Tuesday, July 29, 2014

Research Backs a Traditional Balm: Nature

English: unidentified plant in Singapore Botan...
English: unidentified plant in Singapore Botanical Garden (Photo credit: Wikipedia)
Dawn crepuscule in the Singapore Botanical Gardens
Dawn crepuscule in the Singapore Botanical Gardens (Photo credit: Wikipedia)
orchid (Singapore botanical gardens)
orchid (Singapore botanical gardens) (Photo credit: Wikipedia)
Singapore Botanical gardens
Singapore Botanical gardens (Photo credit: j0055)
Singapore Botanical Garden
Singapore Botanical Garden (Photo credit: Wikipedia)
July 29, 2014

And as if to say, health can't be bought, nature comes to the rescue - abundant, free, natural... and it just doesn't soothe tired eyes, but green, leafy scenery soothe tired brains as well...

by Gretchen Reynolds

Scientists have known for some time that the human brain's ability to stay calm and focused is limited and can be overwhelmed by the noise and hectic demands of city living, sometimes resulting in a condition informally known as brain fatigue. With brain fatigue, you are easily distracted, forgetful and mentally flighty.

But a new study from Scotland suggests you can ease brain fatigue by simply strolling through a leafy park.

Researchers have long theorized that green spaces are calming, requiring less of our directed mental attention that urban streets do. Instead, natural settings invoke "soft fascination," a term for quiet contemplation, during which the brain can reset overstretched resources of attention and reduce mental fatigue.

But this theory has been difficult to put to the test. Previous studies have found that people who live near trees and parks have lower levels of cortisol, a stress hormone, in their saliva than whose who live primarily amid concrete, and that children with attention deficits tend to concentrate and perform better on cognitive tests after walking through parks. Scientists have studied volunteers and found that brain wave readouts show that the volunteers are more calm when they view natural scenes.

But it had not been possible to study the brains of people while they were actually outside until the recent development of a lightweight, portable version of the electroencephalogram, a technology that studies brain wave patterns.

For the new study, published in March in The British Journal of Sports Medicine, researchers at Heriot-Watt University in Edinburgh and the University of Edinburgh attached these new, portable EEGs to the scalps of 12 healthy young adults. The electrodes sent brain wave readings wirelessly to a laptop carried in a backpack by each volunteer.

Essential body renewal

The researchers then sent the participants on a short walk throguh Edinburgh, first through a historic district, then through a parklike setting and finally through a commercial district. Afterward, the researchers looked for wave patterns that they felt were related to measures of frustration, directed attention, mental arousal and meditativeness or calm. What they found confirmed the idea that green spaces lessen brain fatigue: in the commercial area their brain waves were aroused; in the park the readings became more meditative.

The study was small, more of a trial study of the new EEG technology than a definitive examination of the cognitive effects of seeing green.

But even so, said Jenny Roe, a lecturer at Heriot-Watt who oversaw the study, the findings were consistent, strong and valuable. The study suggests that, right about now, you should consider "taking a break from work," Dr. Roe said, and "going for a walk in a green space or just sitting, or even viewing green spaces from your office window." This is not a waste of time, Dr. Roe said. "It is likely to have a restorative effect and help with attention fatigue and stress recovery."

Taken from TODAY Saturday Edition, 13-April-2013

Monday, July 21, 2014

Minimalist Sneakers Can Cause Injuries, Too

English: Vibram FiveFingers Bikila shoes, top ...
English: Vibram FiveFingers Bikila shoes, top view. (Photo credit: Wikipedia)

by Gretchen Reynolds

When Dr. Douglas Brown, a radiologist in Orem, Utah, noticed an uptick recently in the number of barefoot runners he was seeing with heel and foot problems, he wondered if there might be a connection between their unshod training and their sore feet. But he couldn't find any scientific studies that had examined the issue.

So he approached Sarah Ridge, a professor of exercise science at Brigham Young University in Provo, Utah, who studies impact injuries in sports, and suggested she undertake one.

The resulting study, published in Medicine & Science in Sports & Exercise, will probably add fuel to the debate about the benefits of running barefoot or wearing minimalist "barefoot" shoes. Does the barefoot style reduce a runner's risk of pain and injury (as enthusiasts believe)? Or does barefoot running simply contribute to the development of a different set of injuries in some runners?

To find out, Dr. Ridge began by recruiting 36 experienced runners, men and women, who, until then, had run between 25 and 50 kilometers a week while wearing normal running shoes. She sent them to Dr. Brown for baseline M.R.I. scans of their feet and lower legs to check for any injuries or problems.

Those who believe in barefoot running often point out that humans ran and walked without shoes for millenniums before footwear was invented. They argue that being unshod is normal for humans and should reverse past injuries related to modern running shoes and prevent future ones.

