Quite the contrary, say researchers at the State University of New York at Albany. Based upon studies of yawning in college students, they contend this somewhat involuntary act is actually an ancient, hard-wired ritual that evolved to help earlier humans stay alert to possible danger.
In one of the experiments, they asked half of the volunteers to either breathe normally or through their mouths while watching the videos; the other half were told to breathe only through their noses. Among the first group, half exhibited contagious yawning; none of the nose breathers did.
In a second experiment, subjects held either a cold or warm pack to their forehead while watching the videos. Like the nose breathers, the cold pack group did not yawn while the warm packers yawned at normal rates.
From these experiments, the researchers concluded that yawning is an attempt to cool the brain, which like a computer works less efficiently as it heats up. Yawning enhances brain function, they say, by increasing blood flow to the brain and drawing in cooler air, as does breathing through the nose or cooling the forehead.
So rather than promoting sleep, the researchers contend that yawning helps mitigate the need for it. And when it becomes contagious, it's an evolutionary adaptation to promote group vigilance.
AIDSTruth.org or www.aidstruth.org
An antidote to continuing denial (in some places) that HIV is the cause of AIDS, this Web site presents scientific evidence and explains the benefits and risks of antiretroviral drugs. Created by research scientists and activists.
STORIES FOR THE WAITING ROOM
In 2004, an overweight woman read in the tabloid Weekly World News (typical headline: Bat-boy born to Duluth couple!) that ingesting tapeworms was a foolproof way to lose weight. It's like having your "own little diet coach deep down inside," the paper reported.
So the woman ate several undercooked pork tacos and was successfully infected by the Taenia solium parasite, a kind of tapeworm that is found in contaminated pork and which causes severe pain, paralysis, vision loss and worse.
A few months later, the woman died.
OBSERVATION
Health nuts are going to feel stupid someday, lying in hospitals dying of nothing.
- Comedian Redd Foxx, who died of a heart attack in 1991 on the set of the TV sitcom "The Royal Family"
BODY OF KNOWLEDGE
There are 450 hairs in an average eyebrow.
GET ME THAT. STAT!
More than 1 in 5 adults 20 to 49 years of age have tried cocaine or other street drugs at some time in their life, according to the Centers for Disease Control's National Center for Health Statistics.
NEVER SAY DIET
The world speed record for eating cow brains is 17.7 pounds in 15 minutes, held by Takeru Kobayashi.
PHOBIA OF THE WEEK
Genuphobia - fear of knees
If this is dying, then I don't think much of it.
- English author Lytton Strachey (1880-1932)
SHRINK AB FAT
It'll take a dynamic duo to shrink your waist. Combining diet and exercise is the only way to reduce abdominal fat cells, researchers at Wake Forest University say. They asked 45 obese women to start a diet, and two-thirds of them also walked three times a week. After 20 weeks, everyone had lost about 25 pounds, but the walkers also reduced the size of their tummy fat cells by 19%. The diet-only women had no such change.
BLOOD PRESSURE AND HEART DISEASE
Lowering blood pressure could help reverse heart disease for many people. Cleveland Clinic measured arterial plaque in nearly 300 adults with heart disease. After two years, arteries in those with high blood pressure (140/90 or greater) had become even more clogged. But those whose pressure came in at 119/79 or lower decreased the amount of gunk in their arteries. Lowering blood pressure can be as easy as regular walks, limiting sodium and alcohol and eating lots of fruits and veggies.
