With faux sugars, real suspicion - Americans love sweeteners but can't shake their distrust of the stuff. The science can confuse.

What is it about artificial sweeteners?

As never before, they pervade the American diet -- in pink, yellow and blue packets on diner counters, in sugar-free cookies and diet juices, in sodas and smoothies and low-calorie yogurt and boxes of powder for baking.

And, as ever, many Americans view them with suspicion.

Every few years, a study links one to cancer. People get scared. Follow-up research finds nothing to worry about. Decades may pass, but sooner or later another scary study comes along. And still, we keep eating these faux sugars.

Today, nearly 200 million Americans consume sugar-free or low-calorie products, according to the Calorie Control Council, a group that represents the diet food industry. About half of those people consume an average of four of these products every day.

Diet sodas make up 29% of the nation's $200-million annual soft drink sales, and the percentage is rising, says John Sicher, editor and publisher of the trade journal Beverage Digest.

That we're consuming artificial sweeteners is clear. Whether we'll ever do so with total ease is not. Suspicions about the safety of man-made sweeteners started soon after saccharin was invented more than a century ago. Studies, later disputed, led to warning labels on one sweetening product, the banning of another, intermittent mistrust of others.

The most recent volley in the sweetener wars came from researchers in Italy who say aspartame causes cancer in rats. Similar fears have been levied about newer sweeteners, including sucralose, commonly known as Splenda.

Supporters and critics of the substances each criticize the methods and motives of the other side. Many food chemists say it is impossible for people to eat or drink enough of any man-made sweetener to cause health problems.

Sweetener skeptics, on the other hand, say that safety studies are often funded with industry dollars and there aren't enough data to be sure about the safety of most artificial sweeteners.

Behind the seemingly endless cycles of debate, there may be something cultural at work in the way we think about what we eat, says USC sociologist Barry Glassner, author of "The Gospel of Food," which urges people to abandon food fads in favor of calmer attitudes toward eating.

A few generations ago, Glassner says, people looked to science and technology as salvation -- it was the time of Kool-Aid, Tupperware and pasteurized processed cheese.