Category: Stroke

New research suggests diet soda may do more harm than good

On By A.P.In acesulfame potassium, American Beverage Association, artificial sweetener, aspartame, Diabetes, diet soda, Equal, heart disease, insulin, Medicine, Melina Jampolis, neotame, NutraSweet, Obesity, Purdue University, saccharin, Splenda, Stroke, sucralose, SugarTwin, Sunett, Susan Swithers, Sweet One, Sweet'N Low, Trends in Endocrinology & MetabolismLeave a comment

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Diet soda drinkers have the same health issues as those who drink regular soda, according to a new report published Wednesday.

Purdue University researchers reviewed a dozen studies published in past five years that examined the relationship between consuming diet soda and health outcomes for the report, published as an opinion piece in the journal Trends in Endocrinology & Metabolism. They say they were “shocked” by the results.

“Honestly, I thought that diet soda would be marginally better compared to regular soda in terms of health,” said Susan Swithers, the report’s author and a behavioral neuroscientist and professor of psychological sciences. “But in reality it has a counterintuitive effect.”

Artificial sweeteners in diet soda fulfill a person’s craving for a sweet taste, without the calories. But that’s the problem, according to researchers. Think of it like crying wolf.

Fake sugar teases your body by pretending to give it real food. But when your body doesn’t get the things it expects to get, it becomes confused on how to respond.

“You’ve messed up the whole system, so when you consume real sugar, your body doesn’t know if it should try to process it because it’s been tricked by the fake sugar so many times,” says Swithers.

On a physiological level, this means when diet soda drinkers consume real sugar, the body doesn’t release the hormone that regulates blood sugar and blood pressure.

Diet soda drinkers also tend to pack on more pounds than those who don’t drink it, the report says.

“The taste of sweet does cause the release of insulin, which lowers blood sugar , and if carbohydrates are not consumed, it causes a drop in blood sugar, which triggers hunger and cravings for sugar,” says CNN diet and fitness expert Dr. Melina Jampolis.

The artificial sweeteners also dampen the “reward center” in your brain, which may lead you to indulge in more calorie-rich, sweet-tasting food, according to the report.

The American Beverage Association says the report was “an opinion piece, not a scientific study.

“Low-calorie sweeteners are some of the most studied and reviewed ingredients in the food supply today,” the association said in a statement. “They are safe and an effective tool in weight loss and weight management, according to decades of scientific research and regulatory agencies around the globe.”

Diet soda’s negative effects are not just linked to weight gain, however, the report says.

It found that diet soda drinkers who maintained a healthy weight range still had a significantly increased risk of the top three killers in the United States: diabetes, heart disease and stroke.

“We’ve gotten to a place where it is normal to drink diet soda because people have the false impression that it is healthier than indulging in a regular soda,” says Swithers. “But research is now very clear that we need to also be mindful of how much fake sugar they are consuming.”

There are five FDA-approved artificial sweeteners: acesulfame potassium (Sunett, Sweet One), aspartame (Equal, NutraSweet), neotame, saccharin (SugarTwin, Sweet’N Low), and sucralose (Splenda).

“Saccharin was one of the first commercially-available artificially sweeteners, and it’s actually a derivative of tar,” says Swithers.

Even natural sweeteners like Stevia, which has no calories and is 250 times sweeter than regular sugar, are still processed extracts of a natural plant and may have increased health risks.

“Just because something is natural does not always mean that it is safer,” says Jampolis.

There more studies and research that need to be done. But in the meantime, experts say: Limit consumption.

“No one is saying cut it out completely,” says Swithers. “But diet soda should be a treat or indulgence just like your favorite candy, not an everyday
thing.”

Study: Diet soda may do more harm than good

Flip of a single molecular switch makes an old brain young

On By A.P.In adolescent brain, aged brain, aging, Axerion Therapeutics, brain, Feras Akbik, learning, memory, National Institutes of Health, neural activity, Neuron, neuroplasticity, Neuroscience, neuroscientist, Nogo Receptor 1, plasticity, post-traumatic stress disorder, PTSD, Pujan Patel, Pujan R. Patel, rehabilitation, Sarah Bhagat, Sarah M. Bhagat, Science, Stephen Strittmatter, Stroke, synapse, The Brain, Traumatic Brain Injury, William B.J. Cafferty, William Cafferty, Yale University1 Comment

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The flip of a single molecular switch helps create the mature neuronal connections that allow the brain to bridge the gap between adolescent impressionability and adult stability. Now Yale School of Medicine researchers have reversed the process, recreating a youthful brain that facilitated both learning and healing in the adult mouse.

Scientists have long known that the young and old brains are very different. Adolescent brains are more malleable or plastic, which allows them to learn languages more quickly than adults and speeds recovery from brain injuries. The comparative rigidity of the adult brain results in part from the function of a single gene that slows the rapid change in synaptic connections between neurons.

By monitoring the synapses in living mice over weeks and months, Yale researchers have identified the key genetic switch for brain maturation a study released March 6 in the journal Neuron. The Nogo Receptor 1 gene is required to suppress high levels of plasticity in the adolescent brain and create the relatively quiescent levels of plasticity in adulthood. In mice without this gene, juvenile levels of brain plasticity persist throughout adulthood. When researchers blocked the function of this gene in old mice, they reset the old brain to adolescent levels of plasticity.

“These are the molecules the brain needs for the transition from adolescence to adulthood,” said Dr. Stephen Strittmatter. Vincent Coates Professor of Neurology, Professor of Neurobiology and senior author of the paper. “It suggests we can turn back the clock in the adult brain and recover from trauma the way kids recover.”

