Fast food giant McDonald's (MCD 0.05%) recently announced it will release a new breakfast sandwich in April, aptly dubbed the Egg White Delight.

As you might expect, that's the company's fancy name for a whole grain Egg McMuffin, sans egg yolk. When all's said and done, then, McDonald's hopes hungry fast food fans can enjoy their morning knowing they've only consumed 260 calories, compared with the 300 calories they would have otherwise ingested going the classic route.

 

Source: McDonalds.com.

Even so, putting aside the fact that I'm firmly in the camp of folks who love egg yolks and champion their under-appreciated nutritional value, I also can't help but wonder whether a measly 40-calorie difference can really sway the determined minds of hungry consumers with a hankering for Mickey D's in the morning. As a basis for comparison, McDonald's Big Breakfast Platter with Hotcakes -- one of which I just so happened to gleefully snarf down last week in a bit of enjoyable due diligence -- sports a whopping 1,090 calories. Heck, with that in mind, sometimes I'd be surprised if I didn't burn 40 calories with a good resounding sneezing fit.  

Of course, the Egg White Delight is just the latest in McDonald's efforts to bolster its struggling comparable same-store sales, which declined a better-than-expected 1.5% in February, led by a 3.3% drop in the U.S. It's important to note, however, that last February's results were helped by an extra day in the month and, excluding those extra 24 hours, domestic same-store sales would have been flat while overall comparable results would have risen 1.7%. All in all, those encouraging numbers helped shares of McDonald's rise more than 12% year to date, closing at a new 52-week high last Friday.

Healthy competition
Meanwhile, the fast food industry as a whole continues its attempts at winning more business of increasingly health-conscious consumers, including Taco Bell owner Yum! Brands (YUM -0.07%) with its mouth-watering Cantina Bell offerings -- the flavor of which, incidentally, also pleasantly surprised me last week. For its part, Yum! Brands enlisted celebrity chef Lorena Garcia to create the Cantina Bell menu to help the chain to better compete with up-and-coming threats in comparatively healthy fast-casual restaurants like Panera Bread (PNRA) and Chipotle Mexican Grille (CMG 0.19%), whose most recent quarterly same-store sales rose 3.8% and 5.1%, respectively.

In addition, Chipotle is also expanding rapidly and increased its number of locations by nearly 15% last year, including 60 new units built in the fourth quarter alone, bringing its total number of restaurants to 1,410. Even so, the power of McDonald's brand becomes increasingly apparent when we consider that, in 2012, the company not only managed to "reimage" more than 2,400 of its existing locations, but also opened the doors to 1,439 new restaurants worldwide. What's more, for those of you wondering whether the golden arches have saturated the global market, in 2013, McDonald's plans to spend more than $1.6 billion to open an additional 1,500 to 1,600 new locations.

Furthermore, both McDonald's and Yum! Brands are rapidly expanding in Asia, where smaller chains like Panera and Chipotle are virtually nonexistent. In fact, McDonald's opened 256 restaurants in China in 2012 alone, making significant headway toward its goals of having at least 2,000 locations there by the end of this year. Yum! Brands, however, boasts a huge head start with more than 5,000 locations in China, with management recently stating they intend to nearly triple that number to more than 14,000 units over time -- or nearly the same number as McDonald's currently maintains in the United States. Even so, that doesn't mean both Yum! Brands and McDonald's can't coexist in the nation of more than 1.3 billion people as the disposable income of its growing consumer class continues to rise.

Foolish final thoughts
In the end, investors need to remember that our world is absolutely enormous, and they should be encouraged to know McDonald's rock-solid brand gives it the luxury of tweaking its menu offerings from time to time. This flexibility has allowed McDonald's to not only survive, but also thrive in spite of its competition for the better part of the last century.

Despite the recent run-up of its shares, then, we should also keep in mind McDonald's currently trades at a reasonable 18.4 times trailing earnings, which isn't substantially higher than its five-year average P/E ratio of 17. As a result -- and noting Mickey D's sustainable 3.1% dividend yield -- I'm convinced investors won't regret adding this stock to their portfolios if they can continue to maintain a long-term mind-set.