But anecdotal evidence from physicians who treat runners indicates that some people who take up barefoot running develop entirely new aches and injuries.

Dr. Ridge's volunteers all started the study with normal feet and lower legs, according to their M.R.I. scans, which were read by multiple radiologists.

Half of the group members were randomly assigned to continue running as they had: same distance, same shoes.

The other runners were given a pair of Vibram Five Fingers barefoot-style shoes and asked to increasingly incorporate some barefoot-like distance distance into their runs, but gradually.

After 10 weeks, both groups of runners received a follow-up M.R.I. There was no evidence of injuries to or changes in the tissues of the lower leg, like the Achilles's tendon, in any of the runners. But more than half of the runners wearing the minimalist shoes now showed early signs of bone injuries in their feet.

Natural way to repair bone damage?

Most had developed bone marrow edema, an accumulation of fluid, similar to what happens during bruising, in their foot bones. Two even had full stress fractures, one in her heel bone and one in his metatarsal, one of the long foot bones.

Almost all of the runners in the minimalist shoe group were spontaneously running fewer kilometers at the end of the 10 weeks than they had been at the start, "probably," Dr. Ridge said, "because their feet hurt."

Why some of the barefoot-style runners developed serious foot problems and others did not is not yet clear, but Dr. Ridge is now analyzing additional data about the volunteers, which includes information about each runner's mileage, running form, body weight and other variables.

"What we hope to see is whether there are some runners who, because of their biomechanics or other factors" seem to be particularly predisposed to foot injuries during the transition to barefoot-style running and perhaps shouldn't make the switch at all from normal running shoes, she said.

The results don't mean that everyone who chooses to switch to minimal or no footwear will court foot injury, Dr. Ridge said. "But I would tell anyone who wants to try" kicking off their normal shoes, "to be extremely cautious during the transition period." Increase your use of minimal wear slowly.

Barefoot-style running may have been natural for our ancestors, Dr. Ridge points out, but it's a new experience for most of our feet.

Taken from TODAY Saturday Edition, April 13, 2013

Saturday, July 19, 2014

The Inner Processes Of Eating

English: diagram of action of swallowing a bol...
English: diagram of action of swallowing a bolus of food (Photo credit: Wikipedia)

by Mary Roach

WAGENINGEN, the Netherlands - In Food Valley, a cluster of universities and research facilities, nearly 15,000 scientists are dedicated to improving - or, depending on your sentiments about processed food, compromising - the quality of our meals.

Here I am, in the Restaurant of the Future, a cafeteria at Wageningen University where hidden cameras record diners as they make decisions about what to eat. And here is a bowl of rubbery white cubes the size of salad croutons. Dr. Andries van der Bilt has brought them from his lab at the nearby University Medical Center Utrecht.

"You chew them," he said.

An oral physiologist, Dr. Van der Bilt uses the cubes to quantify "masticatory performance" - how effectively a person chews.

He and his colleagues study the mouth's role as the human food processor.

Chewing is as unique and consistent as the way you walk. There are fast chewers and slow chewers. Some of us chew straight up and down, and others chew side-to-side, like cows.

Dr. Van der Bilt studies the neuromuscular elements of chewing. You often hear about the impressive power of the jaw muscles. In terms of pressure per single burst of activity, these are the strongest muscles we have. But it is the jaw's nuanced ability to protect that fascinates Dr. Van der Bilt.

Think of a peanut between two molars, about to be crushed. At the precise millisecond the nut succumbs, the jaw muscles sense the yielding and let up. Without that reflex, the molars would continue to hurtle reckelessly toward one another.

To keep your jaw muscles from smashing your teeth, the body evolved an automated braking system. The faster and more recklessly you close your mouth, the less force the muscles are willing to apply. Without your giving it a conscious thought.

The study of oral processing is about the entire "oral device" - teeth, tongue, lips, cheeks, saliva, all working together toward a singular revolting goal, bolus formation.

"Bolus," here, refers to a mass of chewed, saliva-moistened food particles - food that is in, as one researcher puts it, "the swallowable state."

Bolus formation and swallowing depend on a highly coordinated sequence of neuromuscular events and reflexes, researchers have found. The larynx (voice box) usually blocks the entrance to the esophagus. When food or drink is ready to be swallowed, the larynx has to rise out of the way, both to allow access to the esophagus and to close off the windpipe and prevent the food from "going down the wrong way."

To allow this to happen, the bolus is held momentarily at the back of the tongue, a sort of anatomical metering light. If the larynx doesn't move quickly enough, the food can head down the windpipe instead.

A more more entertaining swallowing missteps is nasal regurgiration. Here the soft palate fails to seal the opening to the nasal cavity. This leaves milk or chewed peas in peril of being expelled through the nostrils. Nasal regurgiration is more common with children, because they often laugh while eating and because their swallowing mechanism isn't fully developed.