Rehabilitation after brain injuries like strokes requires that patients re-learn tasks such as moving a hand. Researchers found that adult mice lacking Nogo Receptor recovered from injury as quickly as adolescent mice and mastered new, complex motor tasks more quickly than adults with the receptor.

“This raises the potential that manipulating Nogo Receptor in humans might accelerate and magnify rehabilitation after brain injuries like strokes,” said Feras Akbik, Yale doctoral student who is first author of the study.

Researchers also showed that Nogo Receptor slows loss of memories. Mice without Nogo receptor lost stressful memories more quickly, suggesting that manipulating the receptor could help treat post-traumatic stress disorder.

“We know a lot about the early development of the brain,” Strittmatter said, “But we know amazingly little about what happens in the brain during late adolescence.”

Other Yale authors are: Sarah M. Bhagat, Pujan R. Patel and William B.J. Cafferty

The study was funded by the National Institutes of Health. Strittmatter is scientific founder of Axerion Therapeutics, which is investigating applications of Nogo research to repair spinal cord damage.

http://news.yale.edu/2013/03/06/flip-single-molecular-switch-makes-old-brain-young

New study shows that getting less than 6 hours of sleep a night significantly increases risk of stroke

On By A.P.In Alabama, Birmingham, Health, obstructive sleep apnea, Stroke, University of Alabama at BirminghamLeave a comment

Getting a good night’s rest continues to be of utmost importance to your health. New data from researchers at the University of Alabama at Birmingham shows too little sleep can increase the risk for stroke symptoms in people with a healthy body-mass index who are at low risk for obstructive sleep apnea and have no history of stroke.

The study, being presented June 11, 2012, at the SLEEP 2012conference in Boston, looked at self-reported sleep data from 5,666 people ages 45 and older who were followed up to a three-year period. In people with a low risk for obstructive sleep apnea and a BMI of 18.5 to 24.99, which is considered optimal, there was a four-time greater risk of stroke symptoms in participants who had fewer than six hours of sleep per night, compared to participants in the same BMI range who got seven to eight hours of sleep per night. The study found no association between short sleep periods and stroke symptoms among overweight and obese participants.

“We adjusted for many possible factors that could explain this increase, including hypertension, high cholesterol, sleep disordered breathing and being overweight or obese,” explains Megan Ruiter, Ph.D., the study’s lead author and a UAB post-doctoral fellow in the Division of Preventive Medicine in the School of Medicine.

“Despite controlling for other known stroke risk factors, we still found the association between sleeping less than six hours and reporting stroke symptoms, like sudden body weakness or numbness or deficits in vision,” says Ruiter. “These participants may be late in the development of a stroke. It is possible they may have had a stroke but it was not verified with a physician.”

Sleep specialist Susan Harding, M.D., who was not involved with this study, says these findings do not surprise her.

“Short sleep duration is already associated with cardiovascular death and other cardiovascular related events,” says Harding, director of UAB’s Sleep/Wake Disorders Center. “What is different with this study is that it specifically looked at people who are at a normal weight, which means they are less likely to have diabetes — which is a stroke risk factor — and found they are still at increased risk of stroke symptoms.”

The study also found a differential risk according to racial group.

“We find that sleep duration might partially explain the relationship between ethnic differences in stroke symptoms,” Ruiter adds. “African-Americans had a greater prevalence of short sleep, and they were more likely to have stroke symptoms.”

Ruiter notes that sleep duration was self-reported by participants, making it a limitation of the study, as recall accuracy can vary.

“We need to see if sleep duration is related to actual stroke events. It would be great to learn more about what it is about sleep duration. Is it actually sleep fragmentation, or perhaps the perception of your sleep and the factors that contribute to its quality rather than sleep duration itself? These are all really important factors that are modifiable through behavioral treatment,” says Ruiter.

Data used for this study comes from the Reasons for Geographic and Racial Differences in Stroke study, led by George Howard, DrPH, of the UAB School of Public Health. REGARDS enrolled 30,239 people ages 45 and older between January 2003 and October 2007, and it continues to follow them for health changes. The study is funded by the National Institute of Neurological Disorders and Stroke.

http://www.uab.edu/news/latest/item/2483-sleep-debt-hikes-risk-of-stroke-symptoms-despite-healthy-bmi

A simple jogging test in middle age predicts risk of heart attack and stroke.

On By A.P.In Exercise, Health, Heart Attack, StrokeLeave a comment

Researchers at Ut Southwestern Medical Center in Dallas have found that how fast a middle-aged man can run a mile may determine his risk of heart attack or stroke over the next 10 years.

For the study, researchers collected information from 11,000 men who underwent a clinical exam and a treadmill exercise test at Cooper Clinic in Dallas between 1970 and 1990.

They found that 1,106 of them died of heart attack or stroke before 2006. After analysing the data they were able to predict a man’s risk of developing heart disease based on his running time.

The study found a 55-year-old man who took 15 minutes to run a mile had a 30% lifetime risk of dying from heart disease. In contrast , a 55-year-old who could run a mile in eight minutes had a risk of less than 10%.

The researchers found that a higher fitness level lowered the lifetime risk of heart disease even in people with other risk factors in their study.

http://timesofindia.indiatimes.com/home/science/Simple-jogging-test-may-reveal-risk-of-heart-attack/articleshow/8480784.cms

http://www.utsouthwestern.edu/utsw/cda/dept353744/files/639605.html