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The American diet hasn’t changed in years — except for this one thing


Despite a slew of new studies, recommendations and nutrition fads ranging from gluten-free to paleo, the general American diet has not changed substantially since 2000, recent government data shows.

Between 2000 and 2010, the most recent year for which complete data is available, the average American’s daily caloric intake declined by a mere 2 percent. And the number of calories we get from each food group also has stayed largely constant.

But one type of food has seen a huge change: The number of calories that the average American got from nuts jumped by 25 percent. And the amount of nuts that Americans consume has continued climbing.

The findings, which were published as part of a Department of Agriculture analysis this month, derive from a data set called the Food Availability Data System. Instead of asking consumers what they eat after the fact, as nutrition surveys frequently do, FADS tracks the movement of agricultural commodities through the food system, adjusting for waste and providing a better long-term picture of the foods that Americans consume.

That picture suggests that the broad food groups that make up our diet — dairy, vegetables, grains and so on — have remained relatively stable over time, even as individual foods in those groups have cycled in and out of popularity. (Americans eat more kale and fewer white potatoes now, for instance, than they did at the turn of the century.)

Nuts and seeds are an exception: Their consumption has been increasing slowly since the USDA began tracking it in 1970. In the late 1990s, the pace increased — particularly for almonds, which were eaten at almost twice the rate in 2010 as they were in 2000. Peanuts, America’s most-consumed nut, also saw a smaller, but substantial, uptick.

“Nut consumption has been on the increase since nutrition science about the importance of plant-based protein and the value of good unsaturated fats has evolved,” said Lauren Highfill Williams, a spokesperson for the National Peanut Board, an industry association. In 2014, per capita peanut availability — a proxy for consumption — hit 6.3 pounds per year. That’s up from 5.3 pounds in 2000.

There’s little doubt that America’s new taste for peanuts, almonds and their ilk reflects the changed nutritional consensus on nuts, once considered far too fatty to be part of a healthy diet. A spate of studies in the late 1990s linked nuts to all kinds of positive health outcomes, from lower cholesterol and blood pressure to reduced risk of cardiovascular ailment.

Over the past two decades, in fact, it’s become conventional nutritional wisdom that moderate nut consumption should be encouraged: Currently, the U.S. dietary guidelines recommend that non-vegetarians on a 2000-calorie diet eat 5 servings of nuts and seeds per week. That translates to roughly 9 almonds or two teaspoons of peanut butter per day.

“Crunchy nuts are petite powerhouses of taste and nutrition,” writes the American Heart Association, which has specifically included nuts in its dietary guidelines since 2000.

This study 40 years ago could have reshaped the American diet. But it was never fully published.

And yet, even with the recent increase, most Americans still aren’t meeting that recommendation, government data suggests. In fact, a full 6 in 10 Americans don’t eat any nuts in a given day, according to the Centers for Disease Control and Prevention.

A study published in the Journal of the American Medical Association in June found that changes in nut consumption are highly dependent on both income and education: Between 1999-2000 and 2011-2012, respondents with less than a high school education decreased their nut consumption slightly. High school and college graduates ate proportionately more nuts over time, however. A similar pattern played out among low-income consumers: Those closest to the poverty line ate the least nuts to begin with, and increased their consumption the least over time.

Of course, the National Peanut Board maintains that nuts and legumes should fit into everyone’s diet — and can fit into everyone’s budget, with a little finagling. Peanut butter remains one of the most cost-effective ways for consumers to get their recommended daily dose of nut proteins: In November, it averaged $2.54 per pound. That’s lower than all meats except poultry.

“Consumers turn to peanut butter, in particular, during challenging economic times,” Highfill Williams said. She suggests pairing peanut butter with your next banana or adding chopped peanuts to tossed salads.

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