"Immature swallowing coordination" is the reason 90 percent of food-related choking deaths befall children under 5. Also contributing: immature dentition. Children grow incisors before they have molars; for a brief span of time, they can bite off pieces of food but cannot chew them.

Round foods are particularly treacherous because they match the shape of the trachea. If a grape goes down the wrong way, it blocks the tube so completely that no breath can be drawn around it. Hot dogs, grapes and round candies take the top three slots in a list of killer foods published in the July 2008 issue of The International Journal of Pediatric Otorhinolaryngology.

Those who can chew want to chew. We especially enjoy the crunch. A colleague of Dr. Van der Bilt, Dr. Ton van Vliet, has spent seven years figuring out how crunch works.

"It's all bubbles and beams," he said, sketching networks of water-filled cells and cell walls. When you bite into an apple, the flesh deforms and at a certain moment the cull walls burst. And there is your crunch. In crispy snack foods, the bubbles are filled with air. As a piece of produce begins to decay, the cell walls break down and water leaks out. Now nothing bursts.

For a food to make an audible noise when it breaks, there must be what's called a brittle fracture: a sudden, high-speed crack. Dr. Van Vliet takes a puffed cassava chip from a bag and snaps it into two.

"To get this noise, you need crack speed of 300 meters per second," he said. The speed of sound. The crunch of a chip is a tiny sonic boom inside your mouth.

Crispiness and crunchiness appeal to us because they signal freshness, Dr. Van Vliet said. Old, rotting, mushy produce can make you ill. "You eat physical properties with a little bit of taste and aroma," Dr. Van Vliet said. "And if the physics is not good, then you don't eat it."

Mary Roach is the author of the new book "Gulp: Adventures on the Alimentary Canal," from which this article is excerpted.

Taken from TODAY Saturday Edition, 06-April-2013

Coffee: Much More Than Just Caffeine

A Sip of Turkish Coffee
A Sip of Turkish Coffee (Photo credit: Kuzeytac)

by Sindya N. Bhanoo

People who live on the Greek island of Ikaria are known to have remarkably high life expectancies, and researchers have been studying them carefully to learn why. Now a new report suggests that one reason may be the coffee they drink.

"This boiled coffee seems to generate antioxidant substances," said Dr. Gerasimos Siasos, a professor at the University of Athens Medical School and an author of the study, which appears in the journal Vascular Medicine.

He and his colleagues found that older islanders who drank the boiled coffee had better functioning endotheliums - the layer of cells that line blood vessels.

"When there is dysfunction here, the arteries become more stiff, and we have heart attacks and arterial occlusions," said Dr. Siasos, who did the research with a colleague.

Coffee is only one factor. "It has to do with their way of living," Dr. Siasos said. "People sleep over eight hours a night, there is increased socializing, and they have much less stress than people in Athens."

The islanders also eat a Mediterranean diet that includes many fruits, vegetables, olive oil and fish. Most also nap every day and walk and garden regularly, Dr. Siasos said.

The researchers will journey to Ikaria this summer to study how the island's water, minerals and air quality might also be contributing to longevity.

Taken from TODAY Saturday Edition, 06-April-2013

Thursday, July 17, 2014

Aspirin May Lessen Risk of Skin Cancer

Generic regular strength enteric coated 325mg ...
Generic regular strength enteric coated 325mg aspirin tablets, distributed by Target Corporation. The orange tablets are imprinted in black with "L429". (Photo credit: Wikipedia)

by Nicholas Bakalar

Researchers report that a woman's regular use of aspirin may decrease her risk of melanoma, the most serious kind of skin cancer.

The study, published online in the journal Cancer, included 59,806 women ages 50 to 79. Researchers gathered health and lifestyle data at the start of the study, and the women reported their health in yearly questionnaires over an average 12 years of follow-up. The women brought in their medicine bottles for the researchers to examine and record.

There were 548 incidents of melanoma during the period. After controlling for sun exposure, sunscreen use, a history of skin cancer and many other factors, the researchers found that women who reported using aspirin had an average 21 percent lower risk of melanoma compared with nonusers, and the longer they used aspirin, the lower their risk.

Natural protection against the sun's rays

The reasons for the effect are unclear, but the authors suggest that aspirin's known effect in promoting cell death and activating tumor suppressor genes may be factors.

The senior author, Dr. Jean Y. Tang, an assistant professor of dermatology at Stanford University in California, said the study was observational, not a clinical trial, and that correlation does not equal causation.

"It's an important finding for high-risk women to discuss with their doctors," Dr. Tang said, adding, "but it's way too early to recommend that everyone go take aspirin to prevent melanoma."

Lifted from TODAY Saturday Edition, April 6, 2013