to-prepare, and, of course, delicious recipes for the right foods that will bring on a lifetime of good health and healthy weight. The first part of... |
| © 2009 BrightSurf.com |