Here is a brief look at some of the top health headlines this week:

-Antidepressant prescription rates are on the rise – they’re now prescribed more often than drugs for blood pressure, asthma, or high cholesterol.

-Teens in Canada are smoking less, both males and females with teenage girls leading the way.  Great news from up North!

-According to a study by the National Health and Social Life Survey, the U.S. circumcision rate peaked at nearly 90 percent in the early 1960s but began dropping in the ’70s. By 2004, the most recent year for which government figures are available, about 57 percent of all male newborns delivered in hospitals were circumcised. In some states, the rate is well below 50 percent.  It is thought that rates are still dropping and may be as low as 46% as a national average.

-For those of you that always thought women are way more chatty than guys;  researchers placed microphones on 396 college students for periods ranging from two to 10 days, sampled their conversations and calculated how many words they used in the course of a day.  The score: Women, 16,215. Men, 15,669.   Now that is truly a surprise, maybe it has something to do with men getting better at expressing themselves?

People who are often stressed out or depressed are far more likely to develop memory problems than those with more happy dispositions, U.S. researchers said on Monday in a finding that sheds light on early predictors of Alzheimer’s disease.

They said those who most often are anxious or depressed were 40 times more likely to develop mild cognitive impairment, a form of memory loss that is often a transitional stage between normal aging and dementia.

Researchers analyzed data from two large studies involving 1,256 older people who started the studies with no memory problems.  After up to 12 years of follow up, 482 people in the study developed mild cognitive impairment. Participants were rated on how prone they are to worry and depression.

“What we’re measuring is a personality trait that we all have to greater or lesser degree. We all experience anxiety and periodic depression. This trait helps identify people for whom that is more characteristic than others,” said Wilson, whose study appears in this week’s issue of the journal Neurology.

“This isn’t a measure of stress, but of the response to stress,” he said.

The latest research suggests that chronic stress may harm parts of the brain responsible for responding to stress — an area that is also associated with memory, he said.  So now all you depressed folks have another reason to be stressed out and depressed.

Remeber those fat burning jiggle machines of the 1950’s?  Well they seem to be coming back into style.  Even NASA is testing the concept.

These machines use vibrations to tone muscle and claim to do it faster. Aggressive promoters also say the equipment improves flexibility and strength, reduces pain and stress, builds muscle and reverses osteoporosis. 

However, researchers warn of possible injuries ranging from back pain to cartilage damage. One even warns that the high-powered jiggling might harm the brain. They say the science is thin and too little is known about the long-term effects of such powerful vibrations.

Still, NASA is studying vibration as a possible tool for reducing muscle atrophy and bone loss during astronauts’ long, weightless trips in space.

And users of the equipment love the sensation and the quick workout. Workout times are reduced by two-thirds, advocates say, a claim that appeals to busy professionals, mothers of young children and just about anyone who shuns exercise.

“I feel kind of tingly and a little like I got off a ship, kind of shaky but in a good way,” said Amy Allen, a 40-year-old working mom in Chicago, after a 25-minute workout on the Power Plate, one of the higher-end brands. “I’m hoping this is the solution to help me get that extra weight off.”

The Power Plate vibrates 20 to 50 times a second in three directions, increasing g-forces on the body, and according to the Northbrook, Ill.-based company of the same name. The company says that raises the effectiveness of lunges, squats and other exercises done while standing on it.  So go-ahead and shake a leg and get fit.