Fed Up With Dietary Flip-Flops?

Celebrity chef Wolfgang Puck knows more about sauces than science. But he knows a lot about Americans' voracious appetite for medical studies on what, when, and how much to eat.

"You know there are some people who are always on a new trip. They think this is good, and all of a sudden they eat no more pasta," says Puck. "Then they said okay we can't eat red meat, then they said we can only drink the red wine."

Nutritional information has become a smorgasbord of contradictory opinions about healthy eating, reports CBS News correspondent Richard Schlesinger. For instance, coffee has been shown to decrease your risk for Parkinson's disease but increase your risk for osteoporosis. It has been shown to decrease the risk of suicide, but may make you more likely to suffer arthritis. Plus, over the course of little more than 1 year, coffee was shown to both increase and decrease the risk of miscarriage.

"It's clear that studies are fallible," says Dr. Ruth Patterson, a Seattle dietician. Patterson has examined the studies and concludes that Americans are getting confused and fed up. "What they perceive as conflicting messages gives them sort of an excuse to throw up their hands and say, 'I can just eat anything I want. What difference does it make?'"

For years healthy eaters banned butter because of its fat content. They turned to margarine, only to learn it too can cause heart disease. "If you love butter and you gave it up and then you find out that margarine is just as bad, you're mad. You've been betrayed," explains Patterson.

Eggs, once demonized as cholesterol-raising agents, have been allowed back into the healthy diet, if eaten in moderation. Even fat, long considered unhealthy, is now being scientifically rehabilitated.

"There are areas where I'm simply confused at this point in time," confesses Walter Willett, MD, of the Harvard School of Public Heath. Willett has been involved in more than 200 studies on health and nutrition. If he's confused, where does that leave everyone else? Somewhere in the middle, he says. "Science does get it right but often there's a lot of back and forth and confusion in the process."

It's all played out in public by researchers and medical journals anxious to serve people hungry for news. One of the latest studies now says that fiber can cause colon cancer. "The problem is that the newest, latest study often isn't the one that stands the test of time," warns Willett.

From his kitchen, Wolfgang Puck watches all the dietary fads come and go with every new study. He offers his own unscientific advice: "Forget the scientists for one night. In the morning we'll worry about the scientists."

There's one more recommendation from the nutritional experts: While you watch what you're eating, watch what you're reading.
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