Investors are taking a big bite of Wendy's Co. (WEN) stock as Americans appear to be chowing down on cheap fast food again.

The strong results from McDonald's, Burger King and Wendy's may have less to do with their burgers and more with their chicken offerings. All three fast-food chains introduced new chicken sandwiches this year. There is Wendy's Fresh Mozzarella Chicken Sandwich, Burger King's Chicken Parmesan Sandwich and McDonald's line of new Signature Crafted Sandwiches that includes a Sriracha, Sweet BBQ Bacon and Pico Guacamole chicken sandwich.

Before the market open on Wednesday, Aug. 9, the burger chain reported second-quarter earnings rose 50% to 15 cents a share, while same-store sales spiked 3.2% in North America, compared to a meager 0.4% increase in the year-ago period. Wendy's revenue decreased 16.3% to $320.3 million due to the company having 251 fewer owned restaurants in the three months through July 2 compared to last year.

Shares of Wendy's finished up 3.88% on the session.

Interestingly, Wendy's was not the only fast-food burger joint to do well this quarter. McDonald's Corp. (MCD) reported a blowout second quarter late last month, posting a 3.9% same-store sales growth in the U.S. Then, on Aug. 2, Restaurant Brands Int.'l Inc. (QSR) reported that revenue at Burger King increased 4.7% and its same-store sales rose 3.9% in the second quarter.

Meanwhile, on Aug. 3, Shake Shack Inc. (SHAK) , a pricier, newer and more casual-dining-style burger eatery, reported a same-store sales decline of 1.8% for the second quarter.

As it turns out, Shake Shack has just one chicken sandwich on its menu, the Chick'n Shack, which was introduced early last year. In a recent research note, Barclays analyst Jeffrey Bernstein pointed out that Shake Shack's sales were particularly pressured in May and June, when Scott said there was an increased demand for chicken. Bernstein could not be reached for further comment.

College students eating at a McDonald's restaurant.
College students eating at a McDonald's restaurant.

But chicken seems to be where it's at for a lot of Americans.

In recent research notes, Stephens analyst Will Slabaugh said Burger King's Crispy Chicken Sandwich was a "meaningful contributor" to its strong results and that McDonald's solid quarter can be attributed largely to its Signature Crafted menu items, which, in addition to chicken sandwiches, also includes a line of burgers made with 100% fresh beef. Slabaugh declined to comment further on Wednesday.

The National Chicken Council, citing results from a survey conducted this June, reported in July that 67% of consumers said they ate a chicken meal or snack outside their home in the two weeks leading up to the survey. And although that consumption was down 6.9% from last year, the council said "consumers' taste for chicken shows no signs of waning," with 21% of people surveyed expect to eat more chicken over the next 12 months.

"The U.S. Department of Agriculture projects Americans will eat close to 92 pounds of chicken per person this year, breaking last year's record of 91 pounds," said the National Chicken Council spokesman Tom Super in a statement. "Although consumers' self-reported consumption is down slightly in the survey, the data show that chicken is still top of mind for consumers."

In 2016, beef consumption in the U.S. slightly increased to 55.6 pounds per person, on average, from the previous year. But, according to National Resources Defense Council research, Americans ate 19% less beef from 2005 to 2014.

As Jeremy Scott, Mizuho proteins and restaurant analyst, told TheStreet in a recent interview, there was an unusual heightened U.S. consumer demand for chicken, wings in particular, in April and May that has remained strong this summer. The demand and low production of chickens have led to a 40% rise in July of wholesale chicken wing prices.

"It's very, very sticky," Scott said at the time, estimating that wholesale wing prices will be high for the next six months. Scott was unavailable for further comment.

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