Quotes of the Day

The Katie Couric Effect
When NBC television personality Katie Couric underwent a colonoscopy live on national TV in March 2000, she did more than show the world the insides of her bowels. Couric, whose husband died from colon cancer at age 42, also significantly raised the rate at which Americans signed up for a colon-cancer screening. In a study that appears in the current issue of the Archives of Internal Medicine, a team of researchers from Michigan and Iowa reports that colonoscopy rates across the U.S. jumped more than 20% following Couric's examination.

And that may translate into saved lives. More than 130,000 Americans this year will be found to have colon cancer, and more than 56,000 will die from the disease, making it the second leading cause of cancer deaths, according to the National Cancer Institute. Many of these deaths could have been avoided if people were not so squeamish about undergoing colonoscopy, which is what makes the "Katie Couric effect," as researchers have dubbed it, so important. --By David Bjerklie

Depression: The Blues Gene
Jack and Joe both lose their jobs and their girlfriends. Rotten luck. Then their 401(k)s tank, and their dogs get run over. Argh. But while Jack spirals into despair, Joe takes his losses and eventually bounces back. How do you explain the difference? Depression may seem to be a matter of who's made of sterner stuff, but a new study shows that genes play an important role. Researchers have found that individuals with the short version of a particular gene involved in the production of a key brain chemical are more than twice as likely to get depressed in the aftermath of a stressful event than those with the long, more depression-protective version. While the exact causes of depression remain difficult to unravel, this finding is further evidence that the disease is best explained not by genes or circumstances alone but by the interaction of the two. --By David Bjerklie

Belly And Brain
Because folks with Alzheimer's tend to waste away, obesity is not something we associate with the disease. But a new study shows that women who are overweight in their 70s have a significantly higher risk of developing the brain disorder by their late 80s — the first strong evidence to link the obesity epidemic to the growing incidence of Alzheimer's. It's also a good reason to stay trim. A 5-ft. 4in. woman who weighs 145 lbs. increases her Alzheimer's risk 36% with every 7 lbs. she gains. -- By Sanjay Gupta, M.D.

• David Bjerklie; Sanjay Gupta, M.D.