Although carbonated soft drinks still dominated the market in 2006, accounting for more than half of all beverage sales by volume, total sales in the category dipped by just over 1 percent during the year.
In contrast, sales of energy drinks shot up by almost 50 percent.
"The liquid refreshment beverage market is being driven by the health and wellness trend," said Michael Bellas, chairman and chief executive officer of the Beverage Marketing Corporation, which published the new report.
"Beverages offering functional benefits are growing two to three times faster than conventional refreshment beverages. As consumers increase their per capita consumption of beverages in these newer segments, they are putting pressure on carbonated soft drinks and juice as well as tap water," he said.
According to the report, the "astronomical growth" of the energy drink category is partly because these products "are more successfully tapping into the spirit of the age, which is characterized by a greater emphasis on functional, healthy products."
Total sales by volume of sports drinks increased by almost 12 percent in 2006, with PepsiCo's Gatorade brand alone revealing the same growth rate. The popular sports beverage displaced Coca-Cola's Sprite, which underwent a 3.5 percent volume reduction, to become the fifth top beverage brand.
In terms of volume share, Coca-Cola's flagship Coca-Cola drink remained top of the list, accounting for almost 16 percent of the market, despite a 2.5 percent reduction in sales from the year earlier. PepsiCo's Pepsi drink held second place, with just over a 10 percent market share, although sales of this beverage also declined by 3.1 percent compared to 2005.
The third leading beverage was PepsiCo's Mountain Dew, accounting for 4.5 percent of the market, followed by Cadbury Schweppes' Dr Pepper at 4 percent.
Indeed, according to the Beverage Marketing Corporation, Cadbury Schweppes was the sole major company to see growth in carbonated soft drink volume, with its 7UP, Dr Pepper and other soft drink brands experiencing growth of 1.3 percent in 2006.
After soft drinks, the second largest beverage category by volume - bottled water - enlarged by close to 10 percent in 2006. The two bottled water brands among the top ten liquid refreshment beverages stood at the bottom of the list in 2006, but are poised to move up in the rankings, said the report.
Fruit beverages were the third largest category in 2006, although overall sales declined 2.4 percent in the year. After sports drinks, which held fourth place in the beverage market, ready-to-drink teas came in fifth, experiencing a 26 percent volume growth.
Energy drinks, with growth of 49.1 percent, were the sixth largest category, followed by ready-to-drink coffee, which grew by 10.4 percent.
Overall, the market remained dominated by the big players. Pepsi led the list in 2006, recording nearly $9.6bn in estimated revenues for the year. Coca-Cola followed with $7bn, and Cadbury Schweppes' US beverage business generated $4.5bn in the year.