The Food and Drug Administration is re-evaluating its definition of what counts as a "healthy" food.

The change comes as healthful fats — including fats found in nuts — are increasingly recognized as part of a good diet.

Currently, if a food company wants to put a "healthy" claim on its label, regulations stipulate that it must be very low in fat. The specific rules are complex, but, for instance, a snack food can contain no more than 3 grams of fat for a regular-size serving.

This means that many snacks that include nuts don't qualify as healthy.

The FDA says that in light of evolving nutrition research, it is now planning to solicit public and expert comment to come up with a new definition that will help consumers make informed choices.

The move comes after the maker of Kind brand bars — which contain almonds and other nuts — pushed back against an FDA complaint about its use of the phrase "healthy and tasty." After making its complaint, the FDA now says that after reviewing the situation, it is comfortable with the company using the phrase.

"We are pleased that the FDA is looking into" revising its definition, says Daniel Lubetzky, the CEO of Kind bars. The company helped launch a citizens' petition requesting that the FDA take action.

The FDA definition of healthy is a holdover from the era when dietary fat was vilified.

"Low in fat used to mean healthy," says Thomas Sherman, an associate professor at Georgetown University who teaches medical students about nutrition. "And high in fat had a pejorative context to it."

As we've reported, millions of Americans clung to the advice that low fat was best. During the 1990s, an era of fat-free mania, Americans were making a habit of munching on sugar-rich, refined-grain products such as Snackwells.

But Sherman says there's been an evolution in understanding — and awareness. We now know that consuming too much sugar can have negative health consequences. And there's a growing awareness that foods "higher" in fat can be healthful.

As we've reported, many new studies affirm the healthfulness of eating more plant-based fats, such as avocados and nuts.

"Nuts have healthy fats ... that we know are good for cardiovascular health and mental health and are good sources of protein," says Sherman. He points out that nuts are calorie-dense, so people should limit portion sizes. But he says that overall, "nuts are a wonderful component of our diet."

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