A growing number of Americans seem to believe that everything is better with butter.

"I love butter," says Ashleigh Armstrong, 29, as she sips coffee at a cafe in Washington, D.C.'s Union Station. Among her favorites: "Anything from Julia Child's cookbooks."

There's no margarine in Ashleigh's refrigerator. "I'm not going to have the fake stuff," she says, adding that she'd rather indulge a little in rich foods and burn it off at a spinning class.

And no, she's not worried about cholesterol. That's her grandmother's generation's concern, she says.

Ashleigh's butter habit represents a paradigm shift in the U.S. that's been taking place gradually.

"Americans are eating more butter. There's no question about it," says Harry Balzer of the NPD Group, a marketing research firm that tracks Americans' eating habits.

He says that back in the mid-1990s, only about 30 percent of households he surveyed were cooking with butter or spreading it on their morning toast. Most families were eating margarine.

"The increase in butter consumption in America coincides with the decline in margarine consumption," Balzer says.

Two decades ago, more than 80 percent of households reported consuming margarine. But as that figure has dropped to about half of households, butter consumption has grown about 40 percent.

"It's a significant change," Balzer says.

So what might explain this shift? Well, for many years Americans had been hearing the message to avoid animal fats to protect our hearts. Cholesterol was the nutritional bogeyman. And margarine is cholesterol-free.

Back in 1992, 44 percent of cooks in the households Balzer surveyed said they were concerned about the amount of cholesterol in their food. "Today, that number is 27 percent. It's dropped quite a bit," Balzer says.

And this is likely because the science of fat has evolved.

First, there was the revelation that trans fats,found in many margarine spreads back in the 1990s and early 2000s, were really bad for us. Then add the new evidence that eating some animal fat is not so bad. There's also a growing movement toward clean, less processed foods.

Now, you might assume that the rebound could explain the predictions by some that the U.S. is close to a butter shortage. But as we reported earlier this week, this isn't really the case. Inventory of American-made butter is low because of the appetites of butter lovers in other countries, including Egypt and Morocco. Exports are way up.

"Since the early 2000s we've basically gone from zero exports of butter to where it's 10 or 11 percent of our market. That's an incredible growth rate," says dairy economist Brian Gould of the University of Wisconsin.

As for the stories making the rounds on the Internet about adding spoonfuls of butter to your tea or coffee, well, that sounds like a bit much, even to butter-lover Ashleigh Armstrong and her partner, Simon Anderfuhren, who is French.

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