ORLANDO, FLA. — In the United States, the snack market is seeing a seismic shift, said Jared Koerten, senior analyst, Euromonitor International, who gave a state-of-the-industry address at the 2015 SNAXPO conference last week.

“It’s not something that’s happened overnight,” Mr. Koerten said, pointing to Euromonitor research over a six-year period. “Each year, every year, snacks have been consistently and significantly outpacing the growth of staple food products.”

A major standout is savory snacks, which is not only the largest category in the snacking universe but also the third-fastest growing. In the United States, savory snacks’ share of the total packaged food comprises one in every $10 that consumers spend on packaged food, Mr. Koerten noted.

“That’s almost double the global average,” he said. “No other region even comes close to savory snacks than the U.S. market.”

Mr. Koerten pointed to an overall rise in snacking, especially from millennials, as well as increasing on-the-go lifestyles, snacking as meal replacement, and a desire for healthier food options as trends that support the snack food industry.

Consumers who are replacing meals with snacks are looking for high-protein options, according to Euromonitor research.

“Looking at relative growth by category, you can see that many of the most successful categories in the U.S. focus on high protein,” he said. “Snack nuts are hugely popular, and snack bars are also seeing a lot of innovation in high-protein products.”

And while protein is a big winner in snacking, it’s not the only one, Mr. Koerten added. Packaging has become just as important as the product variety, as portability and the trend toward grab-and-go become huge market drivers.

As an example, Mondel?z International, Deerfield, Ill., brought major disruption to the market when it introduced its belVita brand of breakfast biscuits.

“In two years, belVita has became one of the major cookie players by focusing on portability, ease of consumption and snacking as a meal replacement,” Mr. Koerten explained, noting that since launching belVita in the United States, Mondel?z has surpassed or is quickly approaching the size of other major cookie brands.

Packaging and label claims are playing bigger roles than ever as manufacturers position snacks as healthier alternatives. When asked about ingredients in a recent Euromonitor survey, millennial consumers indicated that they look for claims such as no artificial ingredients, reduced- or low-calorie, no trans fats or hydrogenated oils, and no added salt.

Playing to this trend, Kind bars have experienced great success.

“When we talk about a natural, unprocessed snack, Kind fits the bill,” Mr. Koerten noted. “Hold the bar, and you can see exactly what’s in it before you buy it,” he said, describing the brand’s clear packaging. “There’s also a litany of health claims that go along the side of the package that wraps around to the other side.”

Mr. Koerten said Euromonitor projects 2% to 2.5% growth in the snack market, approaching $40 billion by 2019. And although savory snacks are the clear market leader, portability, packaging and opportunities for flavor innovation poise bars for continued growth as well.