Researchers at the University of Missouri took a close look at 2 successful ways to lose weight - the Weight Watchers program, and joining a gym.
What they found provides some food for thought.
After 3 months, Weight Watchers participants dropped about 5 per cent of their body weight.
But they also lost some lean muscle mass, and didn't change their percentage of body fat.
Steve Ball, and professor of exercise science, says, "Lean tissue is directly correlated to metabolism. As this tissue goes down, our metabolism slows down, so it makes it more difficult to lose more weight later on."
But, Professor Ball says Weight Watchers participants were better at sticking with their regimen.
Ball says, "One of the pros of the Weight Watchers group is we a very low dropout rate. In the fitness center group, we had about a double dropout rate."
Ball says Weight Watchers might be able to build on its success by emphasizing exercise more.
Could cardiac pacemakers be hacked by computer wizards?
Computer security researchers say they have done it.
But, a heart expert at Cooper University Hospital says the hundreds of thousands of people with those life-saving devices have nothing to worry about.
Dr. John Andriulli says it took $30,000, and a major effort by the researchers to gain wireless access to one pacemaker in the lab.
Dr. Andriulli told us, "To have the knowledge, the technology and the background to accomplish that makes it almost impossible."
The doctor says the many varieties of pacemakers in use complicates any hacker's efforts.
And they don't have personal data.
He says, "There is no actual medical history in the computer itself."
The government also believes the devices are very secure.